Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics.
Risk factors for the development of a post-transplant
UTI can be divided into pre-operative (host) factors, intra-operative factors and post-operative factors. Preoperative factors include female sex, diabetes mellitus and the presence of urological abnormalities.
The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
We aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode. Then we assessed if UTI resulted in declining allograft function at 2 years post-transplant.
We had very low rates of UTI or bacteremia caused by
ESBL-producing organisms and none of our patients died as a result of UTI. Nevertheless, there is a known association between mortality and bacteremia secondary to MDR gram negative infections in transplant recipients and MDR infections are expected to become more problematic in the future
In this study, UTIs acutely affected renal function during an episode, with renal function approaching baseline from 2 weeks post UTI. Importantly, UTIs did not impair overall renal function at 2 years post-transplant.
Many of the reported risk factors for UTIs in this population, such as gender and age, cannot be mitigated. Moreover, vigilance and monitoring for hyperglycaemia in the transplant population is important for cardiovascular benefits aside from hyperglycaemia being a predictor of increased UTI risk.
It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data, but the results are nevertheless indicative of important trends.
In conclusion, our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
Please summarise this article. # The aim:
*To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode.
Utilisation rates of TMP/SMX prophylaxis were also investigated.
# Introduction:
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%.
*The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics.
*Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases
Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurrent UTI.
*Risk factors for the development of a post-transplant
UTI can be divided into pre-operative factors, intra-operative factors and post-operative factors.
*The 2009 (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.
# Methods:
*This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital. Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were captured.
*Baseline demographics were collected for all adult patients (> 18 years old)
who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July
1st 2011 to July 1st 2016.
*The study included all adult patients returning to centre who had their post-transplant care with us for 2 years from their renal transplant date and within the above specified timeframe.
*The study excluded those patients returning to centre within the above timeframe but not completing their 2 years of post-transplant care with us, as well as those who received their transplant outside the specified timeframe.
# Results:
* Of these patients, 20 (27.8%) had at least one UTI.
* Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis.
* Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on
adjusted analysis.
* On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode,
which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance. (p = 0.076).
* Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment.
*Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
* The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
# The limitation of the study:
*Itts retrospective nature, small sample size and relatively limited follow-up.
*It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data. *UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
# Conclusion:
The results are valid for a similar closely monitored low immunosuppression transplant cohort and study findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
# The level of evidence is level 2
Summary Retrospective study – at the Royal Brisbane and Women’s Hospital, 72 renal transplant recipients with 5-year follow up are presented here. Patients’ charts, pathology records and dispensing histories were reviewed. All UTIs from 2 years post transplantation were noted. The prevalence, risk factors for post-transplant UTIs was identified; its effects on renal function during and after 2 years post-transplant was observed. In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis were also quantified. Results Out of 72 renal transplant patients – 55 were deceased donor, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants. Of these patients, 20 (27.8%) had at least one UTI episode. Old age, female sex, anatomic abnormality, hyper-glycemia, acute rejection episodes were the risk factors for developing UTI. Common organisms – Escherichia coli and Klebsiella pneumoniae accounted for 82% of UTI episodes. 70% of UTI cases required only single course of antibiotic treatment – either penicillin (49%) or cephalosporin (36%) was used in the majority of cases. Use of TMP/SMX for PCP prophylaxis did not reduce UTI rate – (90% of the cohort using this). There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI. Also, no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort noted. None of patients died as a result of UTI. UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI. Discussion The incidence of UTIs in a renal transplant was 27.8% Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared to removal at 4 weeks. There is association between mortality and bacteremia secondary to MDR Gram- negative infection. Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function. Limitations: A retrospective nature Small sample size All cases of UTI – asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included Level of evidence : Level 2 (retrospective observational study)
●(UTI) are the most common of infections after renal transplantation
• asymptomatic bacteriuria,
• acute simple cystitis (lower UTI),
• acute pyelonephritis (complicated UTI),
• and recurrent UTI
●The‘classical’ symptoms of UTI, are often absent in the renal transplant population
● UTI in a renal transplant recipient may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
●A urine dipstick test is routine practice allowing for the early detection of asymptomatic bacteriuria
● Gram-negative rods are the main pathogens
Escherichia coli is the most common uropathogen
Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species
● (MDR) gram negative bacteria, is most problematic in the Australasian region
MDR bacteria such as (ESBL) producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae
Risk factors for the development of a post-transplant UTI can be divided into
• pre-operative (host) factors,
• intra-operative factors
• and post-operative factors.
Postoperative factors
• acute allograft dysfunction and rejection
• as well as excessive immunosuppression as a result of rejection episodes
●The 2009 (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
A recent study of over 60,000 renal transplant recipients from 2000 to 2011 from the United States Renal Data System registry for infections in the first 12 months post-transplantation demonstrated that 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
We aimed to identify
the prevalence and risk factors for post-transplant UTIs
and assess UTIs’ effect on renal function during a UTI episode.
The declining allograft function at 2years post-transplant.
Methods
● A retrospective observational study was conducted at the (RBWH),
(>18 years old) who received a renal transplant and whose post-acute transplant follow-up was from July 1st 2011 to July 1st 2016.
●This study was approved by the Royal Brisbane and Women’s Hospital Human Research Ethics Committee
●72 patients in total
●Induction therapy consisted of either intravenous basiliximab or ATG and methylprednisolone, together with tacrolimus and mycophenolate.
Results
●There was no association with UTI for those that received thymoglobulin induction (p=0.20).
●the mean number of UTIs per person was 3.85.
● 33.8% of the UTI episodes were classified as a complicated pyelonephritis).
● ESBL-producing organism in 3.9% of urine cultures
●TMP/SMX prophylaxis at a dose of 400/80mg/day was almost universal
●there was no significant change in serum creatinine and (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
Or between those with a complicated UTI/pyelonephritis versus those with a simple UTI (p=0.331).
Discussion
●Our study highlights the incidence of UTIs in a renal transplant population with 27.8%
Female gender and age were the only risk factors that reached statistical significance.
●Many studies have revealed an association between stent usage and higher rates of UTI
● trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs.
●UTIs did not impair overall renal function at 2 years post-transplant.
● Some cohort studies have demonstrated higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%.
●Furthermore, in other studies severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
Why The time-point of 2 years post-transplant was chosen ?
●●Firstly, increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial three to 6 months.
●●Secondly, 2 years represented a reliable and accessible dataset.
● What is not clear from this study is the manner in which monitoring and surveillance of UTIs should occur
●What is also not clear from this study is the effectiveness of prophylactic antibiotics in those patients with frequent or recurrent UTIs
●Our study highlights that UTIs are very common.
● Risk factors were in line with other published studies with female gender, older age and hyperglycaemia conferring risk.
●UTIs did not affect renal function at 2 years post-transplant, and despite 93% of our patients taking TMX-SMX prophylaxis, the trimethoprim component seemed not to confer protection against UTIs.
●ESBL organisms causing UTIs were relatively uncommon at 3.8%.
The limitations in this study design,
○ retrospective nature,
○ small sample size
○ relatively limited followup
●It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data
● an allencompassing UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis
● the evidence does not support treating asymptomatic bacteriuria, however many clinicians would treat if it is accompanied by an unexplained rise in serum creatinine.
In conclusion,
our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
This article is surrounding urinary tract infections in renal transplant recipients. UTIs are one of the most common infections post transplant. UTIs can cause increased morbidity and mortality in the transplant population and has been widely cited as a fatal infection if not treated. In addition, UTI has the potential to cause acute dysfunction of the allograft and also increase hospitalization rates in transplant recipients. Long term survival of graft may be impaired, although further studies are needed to confirm this.
Discussion
This study analyzed the prevalence, risk factors, and effect on renal function that UTIs have post transplant.
Risk factors includes female gender, increasing age and usage of stent. However, early removal of tent within 1 week has found to be associated with lower incidence of UTIs in this patient sector. Previous history of UTI has not been found to increase risk of post transplant UTI.
TMP may not be highly effective as prophylaxis against UTI since a large number of patients develop infection despite prophylaxis. In addition, TMP can cause a reversible increase in serum creatinine due to inhibition of the tubular secretion of creatinine.
The study found that while UTI had an acute effect on graft function, it did not adversely impact graft function in the near future. Early detection and aggressive treatment may be a contributing factor to this outcome. This can also protect graft function at 2 years post transplant, which is the most common period for complicated and possibly fatal UTI.
This study does not encourage treatment of asymptomatic bacteriuria, however, if this is accompanied with unexplained rise in serum creatinine, then treatment can be considered.
Conclusion
Aggressive treatment, early detection and low immunosuppression play a key role in treating UTI and protecting allograft function in the long and short term.
Summary
This was a retrospective analysis of 72 kidney transplant patients treated at the Royal Brisbane and Women’s Hospital during a 5-year period.
To determine the prevalence and risk factors for post-transplant UTIs and to evaluate the impact of UTIs on renal function both during and after 2 years post-transplant by UTI episode, patient charts, pathology records, and dispensing histories were reviewed. All UTIs occurring from 2 years after transplantation were reported.
Additionally, the kind of antibacterial medicine used for each episode of a UTI, as well as the usage of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis, were measured.
Result
72 individuals underwent kidney transplants; of them, 55 were from deceased donors, 7 from live relatives, and 10 underwent combined kidney and pancreas transplants.
20 (27.8%) of these individuals had at least one UTI.
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
82% of UTI episodes were caused by common microorganisms (Klebsiella pneumoniae and Escherichia coli).
Between individuals with and without a UTI, there was no discernible difference in serum creatinine and estimated glomerular rate (eGFR) from baseline to two years after the transplant.
Additionally, there was no statistically significant difference between those who had a difficult UTI/pyelonephritis and those who had a simple UTI or the remainder of the group in the change in serum creatinine from baseline to 2 years after the transplant.
None of the individuals experienced fatal UTI.
Renal function was impacted by UTIs during an episode, returning to baseline 2 weeks after the UTI.
Discussion
Discussion
In a kidney transplant, the prevalence of UTIs was 27.8%.
In comparison to removal at 4 weeks, early ureteric stent removal at 1 week was linked to a reduced risk of UTIs.
Bacteremia brought on by MDR gram negative infection is associated with death.
Long-term renal function may be negatively impacted by severe UTIs and urosepsis.
Limitations:
an ahistorical nature
a modest sample size
Cystitis, transplant pyelonephritis, and all asymptomatic bacteriuric UTI patients were included.
it is retrospective observational study level 2
This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital.
Patient charts, pathology records and dispensing histories were reviewed and all UTIs from 2 years post transplantation were noted to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during and after 2 years post-transplant by UTI episode.
In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
Results
Out of 72 renal transplant patients, 55 were deceased donor, 7 were living related kidney transplants and 10 were simultaneous kidney pancreas transplants.
Of these patients, 20 (27.8%) had at least one UTI
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes.
70% of UTI cases require only a single course of antibiotic treatment.
Antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI.
There was also no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort.
None of patients died as a result of UTI.
UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI.
Discussion
The incidence of UTIs in a renal transplant was 27.8%
Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with removal at 4 weeks.
There is association between mortality and bacteremia secondary to MDR gram negative infection.
Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function.
Limitations:
A retrospective nature
Small sample size
All cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included
Level of evidence for retrospective observational study is Level: 2
Urinary tract infections (UTIs) are a common complication after renal transplantation, with estimated incidences varying widely due to inconsistencies in definitions and diagnostic criteria across studies. The American Society of Transplantation Infectious Diseases Community of Practice has attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI. The symptoms of UTI in renal transplant recipients may be atypical due to immunosuppression and surgical denervation of the transplanted kidney and ureters. Risk factors for post-transplant UTI include pre-operative factors, intra-operative factors, and post-operative factors. UTIs in this population can result in increased morbidity and hospitalization rates, acute allograft dysfunction, and even an increased risk of death. The prevalence and risk factors for post-transplant UTIs were investigated in a retrospective observational study conducted at a quaternary level hospital in Brisbane, Australia.
The study aimed to assess the effect of UTIs on renal function during a UTI episode and to determine if UTI resulted in declining allograft function at 2 years post-transplant. The study also collected data on causative organisms and antibiotics used. Statistical analysis was performed to identify associations between variables.
RESULTS In a 5-year study of 72 first-time renal transplant patients, 27.8% experienced at least one UTI, with a mean of 3.85 UTIs per person in the UTI sub-group. Univariate analysis showed older age, female gender, hyperglycemia, and acute rejection episodes as risk factors for UTI, but only female gender and age remained statistically significant in adjusted analysis. UTI episodes led to a significant increase in serum creatinine levels, but there was no significant change in serum creatinine or eGFR up to 2 years post-transplant between patients with or without UTIs. Complicated and simple UTIs did not differ significantly in their effect on serum creatinine levels.
DISCUSSION
This study examined UTIs in renal transplant patients, finding a 27.8% incidence rate, with female gender and age as statistically significant risk factors. Surprisingly, pre-existing history of UTI or urogenital abnormality were not risk factors. The study observed low rates of UTI or bacteremia caused by ESBL-producing organisms and no UTI-related deaths. Trimethoprim usage for Pneumocystis prophylaxis did not seem to protect against UTIs, raising questions about its effectiveness in UTI prophylaxis for kidney transplant patients. UTIs acutely affected renal function, but did not impair overall renal function at 2 years post-transplant. The study’s limitations include its retrospective nature, small sample size, and relatively limited follow-up. Despite these limitations, the results offer an interesting perspective on UTI risk factors, treatment, and the concept of antibiotic prophylaxis for UTIs in renal transplant patients. The findings are valid for similar closely monitored low immunosuppression transplant cohorts.
UTI- commonest post renal transplant infections ranging between 10 and 98%. The cause of discrepancy is attributed mainly to the availability of the diagnostic tools and prophylactic measures.
After long practice finally the last updates by the AST Infectious Diseases Community of Practice 2019 guidelines managed to establish clear definitions for all UTI syndromes particularly: asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis and recurrent UTI.
Common ‘classical’ symptoms of UTI in the form of urinary frequency, dysuria, urgency, or suprapubic pain, mostly don’t exist owing to the combination of IS and surgical denervation of the transplanted kidney and ureters. Thus, the presentation may be vague as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine, highlighting the routine outpatient dipstick testing is mandatory.
The most common organism encountered is Escherichia coli followed by other common enteric organisms as Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.
Risk factors
female sex
diabetes mellitus
presence of urological abnormalities
use of ureteric stents
prolonged indwelling bladder catheterisation.
the exposure to acute allograft dysfunction and rejection necessitating the excessive use of immunosuppression.
UTIs in this population poses the patients to the risk of increased morbidity, hospitalisation rates besides acute allograft dysfunction.
The question then is does it affect long-term allograft function or reduce allograft or patient survival.
A study conducted by the USRDS registry for infections for more than 60,000 renal transplant recipients from 2000 to 2011 in the first year post renal transplantation concluded that 32% of patients had a UTI in the first year which was associated with a 41% increased relative risk of death.
This retrospective observational study performed at the Royal Brisbane and Women’s Hospital (RBWH) for 2 years duration post renal transplantation.
The study population involved all adult renal transplant recipients (> 18 years old even simultaneous kidney-pancreas transplantation) as well as those having their post-acute transplant follow-up at RBWH from July 1st 2011 to July 1st 2016.
UTI is defined by the existence of bacteriuria proved by laboratory reports and receipt of one or more courses of antibiotics. Importantly, three consecutive sera creatinine were needed; ‘Pre-UTI’ was within 3 months before the episode, the ‘UTI episode’ within 2 weeks of recorded bacteriuria and ‘post UTI’ by 15 days to 3 months post UTI.
All UTI episodes were included from 1 month post renal transplantation up to 2 years. Severity was classified by the presence of simple cystitis or by complicated UTI/pyelonephritis requiring hospital admission for parenteral antibiotic therapy.
A total number of 72 patients (55 deceased donor transplants, 7 LRRT and 10 simultaneous kidney pancreas transplants) were first renal transplant.
There were no association between the occurrence of UTI and induction therapy even those who received thymoglobulin induction which were only 3 patients (p = 0.20).
The mean age at transplantation was 45.5 years (median: 47, range: 17–71). All patients removed catheter 3–5 days post transplantation. Also, ureteric stents were removed 4–6 weeks post operatively.
In this study, 20 patients had at least one UTI over the study period with incidence rate for a UTI was 27.8%. The mean number of UTIs per person among all patients was 3.85.
About 55% of the patients (11/20) in the UTI subgroup had at least one episode of complicated UTI/pyelonephritis.
The other group 45% (9/20) had at least one simple UTI episode. Total of 33.8% of the UTI episodes were considered complicated UTI/pyelonephritis (26/77).
It was found that only 8% (6/77) of blood cultures obtained at time of a UTI episode were positive.
ESBL-producing organism in 3.9% of urine cultures (3/77) was the most common. It had the feature of response to penicillin, gentamicin and carabepenem.
The study also confirmed that older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) are still considerable risk factors for developing UTI.
However, HLA mismatches and strong pre-existing history of UTIs were not found to be risk factors anymore.
Each UTI episode was associated with a mean increase in serum creatinine of 21 micromol/L (14.4%, SEM 5.20) and statistically significant (p = 0.027).
While after resolution of the UTI, the estimated mean reduction was 16 micromol/L (9.1%, SEM 6.23) reduction in serum creatinine with statistical significance (p = 0.076).
There was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between both groups with complicated UTI/pyelonephritis and simple UTI (p = 0.331) or even the rest of the whole cohort (p = 0.814).
The high incidence of post renal transplant UTI about 27.8% was like other studies. Concerning the known risk factors for developing a UTI as other studies only female gender and age were the only significant risk factors while pre-existing history of UTI or urogenital abnormality are no more considered risk factors.
In 2016, a study elaborated that early removal of ureteric stents at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks while our study found that they were not linked at all.
The study proved low rates of ESBL-producing organisms UTI or bacteraemia besides no deaths were encountered due to UTI.
The use of trimethoprim for Pneumocystis prophylaxis was not associated with more protection against UTIs in our patients even when being used by 93% of patients at doses considered prophylactic for UTIs.
Among all groups, no significant difference in baseline serum creatinine levels was demonstrated.
Limitations were mainly being retrospective with small sample size and relatively limited follow up duration. In order to assess the patients’ long-term allograft function 2-year study duration is definitely not satisfactory.
Strengths were the wide application of the definition of UTI in all cases.
V. Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Summarise this article
Background
– UTIs are the most common infections post kidney transplant, estimated incidence is 10-98%
– UTIs are associated with increased morbidity, hospitalization rates and acute graft dysfunction
– UTIs impair graft and patient survival
– definitions/ classification of ASB and UTI in KTRs:
· asymptomatic bacteriuria (ASB): no urinary or systemic symptoms of infection
· acute simple cystitis (lower UTI): dysuria, urgency, frequency or suprapubic pain but no systemic symptoms, no ureteral stent, nephrostomy tubes, chronic urinary catheter
· acute pyelonephritis (complicated UTI): fever, chills, malaise, hemodynamic instability, leukocytosis (with no other apparent etiology), flank/ graft pain, bacteremia with same organism as in urine, dysuria, urgency, frequency, suprapubic pain may or may not be present
· recurrent UTI: ≥3 UTIs in prior 12-month period
– the classical symptoms of UTI i.e., frequency, dysuria, urgency, suprapubic pain, are often absent in KTRs due to immunosuppression and surgical denervation of the transplanted kidney and ureters
– therefore, UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine
– routine urine dipstick test allows for early detection of ASB in KTRs
– gram negative rods are the main cause of UTIs in both the transplant and the non-transplant population i.e., E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterococci
– there is a notable increase in pathogenic MDR gram-negative bacteria e.g., ESBL producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae which require use of the much older antibiotics which could be nephrotoxic
– Risk factors for development of posttransplant UTI:
· Pre-operative (host) factors: – female sex, diabetes, presence of urological abnormalities
· Intra-operative factors: – DDKT, use of ureteric stents, prolonged indwelling urethral catheter
· Post-operative factors: – acute graft dysfunction, rejection, excessive immunosuppression secondary to rejection episodes
– KDIGO 2019 recommends TMP-SMX for PCP prophylaxis for at least 6 months posttransplant
– however, there are studies showing a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis
– UTIs in KTRs are associated with increased morbidity and hospitalization rates, acute graft dysfunction
– since most studies are retrospective, it is not clear whether UTIs impair long-term graft function or reduce graft or patient survival
Methods
– retrospective observational study, 72 KTRs, 5-year period
– patient’s charts, pathology records and antibiotic dispensing records were reviewed
– all UTIs 2 years posttransplant were captured
– Aim:
· to determine the prevalence and risk factors for posttransplant UTIs
· to assess the effect of UTIs on kidney function during a UTI episode
· to assess if UTIs result in declining graft function at 2 years posttransplant
· to document the causative agent, class of antibiotics used for each UTI episode, number of different antibiotics used per episode, utilization rates of TMP-SMX prophylaxis
– UTI was defined as presence of bacteriuria on laboratory reports and use of one or more courses of antibiotics
– this definition therefore included all cases of acute simple cystitis, transplant pyelonephritis and ASB if treated with antibiotics
– ASB was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary to use antibiotics three consecutive sera creatinine were reviewed i.e., “pre-UTI” (within 3 months prior to the UTI episode), “UTI episode” (within 2 weeks of a recorded bacteriuria) and “post-UTI” (15 days to 3 months post a UTI episode)
– patients were stratified into presence or absence of at least one UTI episode, those with a UTI episode were subclassified into uncomplicated (simple cystitis) vs complicated UTI (pyelonephritis, systemic symptoms requiring hospital admission for parenteral antibiotics)
Results
– 72 patients were reviewed, 55 DDKT, 7 LDKT, 10 simultaneous kidney and pancreas transplants
– induction therapy: Basiliximab or ATG and methylprednisolone, together with tacrolimus and mycophenolate
– there was no association between ATG use and UTIs
– maintenance therapy: tacrolimus, mycophenolate, prednisone
– tacrolimus trough level target: 5ng/ml for intermediate immunologic risk patients and 6-7ng/mL for those with a high immunologic risk
– mean age at transplantation was 45.5 years
– indwelling urine catheter was removed 3-5 days posttransplant
– ureteric stent was routinely removed 4-6 weeks posttransplant unless patients developed early UTI in which case it would be removed earlier
– 27.8% (20 patients) had at least one UTI
– in the UTI sub-group, 77 UTI episodes were analysed, mean number of UTI episodes per person was 3.85, 55% of the patients had at least one episode of complicated UTI while 45% had simple UTI, 33% of the UTI episodes were complicated UTI/ pyelonephritis, ESBL-producing organism (E. coli) was isolated in 3.9% of the urine cultures
– E. coli and Klebsiella pneumonia accounted for 82% of the UTI episodes
– 70% of the UTI cases responded to a single course of antibiotics
– antibiotics commonly used were either a penicillin (49%) or cephalosporin (36%)
– 93% of the patients were on TMP-SMX prophylaxis
– use of TMP-SMX prophylaxis for PCP prophylaxis did not influence the rate of UTI
– risk factors for developing UTI: older age, female sex, hyperglycemia, acute rejection episodes
– there was an increase in serum creatinine (21micromol/L) during a UTI episode with a notable decline in serum creatinine (16micromol/L) after the UTI episode
– there was no significant difference in serum creatinine and eGFR from baseline to 2 years posttransplant
Discussion
– UTI is the most common infection following kidney transplant
– risk factors for UTI: female sex, age, hyperglycemia
– there is an association between stent usage and higher rates of UTI
– there is a relationship between mortality and bacteremia secondary to MDR gram negative infections in KTRs
– TMP-SMX use for PCP prophylaxis does not confer protection against UTIs
– UTIs acutely affects kidney function but does not impair overall kidney function at 2 years posttransplant
– ESBL organisms causing UTI were uncommon
Study limitations
– retrospective study
– small sample size
– limited follow up
Conclusion
– there was no significant change in serum creatinine and eGFR from baseline to 2 years posttransplant between those with or without a UTI episode
Level of evidence provided by this article?
– Level II
● Urinary tract infections (UTI) are the most common of infections after renal transplantation with incidence 10 – 98%
● Definitions UTI syndromes including:
☆ Asymptomatic bacteriuria: No urinary or systemic symptoms of infection
☆ Acute simple cystitis (lower UTI): Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/
nephrostomy tube/chronic urinary catheter
☆ Acute pyelonephritis (complicated UTI)
Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency, frequency, suprapubic pain may or may not be present
☆ Recurrent UTI
≥3 UTIs in prior 12 month period
● The ‘classical’ symptoms of UTI are often absent in the renal transplant
● UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
● Escherichia coli is the most common uropathogen
● Risk factors for UTI divided into :
☆ pre-operative (host) factors:
* Female sex
* Diabetes mellitus
* Presence of urological abnormalities.
☆ Intra-operative factors :
* A deceased donor
* Use of ureteric stents
* Prolonged indwelling bladder catheterisation
☆ Post-operative factors :
* Acute allograft dysfunction
* Rejection
* Excessive immunosuppression as a result of rejection episodes
● It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival
● 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
◇ Methods
☆ A retrospective observational study
☆ All adult patients (> 18 years old) who received a renal transplant
☆ from July 1st 2011 to July 1st 2016.
☆ UTI is defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
☆ This included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
☆ Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
☆ To estimate renal function three sera creatinine were reviewed.
▪︎Pre-UTI: 3 months prior to an episode,
▪︎UTI episode: within 2 W of bacteriuria
▪︎post UTI: 15 D to 3 M post a UTI episode.
☆ Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
☆ All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
◇ Discussion
● The incidence of UTIs in a renal transplant was 27.8%
● Risk factors for developing a UTI, Female gender and age were the only risk factors reached statistical significance
● A pre-existing history of UTI or urogenital abnormality were not found to be a risk factors
● Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with stent removal at 4 weeks
● Very low rates of UTI or bacteremia caused by ESBL-producing organisms
● None of patients died as a result of UTI.
● There is association between mortality and bacteremia secondary to MDR gram
● Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in patients
● Trimethoprim causes a reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine
● UTIs affected renal function during an episode, with renal function approaching baseline 2 weeks post UTI.
● UTIs did not impair overall renal function at 2 years post-transplant.
● Higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%
● Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
● Hyperglycaemia being a predictor of increased UTI risk.
● ESBL organisms causing UTIs were relatively uncommon at 3.8%.
● Limitations:
☆ A retrospective nature
☆ Small sample size
☆ Relatively limited followup.
☆ Study encompassing all cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis Although evidence does not support treating asymptomatic bacteriuria
☆ The manner in which monitoring and surveillance of UTIs should occur is not clear
☆ The effectiveness of prophylactic antibiotics in those patients is not clear
● Level : 2
Introduction:
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilization rates of prophylactic antibiotics.
the diagnosis of UTI among renal transplant recipients has been fraught by such inconsistencies up until now.
Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant populations . Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species. Risk factors for posttransplant UTI:
1. Preoperative: female sex, diabetes mellitus and the presence of urological abnormalities.
2. Intraoperative: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization
3. Postoperative. acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes.
UTIs in this population are serious with increased morbidity and hospitalization rates, as well as acute allograft dysfunction Methods:
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period. Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July 1st 2011 to July 1st 2016.
For the purpose of this study, we defined UTI as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics. Results:
Over a 5 year period, 72 patients were reviewed posttransplant. over this time
there were 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants. All 72 patients include in this study had received their first renal transplant.
Induction therapy consisted of either intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate. 95.7% received intravenous basiliximab as their induction agent, with only 3 patients receiving thymoglobulin induction. There was no association with UTI for those that received thymoglobulin induction (p = 0.20). Patients were then maintained on a combination of tacrolimus, mycophenolate and prednisolone throughout the post-transplant period. Tacrolimus was dosed to target a trough of 5 ng/ml for patients with average immunological risk and 6–7 ng/ml for those with high immunological risk. Prednisolone was tapered to 6–7 mg / day wherever possible. Mycophenolate mofetil/sodium remained at 1 g twice daily/720 mg twice daily unless there was leucopenia, intolerable gastrointestinal side effects, a high risk of infections or a new malignancy, in which case it was reduced. Conclusion:
Our study highlights the incidence of UTIs in a renal transplant population with 27.8% of this cohort experiencing a UTI. Similar rates have been demonstrated in other studies and support the notion that UTI remains the most common infection after renal transplantation.
The study identified risk factors for developing a UTI.
our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs. Level of evidence is II
Aim:
Identify the prevalence and risk factors and more understanding about post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode.
Retrospective study at quaternary hosital.
Inclusion criteria: Adults >18 yrs who received renal or renal pancreas transplant who followed up at RBWH;July 1st 2011 to July 1st 2016 for two years post Tx.
Results;
Total population 72, 27.8% had at least one UTI.
Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis. Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on adjusted analysis. On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode, which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance. (p = 0.076).
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment. Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
Limitations Retrospective study, single centre, small number, short FU
This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital.
Patient charts, pathology records and dispensing histories were reviewed and all UTIs from 2 years post transplantation were noted to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during and after 2 years post-transplant by UTI episode.
In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
Results Out of 72 renal transplant patients, 55 were deceased donor, 7 were living related kidney transplants and 10 were simultaneous kidney pancreas transplants. Of these patients, 20 (27.8%) had at least one UTI
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis. Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes. 70% of UTI cases require only a single course of antibiotic treatment.
Antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI.
There was also no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort.
None of patients died as a result of UTI.
UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI.
Discussion The incidence of UTIs in a renal transplant was 27.8%
Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with removal at 4 weeks.
There is association between mortality and bacteremia secondary to MDR gram negative infection.
Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function. Limitations: A retrospective nature Small sample size All cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included
Level of evidence for retrospective observational study is Level: 2
summary
· This study examined the prevalence and risk factors for post-transplant UTIs in 72 renal transplant patients at a quaternary care centre in Australia.
· Results showed that 20 (27.8%) had at least one UTI, with older age, female gender, hyperglycaemia, and acute rejection episodes being risk factors for developing a UTI.
· On average, there was a 14.4% increase in serum creatinine during a UTI episode, which was statistically significant.
· Urinary tract infections (UTI) are the most common of infections after renal transplantation, with an estimated incidence between 10 and 98%.
· However, the diagnosis of UTI among renal transplant recipients has been fraught by inconsistent definitions and diagnostic criteria.
· Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases have attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI.
· The ‘classical’ symptoms of UTI are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters.
· UTI can be divided into pre-operative (host) factors, intra-operative factors and post-operative factors, with pre-operative factors such as female sex, diabetes mellitus and urological abnormalities.
· The 2009 (KDIGO) guidelines recommend TMP/SMX for pre-prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.
· UTIs in this population are serious with increased morbidity and hospitalisation rates, as well as acute allograft dysfunction.
· in this study, UTI was defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
· All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
· Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
· Gender, type of transplant, type of kidney-pancreas (KP), pre-existing history of UTIs, pre-existing urinary tract abnormality, acute rejection episodes, hyperglycaemia, post-transplant diabetes, CMV viraemia, and TMP/SMX use were also examined.
· The ureteric stent was routinely removed 3-5 days after transplantation.
· 55% of the patients had at least one episode of complicated UTI/pyelonephritis, with 45% having at least one simple UTI episode.
· isolated an ESBL-producing organism in 3.9% of urine cultures and all three isolates were sensitive to penicillin, gentamicin and carabepenem initially, but one of the isolates has since become carbapenem-resistant.
· TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal in this cohort, with 85.7% of these patients using nitrofurantoin.
· Overall, there was no significant change in serum creatinine and (eGFR) from baseline out to 2 years post-transplant.
· There was no significant difference in baseline serum creatinine levels between the two subgroups as the vast majority of patients were on TMP-SMX prophylaxis.
· The time-point of 2 years was chosen as a reference point for a number of reasons, including the increased risk of UTIs in the initial 12 months and the high levels of immunosuppression employed in this period. · level of evidence :
level 3 , a retrospective cohort study
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Study objective:
1) Prevalence of UTI
2) Risk factors for post-transplant UTI
3) The effects of UTI on renal function (during the episode) and 2 years post-transplant
Study design
Retrospective cohort study
Population
72 renal transplant recipients from a single centre
Results
1) Prevalence: 20/72 (27.8%) had at least one UTI
2) Risk factors: Older age, female, hyperglycaemia, acute rejection
3) Increased in serum creatinine during the episodes in 14.4% but no difference in 2 years follow up
4) Other analysis
Introduction:
Urinary tract infections (UTI) is the most common post renal transplant infections 10 and 98% according to different studies .
the American Society of Transplantation Infectious Diseases Community of Practice 2019 guidelines managed attempt to establish clear definitions for all UTI syndromes particularly:
– asymptomatic bacteriuria,
– acute simple cystitis (lower UTI),
– acute pyelonephritis (complicated UTI),
– recurrent UTI.
Classification of asymptomatic bacteriuria and UTI in renal transplant recipients [3]
Classification Description
Asymptomatic bacteriuria No urinary or systemic symptoms of infection
Acute simple cystitis Dysuria, urinary urgency/frequency, or suprapubic pain; but no
systemic symptoms and no ureteral stent/ nephrostomy
tube/chronic urinary catheter.
Acute pyelonephritis/ Fever, chills, malaise, haemodynamic instability, or leukocytosis
complicated UTI (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency,
frequency, suprapubic pain may or may not be present
Recurrent UTI ≥3 UTIs in prior 12 month period
Transplant patient UTI may not present with classical known signs and symptoms of frequency of micturition, dysuria, urgency or suprapubic pain, because of immunosuppression and surgical denervation of the transplanted kidney and ureters.
The patient may present with non-specific symptoms of new febrile illness, urosepsis or impaired graft function which raise the importance of routine outpatient dipstick testing.
The most common organism :
1- encountered is Escherichia coli ( most common) .
2- Klebsiella pneumonia.
3- Pseudomonas aeruginosa .
4- and Enterococci species.
Risk factors include :
1- female sex.
2- diabetes mellitus.
3- urological abnormalities.
4- use of ureteric stents and prolonged indwelling bladder catheterisation.
5- acute allograft dysfunction and rejection treated with heavy immunosuppression.
The presence of UTI increase the rate of morbidity, hospitalisation and acute allograft dysfunction.
According to large USA study this UTI is associated with41% increased relative risk of death.
Result :
72 patients were recruited- 55DCD, 7 LKD and 10 simultaneous kidney-pancreas transplant.
The induction therapy (basiliximab or ATG with methylprednisolone). With Maintenance therapy was triple therapy. All patients had an indwelling catheter . All patients had a ureteric stent.
20 out of 72 had a UTI with incidence rate of 27.8%.
11 out of 20 (58%) had a complicated UTI.
ESBL producing organism was isolated in 3.9%.
66out of 72 were on TMP/SMX prophylaxis.
Discussion:
UTI is the most common infection post transplantation.
Regarding the risk factors it revealed that
female gender and age are the only statistically significant risk factors for UTI .
data from one study report that early (1wk) stent removal is linked to lower UTI.
ESBL rate was low in this study. Trimethoprim used PJP is not protective against UTIs .
Acute UTIs may affect graft function in short term, but UTI has no effect on long term graft function. With each UTI attack there is an increase in serum creatinine level.
This Reported by Other studies demonstrating that severe UTIs and urosepsis producing negative impact on long-term graft function.
This study shows ineffectiveness of trimethoprim prophylaxis to prevent UTI.
The effective prophylactic program for UTI is needed to be determined .
Limitations;
– retrospective .
– small sample size .
– short follow up period .
Strength ;
– Involving all UTI definition
– involving asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
Q2- What is the level of evidence provided by this article?
Level of evidence 2
This study by OLENSKI and colleagues aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
Additionally, the causative organism, the class of antibacterial drug employed for each UTI episode and utilisation rates of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
BACKGROUND
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%.
Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant popula- tions [5]. Escherichia coli is the most common uropatho- gen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and En- terococci species. Furthermore, on a global scale there are increasing numbers of pathogenic multi-drug resist- ant (MDR) gram negative bacteria.
RISK FACTORS
Risk factors for the development of a post-transplant UTI can be divided into pre-operative (host) factors intra-operative factors and post-operative factors.
Pre- operative factors include female sex, diabetes mellitus and the presence of urological abnormalities.
Intra- operative factors of note include kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterisation.
Post- operative factors of note include acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes
PROPHYLAXIS
The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
METHODS
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period. Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July 1st 2011 to July 1st 2016.
They included in this study all adult patients returning to their centre who had their post-transplant care with for 2 years from their renal transplant date and within the above specified time- frame.
They excluded those patients who did not complete 2 years of post transplant care.
Patients were stratified into two groups according to the presence or absence of at least one UTI episode. All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant. Theyfurther stratified the UTI sub-cohort for severity into those with simple cystitis versus those with complicated UTI/pyelo- nephritis.
RESULTS
Over a 5 year period, 72 patients were reviewed post- transplant.
There were 55 deceased donor transplants,
7 living related kidney transplants and
10 simultaneous kidney- pancreas transplants.
All 72 patients include in this study had received their first renal transplant.
20 patients experienced at least one UTI over the study period and the incidence rate for a UTI was 27.8% across the whole cohort.
Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis.
Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on adjusted analysis.
On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode, which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance.
(p = 0.076).
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment. Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
CONCLUSION
There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those with and without a UTI.
Introduction
Urinry tract infection (UTI) are the most common of infections after renal transplataion with an estimated incidence between 10 and 98%.
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics .
The diagnosis of UTI among renal transplant recipients has been fraught by such inconsistencies up until now.
Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria , acute simple cystitis, acute pyelonephritis, and recurrent UTI.].
Objectives
We aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs ’ effect on renal function during a UTI episode.
We aimed to quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode
Methods
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period.
Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant and whose post-acute transplant follow-up was provided at RBWH from July.
For the purpose of this study, we defined UTI as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics
This allencompassing definition of UTI included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics Results
Our centre receives transplant patients from other transplanting centres and over this time-frame there were 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidneypancreas transplants.
All 72 patients include in this study had received their first renal transplant.
Induction therapy consisted of either intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate.
69) received intravenous basiliximab as their induction agent, with only 3 patients receiving thymoglobulin induction.
There was no association with UTI for those that received thymoglobulin induction (p = 0.20).
Patients were maintained on a combination of tacrolimus, mycophenolate and prednisolone throughout the post-transplant period.
Tacrolimus was dosed to target a trough of 5 ng/ml for patients with average immunological risk and 6–7 ng/ml for those with high immunological risk.
Mycophenolate mofetil/sodium remained at 1 g twice daily/720 mg twice daily unless there was leucopenia, intolerable gastrointestinal sideeffects, a high risk of infections or a new malignancy, in which case it was reduced Conclusion
Our study highlights the incidence of UTIs in a renal transplant population with 27.8% of this cohort experiencing a UTI .
Similar rates have been demonstrated in other studies and support the notion that UTI remains the most common infection after renal transplantation
This study is informative about UTIs in a carefully followed low immunosuppression transplant population and our observations are valid only for a similar population.
Female gender and age were the only risk factors that reached statistical significance on the adjusted analysis and surprisingly, a pre-existing history of UTI or urogenital abnormality were not found to be a risk factors on the unadjusted analysis.
Many studies have revealed an association between stent usage and higher rates of UTI.
A 2016 study demonstrated that early ureteric stent removal at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks. Level of evidence is 2
Introduction:
-Urinary tract infections (UTI) are the most common of infections after renal transplantation.
-The consequences of UTIs in this population are serious, with increased morbidity and hospitalisation rates as well as acute allograft dysfunction.
-UTIs may impair overall graft and patient survival.
-Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumonia , Pseudomonas aeruginosa , and Enterococci species. Risk Factors;
-Pre-operative (host) factors;
Include female sex, diabetes mellitus and the presence of urological abnormalities.
-Intra-operative factors;
Include kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization.
-Post-operative factors;
Include acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episode. Aim;
-Identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
-Additionally, the causative organism, the class of antibacterial drug employed for each UTI episode and utilisation rates of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified. Methodology:
-This was a retrospective study of 72 renal transplant patients over a 5-year period from (July 1st 2011 to July 1st 2016); who were managed at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
-Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were captured. Results:
-There were 72 renal transplant patients (had received their first renal transplant): 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants.
-Of these patients, 20 (27.8%) had at least one UTI; Older age , female gender , hyperglycaemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
-Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment.
-Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
-The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
-There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
-There was also no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI.
-There was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus the rest of the whole cohort. Discussion;
-Interestingly, a 2016 study demonstrated that early ureteric stent removal at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks.
-The time-point of 2 years post-transplant was chosen as a reference point for a number of reasons.
*Firstly, there is a well documented increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial three to 6 months, due to the surgical procedure itself and high levels of immunosuppression employed in this period.
*Secondly, from a pragmatic perspective, 2 years represented a reliable and accessible dataset in terms of dispensing and medical record accuracy. Limitations;
-Its retrospective nature, small sample size and relatively limited follow-up.
-It is difficult to judge on patients’ long-term allograft function using 2 year post-transplant data.
-UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
-Although evidence does not support treating asymptomatic bacteriuria in its own right, however many clinicians would treat if it is accompanied by an unexplained rise in serum creatinine. Conclusions;
-There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those patients with and without a UTI.
-This is a retrospective observational study, with (LOE II)
● Urinary tract infections (UTI) are the most common of infections after renal transplantation with incidence 10 – 98%
● Definitions UTI syndromes including:
☆ Asymptomatic bacteriuria: No urinary or systemic symptoms of infection
☆ Acute simple cystitis (lower UTI): Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/
nephrostomy tube/chronic urinary catheter
☆ Acute pyelonephritis (complicated UTI)
Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency, frequency, suprapubic pain may or may not be present
☆ Recurrent UTI
≥3 UTIs in prior 12 month period
● The ‘classical’ symptoms of UTI are often absent in the renal transplant
● UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
● Escherichia coli is the most common uropathogen
● Risk factors for UTI divided into :
☆ pre-operative (host) factors:
* Female sex
* Diabetes mellitus
* Presence of urological abnormalities.
☆ Intra-operative factors :
* A deceased donor
* Use of ureteric stents
* Prolonged indwelling bladder catheterisation
☆ Post-operative factors :
* Acute allograft dysfunction
* Rejection
* Excessive immunosuppression as a result of rejection episodes
● It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival
● 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
◇ Methods
☆ A retrospective observational study
☆ All adult patients (> 18 years old) who received a renal transplant
☆ from July 1st 2011 to July 1st 2016.
☆ UTI is defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
☆ This included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
☆ Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
☆ To estimate renal function three sera creatinine were reviewed.
▪︎Pre-UTI: 3 months prior to an episode,
▪︎UTI episode: within 2 W of bacteriuria
▪︎post UTI: 15 D to 3 M post a UTI episode.
☆ Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
☆ All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
◇ Discussion
● The incidence of UTIs in a renal transplant was 27.8%
● Risk factors for developing a UTI, Female gender and age were the only risk factors reached statistical significance
● A pre-existing history of UTI or urogenital abnormality were not found to be a risk factors
● Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with stent removal at 4 weeks
● Very low rates of UTI or bacteremia caused by ESBL-producing organisms
● None of patients died as a result of UTI.
● There is association between mortality and bacteremia secondary to MDR gram
● Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in patients
● Trimethoprim causes a reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine
● UTIs affected renal function during an episode, with renal function approaching baseline 2 weeks post UTI.
● UTIs did not impair overall renal function at 2 years post-transplant.
● Higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%
● Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
● Hyperglycaemia being a predictor of increased UTI risk.
● ESBL organisms causing UTIs were relatively uncommon at 3.8%.
● Limitations:
☆ A retrospective nature
☆ Small sample size
☆ Relatively limited followup.
☆ Study encompassing all cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis Although evidence does not support treating asymptomatic bacteriuria
☆ The manner in which monitoring and surveillance of UTIs should occur is not clear
☆ The effectiveness of prophylactic antibiotics in those patients is not clear
Level: 2
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
1. Please summarise this article. 2. What is the level of evidence provided by this article?
Please summarise this article
Introduction:
UTI is the most common infections post-transplant with variable incidence range 10-98%, this discrepancy due to different UTI definitions, diagnostic protocols, antibiotic prophylaxis used among studies and is associated with worse patients and graft survival.
UTI is defined as the presence of > 105 CFUin a proper urine sample (early morning sample, or from a sterile catheter) associated with upper or lower urinary tract symptoms. Definitions of UTI by American Society of Transplantation:
Asymptomatic bacteriuria with no urinary or systemic symptoms of infection.
Acute simple cystitis with Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter.
Acute pyelonephritis/ complicated UTI with Fever, chills, malaise, hemodynamic instability, or leukocytosis; flank/allograft pain; or bacteremia with same organism as in urine.
Recurrent UTI if more than three UTIs in previous 12-month period.
Most renal transplant recipients the classical symptoms may not occur due to immunosuppressive therapy and kidney denervation, and UTI may present only with graft dysfunction, mild febrile illness or urosepsis.
The most common organisms found after transplantation are either gram negative (E coli, Klebsiella, and Pseudomonas aeruginosa) or gram positive (Enterococcus faecalis) Gram negative pathogens are more common (E coli is the commonest organism isolated) than gram positive ones.
The incidence of isolation of multi-drug resistant bacteria(ESBL Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae) was more common in transplant recipients compared to general population.
Screening using simple urine culture is recommended in early transplant period. Pre-operative risk factors for UTI post -transplant:
Foley’s catheter for prolonged time. Post-operative risk factors:
Excessive immunosuppression.
Acute allograft dysfunction
Allograft rejection.
Aim of the study:
Identify the prevalence and risk factors of UTIs post-transplant UTIs.
Assess the effect of UTIs on renal function and effect of UTIs on allograft function at 2 years post-transplant.
Identify and qualify the causative organisms, and antibiotics sensitivities.
Methods:
This was a retrospective observational study. It was conducted at a quaternary level hospital in Royal Brisbane and Women’s Hospital (RBWH), Australia.
Those patients with acute post-transplant follow-up were provided at RBWH from July 1st, 2011, to July 1st, 2016. Inclusion criteria:
All patient >16 yrs. received their transplant at RBWH and being followed at the center for the last 2 years.
All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant. Exclusion criteria:
Patients not completing their 2 years follow up at RBWH.
Patient received their transplant before or after the study time period. UTI defined as a positive bacteriuria and received one or two courses of antibiotics, thus all the categories of UTI by the American Society of Transplantation Infectious Diseases Community of Practice were included.
The patients divided in two groups UTI and No UTI groups, UTI group sub-classified into cystitis or complicated UTI (systemic symptoms and a clinical profile mandating admission to hospital for parenteral antibiotic therapy).
72 patients include in this study had received their first renal transplant, 55 deceased donor, 7 living donor, and 10 with kidney-pancreas transplantation.
All base line characteristics were comparable among groups, including the immunosuppressive protocol, the indwelling catheter, and DJ stent times to remove them…etc.
Results:
20 patients experienced UTI during the study period (27.8% incidence). 8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
Among the UTI cohort group 77 events were reported:
The most common organisms are E. coli, klebsiella sp, pseudomonas.
55% (11/20) of the patients had at least one episode of complicated UTI/pyelonephritis, 45% (9/20) had at least one simple cystitis episode.
8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
The antibiotics used in treatment of UTI episode were penicillin and cephalosporin in 49% and 36%, respectively.
TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal in our cohort (66/71 = 93%)
Additional prophylactic antibiotics (6/7 with nitrofurantoin) were received by 35% of the UTI sub-group.
Discussion:
The incidence of UTIs in renal transplant patient was recorded at 27.8%. Similarities rates have been shown in other studies.
The risk factors identified in this study are like other studies.
They include the female gender and age. Surprisingly, pre-existing history of UTI and urogenital abnormality were not found to be risk factors. Low rates of E. coli bacteremia were noted, and no patients died because of UTI.
Trimethoprim usage for pneumocystis did not offer protection against UTI. In this study, UTIs affected the real function acutely during the episode. It did not impair renal function at two years post-transplant. The effectiveness of prophylactic antibiotics, impatient with frequent or recurrent UTIs was not clear.
It is difficult to generalize patients’ long-term allograft function using data two years post transplantation, but it may indicate the trend.
Risk factors and outcome results are:
On univariate analysis, risk factors for developing UTI are DM, old age and female sex, but type of transplant, HLA mismatch are not.
On adjusted analysis, female gender, and age) were statistically significant risk factors, all other variables were not statistically significant.
Despite acute kidney injury encountered with each UTI episode, no change in serum creatinine and GFR among all groups at 2 years.
Use of trimethoprim for Pneumocystis prevention did not provide protection. Study limitations: Retrospective nature, small sample size and relatively limited follow-up (only two years).
Study strength: All forms of UTI including asymptomatic bacteriuria were treated, it identifies the risk factors that is consistent with previous studies. Conclusion: The study emphasizes the risk factors of UTI post-transplant, and the SMX-TMP is not protective of UTI.
In a retrospective research, antibiotics were not accurately defined.
The study highlights the concept of prophylactic antibiotics in conjunction with SMX-TMP.
Antibiotic prophylaxis for UTIs offers perspective on risk factor and treatment.
What is the level of evidence provided by this article?
A retrospective cohort study ,Level of evidence II .
Urinary tract infections (UTI) are considered the commonest post renal transplant infections ranging between10 and 98%. The cause of discrepancy is attributed mainly to the availability of the diagnostic tools and prophylactic measures. After long practice finally the last updates by the American Society of Transplantation Infectious Diseases Community of Practice 2019 guidelines managed to establish clear definitions for all UTI syndromes particularly: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), as well as recurrent UTI.
Unfortunately, the common ‘classical’ symptoms of UTI in the form of urinary frequency, dysuria, urgency or suprapubic pain, mostly don’t exist owing to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters. Thus the presentation may be vague as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine, highlighting the routine outpatient dipstick testing is mandatory in this critical population.
The most common organism encountered is Escherichia coli followed by other common enteric organisms as Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.Risk factors may vary from preoperative considerations as female sex, diabetes mellitus and the presence of urological abnormalities. Could be also intraoperative due to the use of ureteric stents and prolonged indwelling bladder catheterisation. While postoperatively, the exposure to acute allograft dysfunction and rejection necessitating the excessive use of immunosuppression.
It is evident that the occurrence of UTIs in this population is hazardous as it poses the patients to the risk of increased morbidity, hospitalisation rates besides acute allograft dysfunction. The question then is does it affect long-term allograft function or reduce allograft or patient survival.
A huge study conducted by the United States Renal Data System registry for infections for more than 60,000 renal transplant recipients from 2000 to 2011 in the first year post renal transplantation concluded that 32% of patients had a UTI in the first year which was associated with a 41% increased relative risk of death.
Methods
This study is a retrospective observational one performed at the Royal Brisbane and Women’s Hospital (RBWH) for 2 years duration post renal transplantation.
The study population involved all adult renal transplant recipients (> 18 years old even simultaneous kidney-pancreas transplantation) as well as those having their post-acute transplant follow-up at RBWH from July 1st 2011 to July 1st 2016.
UTI is defined by the existence of bacteriuria proved by laboratory reports and receipt of one or more courses of antibiotics. Importantly, three consecutive sera creatinine were needed; ‘Pre-UTI’ was within 3 months before the episode, the ‘UTI episode’ within 2 weeks of recorded bacteriuria and ‘post UTI’ by 15 days to 3 months post UTI.
All UTI episodes were included from 1 month post renal transplantation up to 2 years.Severity was classified by the presence of simple cystitis or by complicated UTI/pyelonephritis requiring hospital admission for parenteral antibiotic therapy.
Statistical analysis were carried out using STATA version 15, Pearson’s Chisquared test and Fisher’s exact test.P-values less than 0.05 were significant.
Results
A total number of 72 patients (55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants) were first renal transplant.
There was no association between the occurrence of UTI and induction therapy even those who received thymoglobulin induction which were only 3 patients (p = 0.20).
The mean age at transplantation was 45.5 years (median: 47, range: 17–71). All patients removed catheter 3–5 days post transplantation. Also, ureteric stents were removed 4–6 weeks post operatively.
In this study, 20 patients had at least one UTI over the study period with incidence rate for a UTI was 27.8%.The mean number of UTIs per person among all patients was 3.85. About 55% of the patients (11/20) in the UTI subgroup had at least one episode of complicated UTI/pyelonephritis.The other group 45% (9/20) had at least one simple UTI episode. Total of 33.8% of the UTI episodes were considered complicated UTI/pyelonephritis (26/77). It was found that only 8% (6/77) ofblood cultures obtained at time of a UTI episode were positive.
ESBL-producing organism in 3.9% of urine cultures (3/77) was the most common. It had the feature of response to penicillin, gentamicin and carabepenem.
The study also confirmed that older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) are still considerable risk factors for developing UTI. In contrast,HLA mismatches and strong pre-existing history of UTIs were not found to be risk factors anymore.
Each UTI episode was associated with a mean increase in serum creatinine of 21 micromol/L (14.4%, SEM 5.20) andstatistically significant (p = 0.027). While after resolution of the UTI, the estimated mean reduction was 16 micromol/L (9.1%, SEM 6.23) reduction in serum creatinine with statistical significance (p = 0.076).
Fortunately, there was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between both groups with complicated UTI/pyelonephritis and simple UTI (p = 0.331) or eventhe rest of the whole cohort (p = 0.814).
Discussion
Similar to other studies, this work confirmed the high incidence of post renal transplant UTI about 27.8%. Concerning the knownrisk factors for developing a UTI as other studies only Female gender and age were the only significant risk factors while pre-existing history of UTI or urogenital abnormality are no more considered risk factors.
In 2016, a study elaborated that early removal of ureteric stents at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks while our study found that they were not linked at all.
Our study fortunately proved low rates of ESBL-producing organisms UTI or bacteremia besides no deaths were encountered due to UTI. The use oftrimethoprim for Pneumocystis prophylaxis was not associated with more protection against UTIs in our patients even when being used by 93% of patients at doses considered prophylactic for UTIs.
Among all groups, no significant difference in baseline serum creatinine levels was demonstrated.
Limitations were mainly being retrospective with small sample size and relatively limited follow up duration. In order to assess the patients’ long-term allograft function 2 year study duration is definitely not satisfactory.
Strengths were the wide application of the definition of UTI in all cases.
Conclusion
Other extensive studies are needed particularly to reevaluate the risk factor profile, treatment of UTIs and the doubtful benefit of antibiotic prophylaxis for UTIs.
UTI is the most common infection after renal transplantation, with an estimated 10-98% incidence. Updated 2019 guidelines unify definitions for asymptomatic, acute simple cystitis, acute pyelonephritis, complicated UTI, and recurrent UTI. Risk factors for post-transplant UTIs include pre-operative (host) factors, intra-operative factors and post-operative factors.
Methods:
This study included adult patients who received a renal transplant and had post-transplant care for 2 years, and defined UTI as the presence of bacteriuria on laboratory reports and receipt of antibiotics. Statistical analysis was performed using STATA version 15, with Pearson’s Chisquared test and Fisher’s exact test for non-correlated data.
Result :
72 patients were reviewed posttransplantation, with 95.7% receiving intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate.
Congenital/genetic and metabolic/vascular diseases were the most common causes of end-stage kidney disease leading to transplantation, with glomerulopathy also common. All patients had an indwelling catheter to measure urine output and a ureteric stent inserted. The mean number of UTIs per person in the UTI sub-group was 3.85, and 55% of the patients had at least one episode of complicated UTI/pyelonephritis. TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal, and additional prophylactic antibiotics were received by 35% of the sub-group as an adjunct. Older age, female gender, hyperglycaemia .
There was no significant difference in serum creatinine and estimated glomerular rate (eGFR) between those with and without a UTI, and no statistically significant difference between those with a complicated UTI/pyelonephritis and the rest of the cohort.
Discussion:
This study highlights the incidence of UTIs in a renal transplant population with 27.8% of patients experiencing a UTI. It identified risk factors for developing a UTI, such as female gender and age, and a pre-existing history of UTI or urogenital abnormality. Stent usage was associated with lower rates of UTI, and trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs. There was no significant difference in baseline serum creatinine levels between the two subgroups.
This study examined renal function at 2 years post-transplant for those experiencing a complicated UTI/pyelonephritis. The time-point of 2 years was chosen as a reference point due to the increased risk of UTIs in the initial 12 months and high levels of immunosuppression employed in this period.
Many of the reported risk factors for UTIs in this population cannot be mitigated, and vigilance and monitoring for hyperglycaemia is important for cardiovascular benefits. However, the effectiveness of prophylactic antibiotics is not clear.
Conclusion : This study adds to the growing body of work around UTI management in the kidney transplant population, highlighting that UTIs are common and risk factors include female gender, older age and hyperglycaemia.
What is the level of evidence provided by this article?
· Urinary tract infections (UTIs) are the most common infections after renal transplantation, with an estimated incidence of 10-98%. · The 2019 guidelines from the American Society of Transplantation Infectious Diseases Community of Practice have attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI. · Risk factors for the development of a post-transplant UTI can be divided into pre-operative (host) factors, intraoperative factors, and postoperative factors. · Preoperative factors include female sex, diabetes mellitus, and the presence of urological abnormalities, intraoperative factors include kidney transplantation from a deceased donor, the use of ureteric stents, and prolonged indwelling bladder catheterization, and post-operative factors include acute allograft dysfunction and rejection. · The 2009 KDIGO guidelines recommend TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.· Recent studies have shown a rising prevalence of resistant organisms in those with UTIs. · It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival. · This study aimed to identify the prevalence and risk factors for post-transplant UTIs and assess their effect on renal function during a UTI episode and if it resulted in declining allograft function at 2 years post-transplant.
Methods
· Retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital. · Patient charts, pathology records, and dispensing histories were reviewed as part of this study and all UTIs from 2 years post-transplantation were captured.
Results
· Older age, female gender, hyperglycemia, and acute rejection episodes were risk factors for developing a UTI. · Serum creatinine increased during a UTI episode and decreased after. · Common organisms accounted for 82% of UTIs, with 70% requiring only a single course of antibiotic treatment. · TMP/SMX prophylaxis did not influence the rate of UTI.
Discussion
· This study highlights the incidence of UTIs in a renal transplant population, with 27.8% experiencing a UTI.
· Risk factors for developing a UTI included female gender and age, early ureteric stent removal, low rates of UTI or bacteremia caused by ESBL-producing organisms, and trimethoprim usage for Pneumocystis prophylaxis.
· UTIs acutely affected renal function during an episode but did not impair overall renal function at 2 years post-transplant.
· Early detection and aggressive treatment of asymptomatic bacteriuria led to a milder profile of UTIs in our cohort, with only 8% of all UTI episodes having co-existing bacteremia and no statistically significant difference in renal function at 2 years post-transplant.
· Risk factors such as gender and age cannot be mitigated.
· Vigilance and monitoring for hyperglycemia are important for cardiovascular benefits.
· This study examined the effectiveness of trimethoprim prophylaxis and prophylactic antibiotics in reducing UTIs in the kidney transplant population.
· Risk factors were female gender, older age, and hyperglycemia.
· UTIs did not affect renal function at 2 years post-transplant, and ESBL organisms were relatively uncommon
· The evidence does not support treating asymptomatic bacteriuria in its own right, but clinicians would treat it if it is associated with an unexplained rise in serum creatinine.
· The study design was the retrospective, small sample size and limited follow-up, but the results were indicative of important trends.
Conclusion,
· There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those with and without a UTI.
UTIs are the most common of infections after KTX. The serious consequences of UTIs in this cohort are increased morbidity & hospitalization rates, & acute allograft dysfunction. Overall patient & graft survival may be hampered by UTIs. The estimated incidence of UTIs in post-KTX patients is between 10 & 98%.
Due to immunosuppression & surgical denervation of the transplanted kidney & ureters, the “traditional” UTI symptoms (frequency, dysuria, urgency, or pain) are frequently absent in the KTX population. Instead, UTIs may manifest as a new febrile illness, urosepsis, or an asymptomatic increase in serum creatinine.
In both non-TX & TX populations, gram-negative rods are the primary bacteria responsible for UTIs. The most prevalent uropathogen is E. coli, while common intestinal pathogens include Klebsiella pneumoniae, Pseudomonas aeruginosa, & Enterococci.
Aims of the study
To identify the prevalence & risk factors for post-transplant UTIs.
To assess UTIs’ effect on renal function during a UTI episode & if they result in declining allograft function at 2 years post-transplant.
To quantify the causative organism, the class of antibacterial drug employed for each UTI episode & utilization rates of TMP/SMX) prophylaxis.
Methods:
A retrospective study of 72 KTX patients over a 5-year period who were managed at the Royal Brisbane & Women’s Hospital. All UTIs from 2 years post KTX were reviewed.
Results
20 (27.8%) of these individuals had at least one UTI. Unadjusted analysis revealed that AR episodes, hyperglycemia, female gender, and older age were risk factors for having a UTI. On adjusted analyses, female gender and age were statistically significant risk variables for a UTI.
During UTI episodes, S. creatinine levels increased by 14.4% (statistically significant), & they dropped by 9.1% (moving toward statistical significance) following the episode.
82% of UTI episodes were caused by common pathogens (E. coli & Klebsiella pneumoniae), & 70% of UTI cases only required a single course of antibiotic therapy. In the majority of UTIs, either a penicillin (49%) or a cephalosporin (36%) antibiotic class was utilized.
> 90% of the group used TMP/SMX prophylaxis for PCP prophylaxis, which had no effect on the prevalence of UTI.
Discussion
The study emphasizes the prevalence of UTIs in KTX population, with a UTI occurring in 27.8% of this cohort. Comparable rates have been shown in other research, supporting the idea that UTI is still the most prevalent infection following KTX.
The study identified several characteristics that have been shown in prior studies to increase the likelihood of getting a UTI.
Although most patients receiving trimethoprim, it did not provide protection against UTIs in this study. This raises intriguing questions about the therapeutic efficacy of trimethoprim for UTI prevention in the population of KTX.Renal function was acutely impacted by UTIs during an episode, but after 2 weeks, it returned to normal. Importantly, 2 years after the transplant, UTIs had not negatively impacted overall renal function.
Several risk factors for UTIs in this population, like age & gender, are insurmountable obstacles.
Hyperglycemia in the transplant group should be closely watched because it has positive effects on the heart in addition to being a predictor of higher UTI risk.
Although many doctors would treat asymptomatic bacteriuria if it was also accompanied by an unexplained increase in serum creatinine, the study acknowledges that the evidence does not support treating asymptomatic bacteriuria in itself.
Conclusion
The results of this study provide an intriguing viewpoint on the risk factor profile, treatment, & idea of antibiotic prophylaxis for UTIs. They are valid for a similar intensively monitored minimal immunosuppression TX population.
======================= 2.What is the level of evidence provided by this article?
UTI is the most common infections post-transplant with variable incidence range 10-98%, this discrepancy due to different UTI definitions, and diagnostic protocols, and antibiotic prophylaxis used among studies.
Definitions of UTI by American Society of Transplantation:
Asymptomatic bacteriuria= No urinary or systemic symptoms of infection.
Acute simple cystitis= Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter.
Acute pyelonephritis/ complicated UTI= Fever, chills, malaise, haemodynamic instability, or leukocytosis; flank/allograft pain; or bacteremia with same organism as in urine.
Recurrent UTI= ≥3 UTIs in prior 12 month period.
Pre-operative risk factors for UTI post transplant: Female sex. Diabetes mellitus. Urological abnormalities. Intraoperative risk factors: Deceased donor. Double J catheter. And Foley’s catheter for prolonged time. Post-operative risk factors: Excessive immunosuppression. Acute allograft dysfunction Allograft rejection. Aim of the study: To identify the prevalence of post transplant UTIs. To identify the risk factors for post-transplant UTIs. To assess effect of UTIs on renal function. To assess effect of UTIs on allograft function at 2 years post transplant. To identify and qualify the causative organisms, and antibiotics sensitivities. Methods:
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia, that receives transplanted patients for management in the early post-operative period.
Those patients with acute post-transplant follow-up was provided at RBWH from July 1st 2011 to July 1st 2016.
Inclusion criteria: All patient >16 yrs received their transplant at RBWH and being followed at the center for the last 2 years. All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant. Exclusion criteria: Patients not completing their 2 years follow up at RBWH. Patient received their transplant before or after the study time period.
UTI defined as a positive bacteriuria and received one or two courses of antibiotics, thus all the categories of UTI by the American Society of Transplantation Infectious Diseases Community of Practice were included.
The patients divided in two groups UTI and No UTI groups, UTI group sub-classified in to cystitis or complicated UTI (systemic symptoms and a clinical profile mandating admission to hospital for parenteral antibiotic therapy).
72 patients include in this study had received their first renal transplant, 55 deceased donor, 7 living donor, and 10 with kidney-pancreas transplantation.
All base line characteristics were comparable among groups, including the immunosuppressive protocol, the indwelling catheter, and DJ stent times to remove them…etc.
Results:
20 patients experienced UTI during the study period (27.8% incidence).
8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
Among the UTI cohort group 77 events were reported:
The most common organisms are E.coli, klebsiella sp, pseudomonas.
55% (11/20) of the patients had at least one episode of complicated UTI/pyelonephritis, 45% (9/20) had at least one simple cystitis episode.
8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
The antibiotics used in treatment of UTI episode were penicillin and cephalosporin in 49% and 36%, respectively.
TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal in our cohort (66/71 = 93%)
Additional prophylactic antibiotics (6/7 with nitrofurantoin) were received by 35% of the UTI sub-group.
Risk factors and outcome results are:
= On univariate analysis; risk factors for developing UTI are: DM, old age and female sex, but type of transplant, HLA mismatch are not. = On adjusted analysis, female gender and age) were statistically significant risk factors, all other variables were not statistically significant. = In spite of acute kidney injury encountered with each UTI episode, no change in serum creatinine and GFR among all groups at 2 years. = Use of trimethoprim for Pneumocystis prevention did not provide protection. Study limitations: Retrospective nature, small sample size and relatively limited follow-up (only two years). Study strength: all forms of UTI including asymptomatic bacteriuria were treated, it identifies the risk factors that is consistent with previous studies. Conclusion: The study emphasizes the risk factors of UTI post-transplant, and the SMX-TMP is not protective of UTI. The study highlights the concept of prophylactic antibiotics in conjunction with SMX-TMP.
What is the level of evidence provided by this article? Level of evidence II C – outcome retrospective cohort study.
Summary. Background
UTI are most common infections in post-transplant period with incidence rates ranging between 10-98%.
Classical UTI symptoms of frequency, dysuria and suprapubic pain are usually absent in kidney recipient due to innervation of the kidney and ureters.
Thus in kidney recipients UTI may present as new febrile illness, asymptomatic rise of serum creatinine and urosepsis.
GN rods are the most common causative pathogens with common organisms being E.coli, klebsiella, pseudomonas aeroigenosa and enterococcus species.
Risk factors for developing UTI can be grouped into:
Intra-operative – kidney transplantation from deceased donor, prolonged indwelling catheter and ureteric stent
Post-transplant – allograft rejection and excessive use of immunosuppressive therapy.
KDIGO 2009 guidelines recommends PCP prophylaxis with TMP/SMX for at least 6 months.
There has been a rise of resistant UTI organisms whilst still on prophylaxis.
UTI’s are associated with increased mortality, morbidity and allograft dysfunction.
Aim of the study
To identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode.
To assess if UTI resulted in declining allograft function at 2years post-transplant.
To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode. Utilisation rates of TMP/SMX prophylaxis were also investigated
Methodology
Retrospective observational study.
Inclusion criteria
All adult patients returning to our centre who had their post-transplant care with us for 2 years from their renal transplant date and within the specified time frame of 1st July 2011 to 1st July 2016.
Exclusion criteria
Those patients returning to our centre within the above timeframe but not completing their 2 years of post-transplant care with us, as well as those who received their transplant outside the specified time frame.
Definition of terms
UTI was defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
This thus included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
Results
72 patients were recruited- 55DCD, 7 LKD and 10 simultaneous kidney-pancreas transplant.
All received induction therapy with either basiliximab or ATG with methylprednisolone.
Maintenance therapy was triple therapy.
All patients had an indwelling catheter that was removed 3-5 days after transplant.
All patients had a ureteric stent that was removed 4-6 weeks after transplant.
20/72 had a UTI with incidence rate of 27.8%.
11/20 (58%) had a complicated UTI.
ESBL producing organism was isolated in 3.9%.
66/71 were on TMP/SMX prophylaxis.
Risk factors associated were female gender, hyperglycaemia and acute rejection episodes.
With each UTI episode there was a mean increase in Scr that decline after the episode.
There was no statistical difference in eGFR between those with UTI and those without from baseline to 2 years post-transplant.
Discussion
This study identified risk factors for developing UTI similar to other studies.
TMP/SMX use didn’t confer protection for UTI in this study.
In this study UTI acutely affected renal function with resolution to baseline 2 weeks post-UTI.
UTI didn’t impair renal function at 2 years post-transplant.
Limitations
The study design this was a retrospective observational study.
The sample size was small.
There was limited followup of the patients.
Strengths.
They utilised an all encompassing UTI definition.
Background
Urinary tract infections (UTI) are common infections in renal transplant recipients. The “classical” symptoms of UTI are usually absent in renal transplant recipients due to immune suppression and surgical denervation of the transplanted kidney and ureters. Therefore, UTI, in a renal transplant recipient may present as a new febrile illness, urosepsis, or an asymptomatic rise in serum creatinine. There are a wide variation of UTI syndromes, which include asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI) and recurrent UTI.
The main pathogens causing UTIs in both non-transplant and transplant patients are gram-negative rods, including E. coli, K. pneumoniae, P. aeruginosa and Enterococci species. Unfortunately there is an increasing incidence and prevalence of MDR pathogens globally. Despite the use of TMP/SMX universally for the first six months post-transplant, there is an increasing incidence of UTIs, portraying the increasing resistance of these organisms to TMP/SMX.
Risk factors for developing UTI after transplantation include:
Preoperative factors:
Female sex
Diabetes mellitus
Presence of urological abnormalities.
Intraoperative factors:
Kidney transplantation from deceased donor
Use of ureteric stents
Prolonged indwelling bladder catheterization
Postoperative factors:
Acute allograft dysfunction and rejection
Increased immune suppression due to rejection episodes.
For kidney transplant recipients UTIs are associated with increased morbidity and hospitalization.
The aim of this study was to identify the prevalence and risk factors for post-transplant UTIs and assess the UTIs effect on renal function during a UTI episode. It also aimed to assess if the UTI resulted in declining allograft function at two years post-transplant.
Methods
This was a retrospective observational study. It was conducted at a quaternary level hospital in Brisbane, Australia. All adult patients who were followed up at the hospital for two years after the renal transplant were included. The patients excluded were patients who had not completed two years post-transplant care with the hospital, and those who received the transplant outside the specified timeframe.
UTI was defined as the presence of bacteriuria on lab reports and receipt of one or more courses of antibiotics. This definition included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics. Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine, and was clinically necessary to treat.
Results
72 patients were reviewed after transplantation over a five-year duration. There were 55 deseased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney and pancreas transplants. Induction therapy included either IV basiliximab or thymoglobulin and methylprednisolone together with tacrolimus and mycophenolate. The mean age of transplantation was 45.5 years. All patients had an indwelling catheter to measure urine output, and this was routinely removed 3 to 5 days after transplantation. All patients had a ureteric stent inserted and it was routinely removed 4-6 weeks after the procedure, unless the patient developed an early UTI, in which case it was removed earlier.
20 patients experienced at least one UTI over the study duration. 55% of the patients in the UTI sub group had at least one episode of complicated UTI. The remaining 45% in the sub group had at least one simple UTI episode. E. coli was detected in 3.9% of urine cultures and all the isolates were sensitive to penicillin, gentamicin and carbapenem. TMP/SMX treatment was universal, unless the patient had side effects or an allergy. With each UTI, episode the serum creatinine increased by 21 µmol/l.
Discussion
The incidence of UTIs in renal transplant patient was recorded at 27.8%. Similarities rates have been shown in other studies. The risk factors identified in this study are similar to other studies. They include the female gender and age. Surprisingly, pre-existing history of UTI and urogenital abnormality were not found to be risk factors. Low rates of E. coli bacteremia was noted and no patients died as a result of UTI. Trimethoprim usage for pneumocystis did not offer protection against UTI. In this study, UTIs affected the real function acutely during the episode. It did not impair renal function at two years post-transplant. The effectiveness of prophylactic antibiotics, impatient with frequent or recurrent UTIs was not clear. It is difficult to generalize patients’ long-term allograft function using data two years post transplantation but it may indicate the trend.
Study Limitations
Retrospective study
Short sample size
Relatively limited follow up
Level of Evidence
This is a retrospective study. LOE II
UTI is the most common early post-transplant infection and is associated with wores patietn and graft survival
UTI is defined as the presence of > 105 CFU in a proper urine sample (early morning sample, or from a sterile catheter) associated with upper or lower urinary tract symptoms, on the other hand if the patient is asymptomatic the condition is termed ASB.
Categories of UTI includes asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis and recurrent UTI.
In renal transplant recipients the classical symptoms may not occur due to immunosuppressive therapy and kidney denervation, and UTI may present only with graft dysfunction, mild febrile illness or urosepsis
The most common organisms found after transplantation are either gram negative (E coli, Klebsiella, and Pseudomonas aeruginosa) or gram positive (Enterococcus faecalis)
Gram negative pathogens are more common (E coli is the commonest organism isolated) than gram positive ones
The incidence of isolation of multi-drug resistant bacteria (ESBL Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae) was more common in transplant recipients compared to general population
Screening using simple urine culture is recommended in early transplant period
Risk factors of UTI includes older age, female gender, DM, urologic abnormalities, deceased donor transplantation, prolonged use of urinary catheterization, the use of ureteric stents, graft dysfunction and AR.
The current study is a retrospective study (level of evidence III) evaluating 72 renal transplant recipients treated in the Royal Brisbane and Women’s Hospital and follow them over a 2 years period after transplantation, regarding the incidence and risk factors for UTI, graft function during, after a UTI episode and 2 years after transplantation and the antibiotic susceptibility of the organisms isolated, and whether the incidence of UTI changed by the use of SMX-TMP prophylaxis or not.
Results
27.8% of patients had at least one UTI.
Risk factors for UTI includes older age, female gender, hyperglycemia, and AR episodes
During episode of UTI there is an increase of serum creatine around 14.4% followed by reduction around 9.1% after treatment of UTI, with no long term effect on graft function.
82% of the organisms isolated were E coli and Klebsiella
Single antibiotic was needed in 70% of UTI cases
The antibiotics used in treatment of UTI episode were penicillin and cephalosporin in 49% and 36%, respectively.
The incidence of UTI was not affected by the use of SMX-TMP prophylaxis
Conclusion
No long term effect of UTI episodes on graft function after 2 years of transplantation in the current study
SMX-TMP prophylaxis did not decrease the incidence of UTI episodes, and may increase the risk of isolation of drug resistant strains
Background:
After kidney transplantation, urinary tract infections (UTI) account for 10–98% of infections. Variations in study definitions, diagnostic criteria, and prophylactic antibiotic use explain the large range. Hence, UTI diagnosis in renal transplant patients has been inconsistent till recently. The 2019 American Society of Transplantation Infectious Diseases Community of Practice recommendations strive to standardize terminology for all UTI symptoms, including asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurring UTI.
Methods:
RBWH, a quaternary hospital in Brisbane, Australia, undertook retrospective observational research. Early postoperative transplant patients are treated here. All adult patients (18+) who got a renal transplant (including simultaneous kidney-pancreas transplantation) and received post-acute transplant follow-up at RBWH from July 1, 2011 to July 1, 2016, had their baseline demographics gathered.
Results:
20 (27.8%) of these individuals developed UTIs. In unadjusted analysis, UTI risk variables were older age, female gender, hyperglycemia, and acute rejection episodes. In adjusted analyses, female gender (OR 4.93) and age (OR 1.03) were significant UTI risk variables. During a UTI episode, serum creatinine increased by 14.4% (SEM 5.20), which was statistically significant (p = 0.027), and it decreased by 9.1% (SEM 6.23) thereafter, heading toward significance.
(p = 0.076). 82% of UTIs were caused by Escherichia coli and Klebsiella pneumonia, and 70% required just one antibiotic course. Most UTIs utilized penicillin (49%) or cephalosporin (36%). TMP/SMX prophylaxis for Pneumocystis carinii pneumonia did not affect UTI rates in > 90% of the group.
Discussion:
The research found UTI risk variables that have been shown in prior studies.
Female gender and age were the only risk variables that achieved statistical significance in the adjusted analysis. Surprisingly, a pre-existing UTI or urogenital abnormalities was not a risk factor in the unadjusted analysis.
In this trial, UTIs rapidly impaired renal function, but renal function returned to baseline after 2 weeks. UTIs did not affect renal function two years post-transplant.
A wide definition of UTI included people who were clinically regarded to need treatment, not simply symptomatic patients.
Due to early detection and aggressive treatment of clinically significant asymptomatic bacteriuria, our cohort had a milder profile of UTIs, with only 8% of UTI episodes having co-existing bacteremia and no statistically significant difference in renal function at 2 years post-transplant for those with complicated UTIs.
UTI is the most common infection post-KT with an estimated incidence of 10-98%.
Wide incidence variation is due to;
a) Inconsistent definitions and diagnostic criteria. b) A variable utilization rate of antibiotics.
The 2019 guideline of ASTID defines all UTI syndromes as
a) Asymptomatic bacteriuria. b) Acute simple cystitis (lower UTI). c) Acute pyelonephritis (complicated UTI) plus fever and chills. d) Recurrent UTI.
The classicalsymptoms of UTI (maybe absent in the immunocompromised patients);
a) Urinary frequency. b) Dysuria. c) Urgency or suprapubic pain. d) In immunocompromised patients may present as a new febrile illness, urosepsis, and or asymptomatic rise in S.Cr.
A urine dipstick is a routine for detecting asymptomatic bacteriuria in KTR.
The most common pathogens in KTR and in the general population are G-ve rods
a) E.coli. b) Klebsiella pneumonae. c) Pseudomonas aeroginosa. d) Enterococcus spp. e) MDR G-ve.
MDR G-ve
a) Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae. b) Carbapenem-resistant Enterbacteriaceae. Risk factors of UTI in KTR;
Pre-operative (host factor)
a) female sex. b) DM. c) Urological abnormality.
Intra-operative
a) Deceased donation. b) ureteric stents. c) Prolonged indwelling catheterization.
Post-operative factors
a) Acute allograft dysfunction. b) Rejection. c) Extensive immunosuppressants. KDIGO 2009 guidelines recommend TMP-SMX for prophylaxis against pneumocystis carinii for at least 6 months post-KT, (although proved by a recent study of the developing resistance whilst on prophylaxis).
UTI in KTR can cause morbidity, hospitalization, and acute allograft dysfunction.
A recent USRDSR from 2000-2011 for UTI incidence during the 12 months after KT demonstrates that 32% of patients had UTI in the first year and it was associated with a 41% increase in relative risk incidence of death.
Discussion
27% of the patients in this cohort experienced UTI, with a similar incidence rate among the other studies.
Risk factors
a) Female gender. b) Age. c) Stent usage (early removal of the stent is vital for reducing the rate of UTI).
There is a significant association between MDR and mortality.
TMP-SMX s not shown to reduce the incidence of UTIs.
UTIs in this cohort exhibit a milder course with only 8% of all UTIs having co-existing bacteremia and no significant renal affection at 2 years post-KT, compared to those experiencing complicated UTI.
A higher rate of complicated UTIs was seen in other studies, 13-24%.
Severe UTI and urosepsis have an adverse impact on long-term renal function.
Timepoint at 2 years was chosen to be a reference point, why?
a) There is a well-documented increased risk of UTIs in the initial 12 months post-KT, (due to surgical procedures in early Tx, and massive immunosuppressants). b) 2 years represents a reliable and accessible dataset in terms of dispensing and medical record accuracy. what is unclear in this study
Unclear the manner in which monitoring and surveillance of UTIs should occur, given the relative ineffectiveness at reducing UTIs demonstrated by trimethoprim prophylaxis and a non-significant difference in renal function at 2 years post-KT, between simple and complicated UTIs.
Unclear the effectiveness of the prophylactic antibiotics in those patients of frequent or recurrent UTI.
Limitations
Small-size study.
Retrospective study.
Relatively limited follow-up.
Strengths
Add to the growing body of work around UTI management in the KTR, by highlighting that UTIs are very common.
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
This is a retrospective observational study of 72 renal transplant patients over a 5-year period who were managed in Australia at the Royal Brisbane and Women’s Hospital. The study aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
1. The estimated incidence of UTI in post-transplant period ranges between 10 and 98%.
2. Classification of asymptomatic bacteriuria and UTI in renal transplant recipients according to American Society of Transplantation Infectious Diseases Community of Practice:
· Asymptomatic bacteriuria: No urinary or systemic symptoms of infection.
· Acute simple cystitis: Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter. · Acute pyelonephritis/ complicated UTI: Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain; or bacteremia with same organism as in urine. Dysuria, urgency, frequency, suprapubic pain may or may not be present. · Recurrent UTI: ≥3 UTIs in prior 12 month period. 3. Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant populations. Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species. 4. Risk factors for post-transplant UTI: a) pre-operative (host) factors: female sex, diabetes mellitus and the presence of urological abnormalities. b) intra-operative factors: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization. c) post-operative factors: acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes. UTI episodes in the study group(77 patients) a) Most common organisms: · E.coli; 41 (53%) · Klebsiella species; 22 (29%) · Pseudomonas aeruginosa; 4 (5%) · Enterococcus faecalis; 3 (4%) · ESCAPPM organisms; 3 (4%) · Culture negative; 2 (3%) · Other; 2 (3%) b) Number of antibiotics received per episode: · One; 54 (70%) · Two; 18 (23%) · Three; 5 (6%) c) Class of antibiotics used: · Penicillins; 38 (49%) · Cephalosporins; 27 (36%) · Fluoroquinolones; 12 (16%) · Carbapenems; 3 (4%) · Other; 14 (18%) Study’s Result and Discussion
1. With each UTI episode, there was a mean increase in serum creatinine of 21 micromol/L.
2. Female gender and age were the only risk factors for UTI.
3. Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in the study’s group.
4. UTIs acutely affected renal function dur- ing an episode, with renal function approaching baseline from 2 weeks post UTI.
5. UTIs did not im- pair overall renal function at 2 years post-transplant.
I like your well-structured detailed summary, limitations and strengths based on analysis and take home messages. Why level 3 evidence for this article?
Introduction: – UTI is the most common infection after renal transplantation. – It has significant consequences of UTIs with increase morbidity and hospitalization rates, acute allograft dysfunction. It may reduce graft and patient survival. – Updated 2019 guidelines AST/IDCP have attempted to unify definitions for all UTI syndromes. – E. coli is the most common uropathogen and MDR gram negative bacteria are increasing in number. – Multiple risk factors contribute to increase the risk. Study Aim: – Identify the prevalence and risk factors for post-transplant UTIs – Assess UTIs’ effect on renal function during a the episode and 2-years post-Tx. – Identify the causative organism, the class of antibacterial used. – Investigate the utilization rates of TMP/SMX prophylaxis. Methods: – Retrospective study over 5-year period (2011- 2016). – Included all adult patients (> 18 years old) who received a KT (including Simultaneous kidney- pancreas) whose post-acute transplant follow-up was provided at RBWH. – All-encompassing definition of UTI included. – To estimate renal function: 3 consecutive sera creatinine were reviewed. ‘Pre-UTI’; within 3 months prior to an episode, ‘UTI episode’ was within 2 weeks of a recorded bacteriuria and ‘post UTI’ was 15 days to 3 months post a UTI episode. – All UTIs from 2 years post transplantation were captured. – Patients classified according to the presence or absence of at least one UTI episode, and further classified according to UTI severity. – Patient charts, pathology records and dispensing histories were reviewed – All patients had an indwelling catheter removed at POD 3–5 days and ureteric stent removed at 4-6 weeks. Results: – Study included 72 patients, 52 (no UTI ), 20 (had UTI) – The incidence rate for a UTI was 27.8%. – E. coli and Klebsiella accounted for 82% of UTI episodes. – 33.8% of the UTI episodes were classified as a complicated UTI/ pyelonephritis – ESBL-E.coli isolated in very low rate. – On unadjusted analysis; older age, female gender, hyperglycaemia and acute rejection episodes were risk factors for developing a UTI. – Adjusted analysis showed female gender and age were statistically significant risk factors for a UTI. – Serum creatinine increased by 14.4 % during UTI episode and decline by 9.1% after treatment. – No significant change in serum creatinine and eGFR from baseline out to 2 years post-transplant between those with and without a UTI complicated or simple. – TMP/SMX prophylaxis for PCP did not provide protection against UTIs, despite 93% of patients on this treatment. -70% of UTI cases requiring only a single course of antibiotic treatment. -The antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. Conclusions: -There was no significant change in serum creatinine and eGFR from baseline to 2 years post-transplant between those with and without a UTI. -Prophylactic TMP did not confer protection against UTI. Limitations: retrospectivenature, small sample size and relatively limited follow up Level of evidence: retrospective observational study level 2
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions. I wish you could have highlighted that, “in this retrospective research, antibiotics were not accurately defined.”
Please summarise this article. Introduction
o UTIs are the most common of infections after renal transplantation with an estimated (incidence is 10-98%)
o The classical symptoms of UTI (urinary frequency, dysuria, urgency or suprapubic pain) are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters
o UTI in a renal transplant recipient may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine
o The main pathogens causing UTIs are gram-negative rods (in both the non-transplant and transplant populations)
o Escherichia coli is the most common organism and (other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species)
o UTIs increase morbidity and hospitalisation rates as well as acute allograft dysfunction
Risk factors for the development of a post-transplant UTI:
1. pre-operative (host) factors: female sex, DM, and the presence of urological abnormalities
2. intra-operative factors: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterisation
3. post-operative factors: acute allograft dysfunction and rejection and excessive immunosuppression (as a result of rejection episodes)
Definitions for UTI syndromes (American Society of Transplantation Infectious Diseases Community of Practice guidelines 2019):
1. Asymptomatic bacteriuria: no urinary or systemic symptoms of infection
2. Acute simple cystitis: dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter
3. Acute pyelonephritis/ complicated UTI: Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain; or bacteremia with same organism as in urine. Dysuria, urgency, frequency, suprapubic pain may or may not be present
4. Recurrent UTI: ≥3 UTIs in prior 12month period
Aim of the study: identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2years post-transplant
Methods
o This retrospective observational study was conducted at a quaternary hospital in Australia (the Royal Brisbane and Women’s Hospital) from July 1st 2011 to July 1st 2016
o 72 patients were reviewed post transplant over a 5-year period
o All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant
o They included all adult patients returning to theirr centre who had their post-transplant care with them for 2 years from their renal transplant date
Results
o 72 patients were followed post transplant over a 5-year period (all had received their first renal transplant; 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidneypancreas transplants
o 20 patients (27.8%) had at least one UTI
o Risk factors for developing a UTI on unadjusted analysis were Older age, female gender, hyperglycaemia and acute rejection episodes
o Female gender and age were statistically significant risk factors for a UTI on adjusted analysis
o There was a 14.4% increase in serum creatinine during a UTI episode, which was statistically significant
o Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment
o The antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs
o The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with >90% of the cohort using this treatment
Discussion
In this study, UTIs acutely affected renal function during an episode, with renal function approaching baseline from 2 weeks post UTI
UTIs did not impair overall renal function at 2 years post-transplant
The time-point of 2 years post-transplant was chosen as a reference point for a number of reasons:
1. There is a well documented increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial 3-6 months, due to the surgical procedure itself and high levels of immunosuppression employed in this period
2. From a pragmatic perspective, 2 years represented a reliable and accessible dataset in terms of dispensing and medical record accuracy
Limitations of the study:
1. Retrospective study
2. small sample size
3. relatively limited follow-up
Conclusionso No significant change in serum creatinine and eGFT from baseline to 2 years post-transplant between those with and without a UTI
What is the level of evidence provided by this article?II (retrospective observational study)
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions. I wish you could have highlighted that, “in this retrospective research, antibiotics were not accurately defined.”
-Summary Introduction
UTI represent the most common infection post renal transplant.
Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases
Community of Practice unified the definitions of the following Asymptomatic bacteriuria has no urinary or systemic symptoms of infection Acute simple cystitis presenting by dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent,nephrostomy tube,chronic urinary catheter Acute pyelonephritis (complicated UTI) presents with fever, chills, malaise, haemodynamic instability, or leukocytosis ; flank/allograft pain;or bacteremia with same organism as in urine with or without dysuria, urgency, frequency, suprapubic pain Recurrent UTI ≥3 UTIs in the last 12 month .
Classic manifestations of dysuria and suprapubic pain may be absent in transplated population due to the denervation of the renal graft and immunosuppressives intake .
Therefore in renal transplant recipients UTI can manifest by fever , urosepsis ,increased creat level ,thereby routine urine dipstick testing is crucial.
Gram negative organisms as Ecoli ,Klebseilla pneumoniae, Pseudomonus and Enterococci are the common pathogens to cause UTI in transplanted and non transplanted patients.
Multidrug resistance bacterial strains as extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae and carbapenem -resistant Enterobacteriaceae are emerging .
Risk factors :
-preoperative : female gender , diabetes mellitus and urological abnormalities.
-intraoperative: using a renal graft from a deceased donor, ureteric stents and prolonged indwelling bladder catheterisation
-postoperative: acute allograft dysfunction , rejection and excessive immunosuppression
2009 KDIGO guidelines recommends TMP/SMX for Pneumocystis carinii prophylaxis for at least 6
months after-transplant which lead to arising of resistant stains.
The sequelae of UTI in this group of patients is hazardous it can lead to increased morbidity and allograft dysfunction
Aim of the study is to detect the prevalence and risk factors for post-transplant UTIs and evaluate it’s impact on renal function during a UTI episode and if it can decrease allograft function at 2 years post-transplant. Methods
This is a retrospective study on 72 renal transplant recipients within 5-year period treated at
the Royal Brisbane and Women’s Hospital. Patient data including the charts, pathology records and histories were revised and all UTI cases 2 years after transplantation were included. Results
Of these patients, 20 had at least one UTI. Risk factors for UTI were old age , female gender ,hyperglycaemia and acute rejection episodes. There was a 14.4% statistical significant increase in serum creatinine during a UTI episode and a 9.1% nearly statisticaly significant decrease in serum creatinine after the UTI episode.
Common organisms (Escherichia coli and Klebsiella pneumoniae) representing 82% of UTI episodes with 70% of UTI cases requiring one course of antibiotic treatment. Antibiotics used were penicillin (49%) or cephalosporin (36%) . TMP/SMX used for Pneumocystis carinii pneumonia prophylaxis did not affect UTI rate as > 90% of the cohort used it . Discussion
This study confirmed that UTI is the most common infection after renal transplantation.
Regarding the risk factors it revealed that female gender and age were the only risk factors with statistical significance and a pre-existing history of UTI or urogenital abnormality were not found to be a risk factors.
One study demonstrated that early ureteric stent removal at 1 week was associated
with lower rate of UTIs compared to conventional removal at 4 weeks.
ESBL rate was low in the current study.
Trimethoprim use for Pneumocystis prophylaxis did not show to be protective against UTIs in
the included patients.
This study noticed that UTIs acutely affects renal function during an episode, with renal function nearly reaching baseline 2 weeks post UTI, meanwhile UTIs did not affect overall renal function at 2 years post transplant.
This could be explained by the broad UTI definition and the early detection and proper treatment of early ASB leading to milder forms of UTI .
Other studies showed that severe UTIs and urosepsis exert a negative impact on long-term renal function.
2 years period time point was chosen due to high UTI risk in the first year post transplant and in the first 6 months post transplant due to surgical procedures and extensive immunosuppression also due to more medical records accuracy for evaluation.
It is not known the efficient monitoring and surveillance of UTIs that need to be done in the view of relative ineffectiveness of trimethoprim in decreasing UTI and the non-significant difference in renal function at 2 years post-transplant between the simple UTI and complicated cases.
The efficiency of prophylactic antibiotics in patients with frequent or recurrent UTIs is unknown
Limitations are being retrospective including small, sample size and short follow up period .
Strength including all UTI definition involving all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis; that is representative of current treatment strategies for transplant recipients.
Conclusions
Serum creatinine and e GFR did not vary significantly from
baseline to 2 years post-transplant between those with and without a UTI.
Results provided by this study are suitable for low immunosuppressed transplanted cases .
Also acknowledged risk factors, treatment of UTIs and the antibiotic prophylaxis for UTI were well addressed
-level of evidence is II as a retrospective observational study
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Please summarise this article.
Background
Urinary tract infections (UTI) are the most common of infections after renal transplantation, with an estimated incidence of 10-98%.
The diagnosis of UTI has been fraught with inconsistencies due to insufficient definitions and diagnostic criteria.
2019 guidelines from the American Society of Transplantation Infectious Diseases Community of Practice have attempted to unify definitions for all UTI syndromes.
Gram-negative rods are the main pathogens causing UTIs, with Escherichia coli being the most common uropathogen and other enteric organisms such as Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.
MDR bacteria such as ESBL-producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae are also present in the Australasian region and require older antibiotics.
Risk factors for post-transplant UTIs include pre-operative (host) factors, intra-operative factors, and post-operative factors.
The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommend TMP/SMX prophylaxis for at least 6 months post-transplant.
Recent studies have shown a rising prevalence of resistant organisms in those with UTIs while on prophylaxis. It is unclear if UTIs impair longterm allograft function or reduce allograft or patient survival.
Classification of asymptomatic bacteriuria and UTI in renal transplant recipients
Asymptomatic bacteriuria
No urinary or systemic symptoms of infection.
Acute simple cystitis
Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter.
Acute pyelonephritis/ complicated UTI
Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain;or bacteremia with same organism as in urine Dysuria, urgency, frequency, suprapubic pain may or may not be present.
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH) in Brisbane, Australia.
Baseline demographics were collected for all adult patients (> 18 years old)who received a renal transplant and whose post-acute transplant follow-up was provided.
UTI was defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
Three consecutive sera creatinine were reviewed to estimate renal function at each time-point.
Patients were stratified into two groups according to the presence or absence of at least one UTI episode, and those with complicated UTI/pyelonephritis were defined as having a complicated UTI/pyelonephritis.
Statistical analysis was performed using STATA version 15.
Associations between categorical variables were examined using Pearson’s Chi-squared test, Fisher’s exact test, and log-binomial logistic regression.
This study was approved by the Royal Brisbane and Women’s Hospital Human Research Ethics Committee.
Over a 5 year period, 72 patients received their first renal transplant.
Induction therapy consisted of intravenous basiliximab or thymoglobulin and methylprednisolone, tacrolimus and mycophenolate.
20 patients experienced at least one UTI over the study period and the incidence rate for a UTI was 27.8% across the whole cohort.
55% of the patients had at least one episode of complicated UTI/pyelonephritis and 33.8% of the UTI episodes were classified as a complicated UTI/ pyelonephritis.
Only 8% of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
The most important details are that TMP/SMX prophylaxis was almost universal in the cohort, and additional prophylactic antibiotics were received by 35% of the UTI sub-group (7/20).
On univariate analysis, older age, female gender, hyperglycaemia, and acute rejection episodes were all risk factors for developing a UTI.
On adjusted analysis, female gender and age were statistically significant risk factors for developing a UTI.
Overall, there was no significant change in serum creatinine and estimated glomerular rate from baseline out to 2 years post-transplant between those with and without a UTI.
This study highlights the incidence of UTIs in a renal transplant population, with 27.8% experiencing a UTI.
Risk factors for developing a UTI included female gender and age, early ureteric stent removal, low rates of UTI or bacteremia caused by ESBL-producing organisms, and trimethoprim usage for Pneumocystis prophylaxis.
UTIs acutely affected renal function, but did not impair overall renal function at 2 years post-transplant.
Early detection and aggressive treatment of clinically significant asymptomatic bacteruria yielded a milder profile of UTIs.
Similar cohort studies have demonstrated higher rates of complicated UTI/pyelonephritis.
The time-point of 2 years post-transplant was chosen as a reference point due to the increased risk of UTIs in the initial 12 months post-transplant.
Risk factors such as gender and age cannot be mitigated, and vigilance and monitoring for hyperglycaemia is important for cardiovascular benefits.
Prophylactic antibiotics are not effective in those with frequent or recurrent UTIs. UTIs are common in the kidney transplant population, with female gender, older age and hyperglycaemia being risk factors.
93% of patients taking TMX-SMX prophylaxis did not confer protection against UTIs, and ESBL organisms were relatively uncommon at 3.8%.
Our findings offer an interesting perspective on the risk factor profile and treatment of UTIs, as well as the concept of antibiotic prophylaxis.
I like your well-structured detailed summary, level of evidence, analysis and conclusions. I understand why you have written, “in a retrospective research, antibiotics were not accurately defined.” Typing whole sentence in bold amounts to shouting.
UTI in KTR at a quaternary care center in Australia ⭐⭐⭐⭐Summary:
· UTI is the commonest infection after KT, it is still debatable that its induced acute allograft dysfunction may have poor consequences on both graft and patient outcome.
· The current study concluded that:
o Although UTI can cause acute graft dysfunction, the creatinine normalized mostly within 2 weeks of UTI and the long term GFR was not affected at 2 years of follow up.
o Most common isolated organism were Escherichia coli and Klebsiella pneumonia( 82% of UTI episodes). Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
o Use of prophylactic SMX-TMP did not decrease incidence of UTI. However, it still recommended since KDIGO 2009 recommendation.
o MDR bacteria as extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae are already present in Australia and often require the deployment of much older antibiotics, some of which are nephrotoxic, this may be related to immigration and fusion of plasmids from different starins.
· Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurrent UT.
· Pain and dysuria are often absent in the KTR due to the combination of immunosuppression medications and surgical denervation of the transplanted kidney and ureters. So UTI can be presented by fever, sepsis and rising creatinine (acute graft dysfunction).
· TMP can cause reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine.
· Risk factors for UTI: female gender, DM and presence of pre-existing urological abnormalities and recurrent UTI episodes, deceased donor, prolonged use of ureteric stents and indwelling bladder catheter, excess immunosuppression as frequent episodes of acute allograft dysfunction and use of ATG and MMF. ⭐⭐Level of evidence: retrospective observational study (level 2)
Points of weakness: being retrospective (no accurate definitions as any case treated with antibiotics whether acute simple cystitis, transplant pyelonephritis or asymptomatic bacteriuria was included).
Urinary tract infections in renal transplant recipients at a quaternary care center in Australia. Background.
UTI post kidney transplant is considered the most common infection in this group due to immunosuppreive state, multiple -comorbidities, use of ureteric stents, prolonged indwelling bladder catheterization and urinary tract procedure, the usual symptoms of UTI, which includes urinary frequency, dysuria, urgency or suprapubic pain, are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters, Escherichia coli is the most common uropathogen.
Using of TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant, lead to rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis, we should bear in mind that UTIs in this population are serious with increased morbidity and hospitalization rates, as well as acute allograft dysfunction but still unclear if UTIs impair long-term allograft function or reduce allograft
or patient survival. Aim of the work:
1-To identify the prevalence and risk factors for post-transplant UTIs, it is effect on renal function during a UTI episode. And if UTI resulted in declining allograft function at 2 years post-transplant.
2-To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode.
3-And utilization rates of TMP/SMX prophylaxis were also investigated. Methods.
A retrospective study of 72 renal transplant patients over a 5-year period who were managed at
the Royal Brisbane and Women’s Hospital. Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were included . Results:
1-There was no association with UTI for those that received thymoglobulin induction.
2-The incidence rate for a UTI was 27.8% across the whole cohort.
3-ESBL-producing organism is isolated in 3.9% of urine cultures.
4-Female gender (, hyperglycemia and acute rejection episodes were all risk factors for developing UTI.
5-There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
6-There was also no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI.
7-No effect from using TMP/SMX prophylaxis for Pneumocystis carinii pneumonia, which did not influence the rate of UTI, with > 90% of the cohort using this treatment. Conclusion:
UTI is the most common infection post KTX but with treatment of UTI, there is no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI, and no impact from using TMP/SMX prophylaxis on the incidence of UTI.
Level of evidence is 3 (a retrospective study).
What is your reason for allocating level 3 to this report? I like your summary and analysis. I appreciate that you have written strengths and limitations.
UTI is the most common post kidney transplant infection with incidence 10-98%.
The wide variation of UTI incidence due to inconsistent definition, diagnostic criteria used in studies & variable antibiotic prophylactic.
AST/IDCP 2019 guidelines define different condition: asymptomatic bacteriuria( no urine or systemic symptoms of infection), acute simple cystitis, acute pyelonephritis/complicated UTI & recurrent UTI(3 or more episodes of UTI in previous 2 months).
Classical manifestation of UTI usually absent due to use of immunosuppression & surgical denervation of transplanted kidney & ureter.
Gram negative rods asr the most causative micro-organism of UTI in kidney transplant & non transplanted patients.
MDR bacteria is commonly prevalent & problematic in Australiasia region.
Post operative factors: include intra-operative( deceased donor, ureteric stent & prolonged indwelling urinary catheterization) & post operative factors(acute dysfunction or rejection, & excessive immunosuppression).
Use of prophylactic of PCP(TMP-SMX) for 6 months associated with increased prevalence of drug resistance.
Post transplant UTI increase morbidity & hospitalization rate & acute graft dysfunction.
Aim of the study:
Identification of risk factors & prevalence of post transplant UTI & assessment of UTI effect on renal function during UTI episodes.
Methods:
Retrospective observational study
Included patients are all adult with kidney & simultaneous kidney & pancreas transplantation from first July 2011-July first 2016 & returned for post transplant care for 2 years.
UTI defined as presence of bacteria on lab test & recipients use one or more of antibiotics.
Asymptomatic bacteriuria treated only if there was unexplained rise in serum creatinine.
The patted divided into 2 groups according presence or absence of UTI.
UTI included from 1 month post transplant up to 2 years post transplantation.
Result & discussion:
Incidence of UTI was 27.8%.
The only risk factors reach statistical significance on adjusted analysis were female & age., while pre-existing UTI or urogenital abnormalities found to be not a risk factors.
Study on 2016 found that early(1 week) removal of ureteric stent associated with lower risk of UTI compared to late(4 weeks) removal.
Very low rate of UTI or bacteriuria caused by ESBL-producing organism.
TMP-SMX as CPC prophylaxis didn’t protect against UTI in patients of this study.
No difference of baseline serum creatinine in subgroups who use TMP-SMX.
UTI affect renal function acutely during episode but didn’t affect renal function 2 years post transplant.
Complicated UTI didn’t affect renal function at 2 years post transplant.
Time-point 2 years post transplantation uses because:
Well documented increased risk of UTI in first 12 month post transplantation.
2 years represent a reliable & accessible database of dispensing & medical record accuracy.
No clear evidence of prophylaxis effectiveness in patients with recurrence UTI.
Limitations of the study:
Retrospective study.
Small size sample & limited follow-up time.
Difficult to generalize on patient long-term graft function using 2 years post transplantation.
Included of all clinical significant asymptomatic bacteriuria, cystitis & transplant pyelonephritis.
Hi Dr Ban, What is your reason for allocating level 3 to this report? I like your summary and analysis. I appreciate that you have written strengths and limitations.
Article -5 Q1. Introduction
· Urinary tract infections (UTI) are the most prevalent infections following kidney transplantation (KT)
· Incidence is in the range of 10 to 98% probably due to lack of standardized definition
· Routine urine dipstick in transplant outpatients contributed to early diagnosis of asymptomatic bacteriuria
· The common organisms are gram negative rods such as E. coli. Other organisms include K.pneumonia, P.aeruginosa and Enterococci species.
· The number of multi-drug resistant gram negative are also increasing worldwide
· UTI may be associated with increased morbidity and risk of allograft dysfunction
· The objective of this study was to look at the prevalence, risk factors, impact of the allograft function at 2 years, the type of the organism, antibiotic treatment, and the protective effect of trimethoprim/sulfamethoxazole (TMP/SMX)
· UTI was defined as bacteriuria and exposure to one or more antibiotics course Methodology
· Retrospective analysis carried out at the Royal Brisbane & Women Hospital (RBWH)
· From July 2011 to July 2016
· They included 72 kidney transplant recipients
· The medical records of the patients were reviewed in details including treatment history and any episode of UTI 2 years after transplantation
· Patients were divided into two groups based on the presence or absence of UTI
· Those whose required hospital admission because of UTI were categorized as complicated UTI or pyelonephritis Results
· Around 20 patients suffered from at least one attack of UTI
· Risk factors for UTI after adjusted statistics were female gender and age
· There was 14% elevation in serum creatinine following an episode of UTI and 9% decreased in creatinine after treatment of UTI
· Up to 82% of UTIs were caused by E. Coli and Klebsiella pneumoniae
· Two-third of the UTI responded well to a single dose antimicrobial therapy
· The order of the antibiotics used for treatment of UTIs was penicillin in 49% of cases followed by cephalosporin in 36% of cases
· The use of TMP/SMX did not protect against development of UTI Limitations
· Retrospective
· Small sample size
· Limited follow up period Strength
· They included all spectrum of UTI across renal transplantation Conclusion
· Female gender, age were the most important risk factors for UTI and E. Coli was the most common organism. All patients with or without history of UTI had normal allograft function at two years
Q.2
· Retrospect, observational study level 3
Hi Dr Ben, What is your reason for allocating level 3 to this report? I like your summary and analysis. I appreciate that you have written strengths and limitations.
Following successful kidney transplantation, one of the most feared infections is urinary tract infection as it can be accompanied by a prolonged hospital stay and sometimes allograft rejection or impaired recipient survival if severe. UTI in kidney transplantation has a wide incidence rate of 10%-98% partly due to various definitions used for the infection.
Definition of UTI according to the 2019 American Society of Transplantation Infectious Disease Community of Practise
asymptomatic bacteriuria
acute simple cystitis
acute pyelonephritis (complicated UTI)
recurrent UTI
The most commonly implicated organism both in kidney transplant and non-kidney transplant patients is E.coli, while others are Klebsiella pneumonia, Pseudomonas aeruginous, and enterococci species. Of note is the increasing global rate of multidrug resistance against many of the available antibiotics
Risk factors for the development of UTI
a) Preoperative factor: female sex, DM, urological abnormality
b) Intraoperative factor: diseased donor, DJ stent, prolong urethral catheter
c) Postoperative: acute allograft rejection, excessive immunosuppressive drug use
Aim of the study
to identify risk factors and prevalence of KTP UTI
to assess if UTI affects allograft function after 2 years
to identify the common organism causing UTIs and data on antibiotics used and resistance to them
Method
It is a retrospective study between 1st July 2011 to 1st July 2016
those outside the time frame were excluded from the study
patient were divided into two groups, those with and without UTI
The definition used for UTI in the study was UTI as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
Results and Discussion
The sample size was 72 transplant patients with 55 receiving diseased organs, 10 simultaneous kidneys and pancreas transplants, and 7 living donations.
The median age is 47 years (17-71years)
The induction therapy was basiliximab (received by 66 recipientsyceam), and thyroglobulin (received by 3 recipients) along with TAC, and MMF
The incidence rate of UTI in the study is 27.8%
E.coli is the most isolated organism
Most recipients were treated with one antibiotics and the commonly used was penicillin
On univariate analysis, female gender, hyperglycemia, and acute rejection were the risk factor for the UTI
On adjusted analysis, female gender and age were the risk factors
Trimethoprim usage for PJP did not confer protection against UTIs, despite 93% of patients using this treatment at doses considered prophylactic for UTIs
Acutely affected renal function was observed to approach baseline within two-weeks after treatment.
UTI did not impaired kidney function at 2 years of the study
Limitation of the study
small sample size
study design is retrospective
short follow up time
Strength of the study
Use of all emcompassing definition of UTI
Conclusion
Urinary tract infection is the most common infection after kidney transplantation, and common risk factor like female sex, age, and hyperglycemia are common. The used of TMX as prophylaxis appears not to play any significant role in reducing the incidence of UTIs among kidney transplantation patients
Hi Dr Abiola,
What is your reason for allocating level 3 to this report? I like your summary and analysis. I appreciate that you have written strengths and limitations.
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics.
Risk factors for the development of a post-transplant
UTI can be divided into pre-operative (host) factors, intra-operative factors and post-operative factors. Preoperative factors include female sex, diabetes mellitus and the presence of urological abnormalities.
The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
We aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode. Then we assessed if UTI resulted in declining allograft function at 2 years post-transplant.
We had very low rates of UTI or bacteremia caused by
ESBL-producing organisms and none of our patients died as a result of UTI. Nevertheless, there is a known association between mortality and bacteremia secondary to MDR gram negative infections in transplant recipients and MDR infections are expected to become more problematic in the future
In this study, UTIs acutely affected renal function during an episode, with renal function approaching baseline from 2 weeks post UTI. Importantly, UTIs did not impair overall renal function at 2 years post-transplant.
Many of the reported risk factors for UTIs in this population, such as gender and age, cannot be mitigated. Moreover, vigilance and monitoring for hyperglycaemia in the transplant population is important for cardiovascular benefits aside from hyperglycaemia being a predictor of increased UTI risk.
It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data, but the results are nevertheless indicative of important trends.
In conclusion, our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
Please summarise this article.
# The aim:
*To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode.
Utilisation rates of TMP/SMX prophylaxis were also investigated.
# Introduction:
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%.
*The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics.
*Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases
Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurrent UTI.
*Risk factors for the development of a post-transplant
UTI can be divided into pre-operative factors, intra-operative factors and post-operative factors.
*The 2009 (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.
# Methods:
*This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital. Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were captured.
*Baseline demographics were collected for all adult patients (> 18 years old)
who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July
1st 2011 to July 1st 2016.
*The study included all adult patients returning to centre who had their post-transplant care with us for 2 years from their renal transplant date and within the above specified timeframe.
*The study excluded those patients returning to centre within the above timeframe but not completing their 2 years of post-transplant care with us, as well as those who received their transplant outside the specified timeframe.
# Results:
* Of these patients, 20 (27.8%) had at least one UTI.
* Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis.
* Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on
adjusted analysis.
* On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode,
which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance. (p = 0.076).
* Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment.
*Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
* The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
# The limitation of the study:
*Itts retrospective nature, small sample size and relatively limited follow-up.
*It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data. *UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
# Conclusion:
The results are valid for a similar closely monitored low immunosuppression transplant cohort and study findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
# The level of evidence is level 2
Summary
Retrospective study – at the Royal Brisbane and Women’s Hospital, 72 renal transplant recipients with 5-year follow up are presented here.
Patients’ charts, pathology records and dispensing histories were reviewed.
All UTIs from 2 years post transplantation were noted.
The prevalence, risk factors for post-transplant UTIs was identified; its effects on renal function during and after 2 years post-transplant was observed.
In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis were also quantified.
Results
Out of 72 renal transplant patients – 55 were deceased donor, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants.
Of these patients, 20 (27.8%) had at least one UTI episode.
Old age, female sex, anatomic abnormality, hyper-glycemia, acute rejection episodes were the risk factors for developing UTI.
Common organisms – Escherichia coli and Klebsiella pneumoniae accounted for 82% of UTI episodes.
70% of UTI cases required only single course of antibiotic treatment – either penicillin (49%) or cephalosporin (36%) was used in the majority of cases.
Use of TMP/SMX for PCP prophylaxis did not reduce UTI rate – (90% of the cohort using this).
There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI.
Also, no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort noted.
None of patients died as a result of UTI.
UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI.
Discussion
The incidence of UTIs in a renal transplant was 27.8%
Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared to removal at 4 weeks.
There is association between mortality and bacteremia secondary to MDR Gram- negative infection.
Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function.
Limitations:
A retrospective nature
Small sample size
All cases of UTI – asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included
Level of evidence : Level 2 (retrospective observational study)
●(UTI) are the most common of infections after renal transplantation
• asymptomatic bacteriuria,
• acute simple cystitis (lower UTI),
• acute pyelonephritis (complicated UTI),
• and recurrent UTI
●The‘classical’ symptoms of UTI, are often absent in the renal transplant population
● UTI in a renal transplant recipient may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
●A urine dipstick test is routine practice allowing for the early detection of asymptomatic bacteriuria
● Gram-negative rods are the main pathogens
Escherichia coli is the most common uropathogen
Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species
● (MDR) gram negative bacteria, is most problematic in the Australasian region
MDR bacteria such as (ESBL) producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae
Risk factors for the development of a post-transplant UTI can be divided into
• pre-operative (host) factors,
• intra-operative factors
• and post-operative factors.
Preoperative factors
• female sex,
• DM
• urological abnormalities.
Intraoperative factors
• deceased donor,
• ureteric stents
• prolonged indwelling bladder catheterisation.
Postoperative factors
• acute allograft dysfunction and rejection
• as well as excessive immunosuppression as a result of rejection episodes
●The 2009 (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
A recent study of over 60,000 renal transplant recipients from 2000 to 2011 from the United States Renal Data System registry for infections in the first 12 months post-transplantation demonstrated that 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
We aimed to identify
the prevalence and risk factors for post-transplant UTIs
and assess UTIs’ effect on renal function during a UTI episode.
The declining allograft function at 2years post-transplant.
Methods
● A retrospective observational study was conducted at the (RBWH),
(>18 years old) who received a renal transplant and whose post-acute transplant follow-up was from July 1st 2011 to July 1st 2016.
●This study was approved by the Royal Brisbane and Women’s Hospital Human Research Ethics Committee
●72 patients in total
●Induction therapy consisted of either intravenous basiliximab or ATG and methylprednisolone, together with tacrolimus and mycophenolate.
Results
●There was no association with UTI for those that received thymoglobulin induction (p=0.20).
●the mean number of UTIs per person was 3.85.
● 33.8% of the UTI episodes were classified as a complicated pyelonephritis).
● ESBL-producing organism in 3.9% of urine cultures
●TMP/SMX prophylaxis at a dose of 400/80mg/day was almost universal
●there was no significant change in serum creatinine and (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
Or between those with a complicated UTI/pyelonephritis versus those with a simple UTI (p=0.331).
Discussion
●Our study highlights the incidence of UTIs in a renal transplant population with 27.8%
Female gender and age were the only risk factors that reached statistical significance.
●Many studies have revealed an association between stent usage and higher rates of UTI
● trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs.
●UTIs did not impair overall renal function at 2 years post-transplant.
● Some cohort studies have demonstrated higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%.
●Furthermore, in other studies severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
Why The time-point of 2 years post-transplant was chosen ?
●●Firstly, increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial three to 6 months.
●●Secondly, 2 years represented a reliable and accessible dataset.
● What is not clear from this study is the manner in which monitoring and surveillance of UTIs should occur
●What is also not clear from this study is the effectiveness of prophylactic antibiotics in those patients with frequent or recurrent UTIs
●Our study highlights that UTIs are very common.
● Risk factors were in line with other published studies with female gender, older age and hyperglycaemia conferring risk.
●UTIs did not affect renal function at 2 years post-transplant, and despite 93% of our patients taking TMX-SMX prophylaxis, the trimethoprim component seemed not to confer protection against UTIs.
●ESBL organisms causing UTIs were relatively uncommon at 3.8%.
The limitations in this study design,
○ retrospective nature,
○ small sample size
○ relatively limited followup
●It is difficult to generalise on patients’ long-term allograft function using 2 year post-transplant data
● an allencompassing UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis
● the evidence does not support treating asymptomatic bacteriuria, however many clinicians would treat if it is accompanied by an unexplained rise in serum creatinine.
In conclusion,
our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
Level II
Summary
Introduction
This article is surrounding urinary tract infections in renal transplant recipients. UTIs are one of the most common infections post transplant. UTIs can cause increased morbidity and mortality in the transplant population and has been widely cited as a fatal infection if not treated. In addition, UTI has the potential to cause acute dysfunction of the allograft and also increase hospitalization rates in transplant recipients. Long term survival of graft may be impaired, although further studies are needed to confirm this.
Discussion
This study analyzed the prevalence, risk factors, and effect on renal function that UTIs have post transplant.
Risk factors includes female gender, increasing age and usage of stent. However, early removal of tent within 1 week has found to be associated with lower incidence of UTIs in this patient sector. Previous history of UTI has not been found to increase risk of post transplant UTI.
TMP may not be highly effective as prophylaxis against UTI since a large number of patients develop infection despite prophylaxis. In addition, TMP can cause a reversible increase in serum creatinine due to inhibition of the tubular secretion of creatinine.
The study found that while UTI had an acute effect on graft function, it did not adversely impact graft function in the near future. Early detection and aggressive treatment may be a contributing factor to this outcome. This can also protect graft function at 2 years post transplant, which is the most common period for complicated and possibly fatal UTI.
This study does not encourage treatment of asymptomatic bacteriuria, however, if this is accompanied with unexplained rise in serum creatinine, then treatment can be considered.
Conclusion
Aggressive treatment, early detection and low immunosuppression play a key role in treating UTI and protecting allograft function in the long and short term.
Level of evidence
level of evidence is 2.
Summary
This was a retrospective analysis of 72 kidney transplant patients treated at the Royal Brisbane and Women’s Hospital during a 5-year period.
To determine the prevalence and risk factors for post-transplant UTIs and to evaluate the impact of UTIs on renal function both during and after 2 years post-transplant by UTI episode, patient charts, pathology records, and dispensing histories were reviewed. All UTIs occurring from 2 years after transplantation were reported.
Additionally, the kind of antibacterial medicine used for each episode of a UTI, as well as the usage of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis, were measured.
Result
72 individuals underwent kidney transplants; of them, 55 were from deceased donors, 7 from live relatives, and 10 underwent combined kidney and pancreas transplants.
20 (27.8%) of these individuals had at least one UTI.
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
82% of UTI episodes were caused by common microorganisms (Klebsiella pneumoniae and Escherichia coli).
Between individuals with and without a UTI, there was no discernible difference in serum creatinine and estimated glomerular rate (eGFR) from baseline to two years after the transplant.
Additionally, there was no statistically significant difference between those who had a difficult UTI/pyelonephritis and those who had a simple UTI or the remainder of the group in the change in serum creatinine from baseline to 2 years after the transplant.
None of the individuals experienced fatal UTI.
Renal function was impacted by UTIs during an episode, returning to baseline 2 weeks after the UTI.
Discussion
Discussion
In a kidney transplant, the prevalence of UTIs was 27.8%.
In comparison to removal at 4 weeks, early ureteric stent removal at 1 week was linked to a reduced risk of UTIs.
Bacteremia brought on by MDR gram negative infection is associated with death.
Long-term renal function may be negatively impacted by severe UTIs and urosepsis.
Limitations:
an ahistorical nature
a modest sample size
Cystitis, transplant pyelonephritis, and all asymptomatic bacteriuric UTI patients were included.
it is retrospective observational study level 2
Summary
This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital.
Patient charts, pathology records and dispensing histories were reviewed and all UTIs from 2 years post transplantation were noted to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during and after 2 years post-transplant by UTI episode.
In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
Results
Out of 72 renal transplant patients, 55 were deceased donor, 7 were living related kidney transplants and 10 were simultaneous kidney pancreas transplants.
Of these patients, 20 (27.8%) had at least one UTI
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes.
70% of UTI cases require only a single course of antibiotic treatment.
Antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI.
There was also no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort.
None of patients died as a result of UTI.
UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI.
Discussion
The incidence of UTIs in a renal transplant was 27.8%
Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with removal at 4 weeks.
There is association between mortality and bacteremia secondary to MDR gram negative infection.
Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function.
Limitations:
A retrospective nature
Small sample size
All cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included
Level of evidence for retrospective observational study is Level: 2
Urinary tract infections (UTIs) are a common complication after renal transplantation, with estimated incidences varying widely due to inconsistencies in definitions and diagnostic criteria across studies. The American Society of Transplantation Infectious Diseases Community of Practice has attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI. The symptoms of UTI in renal transplant recipients may be atypical due to immunosuppression and surgical denervation of the transplanted kidney and ureters. Risk factors for post-transplant UTI include pre-operative factors, intra-operative factors, and post-operative factors. UTIs in this population can result in increased morbidity and hospitalization rates, acute allograft dysfunction, and even an increased risk of death. The prevalence and risk factors for post-transplant UTIs were investigated in a retrospective observational study conducted at a quaternary level hospital in Brisbane, Australia.
The study aimed to assess the effect of UTIs on renal function during a UTI episode and to determine if UTI resulted in declining allograft function at 2 years post-transplant. The study also collected data on causative organisms and antibiotics used. Statistical analysis was performed to identify associations between variables.
RESULTS
In a 5-year study of 72 first-time renal transplant patients, 27.8% experienced at least one UTI, with a mean of 3.85 UTIs per person in the UTI sub-group. Univariate analysis showed older age, female gender, hyperglycemia, and acute rejection episodes as risk factors for UTI, but only female gender and age remained statistically significant in adjusted analysis. UTI episodes led to a significant increase in serum creatinine levels, but there was no significant change in serum creatinine or eGFR up to 2 years post-transplant between patients with or without UTIs. Complicated and simple UTIs did not differ significantly in their effect on serum creatinine levels.
DISCUSSION
This study examined UTIs in renal transplant patients, finding a 27.8% incidence rate, with female gender and age as statistically significant risk factors. Surprisingly, pre-existing history of UTI or urogenital abnormality were not risk factors. The study observed low rates of UTI or bacteremia caused by ESBL-producing organisms and no UTI-related deaths. Trimethoprim usage for Pneumocystis prophylaxis did not seem to protect against UTIs, raising questions about its effectiveness in UTI prophylaxis for kidney transplant patients. UTIs acutely affected renal function, but did not impair overall renal function at 2 years post-transplant. The study’s limitations include its retrospective nature, small sample size, and relatively limited follow-up. Despite these limitations, the results offer an interesting perspective on UTI risk factors, treatment, and the concept of antibiotic prophylaxis for UTIs in renal transplant patients. The findings are valid for similar closely monitored low immunosuppression transplant cohorts.
UTI- commonest post renal transplant infections ranging between 10 and 98%. The cause of discrepancy is attributed mainly to the availability of the diagnostic tools and prophylactic measures.
After long practice finally the last updates by the AST Infectious Diseases Community of Practice 2019 guidelines managed to establish clear definitions for all UTI syndromes particularly: asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis and recurrent UTI.
Common ‘classical’ symptoms of UTI in the form of urinary frequency, dysuria, urgency, or suprapubic pain, mostly don’t exist owing to the combination of IS and surgical denervation of the transplanted kidney and ureters. Thus, the presentation may be vague as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine, highlighting the routine outpatient dipstick testing is mandatory.
The most common organism encountered is Escherichia coli followed by other common enteric organisms as Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.
Risk factors
UTIs in this population poses the patients to the risk of increased morbidity, hospitalisation rates besides acute allograft dysfunction.
The question then is does it affect long-term allograft function or reduce allograft or patient survival.
A study conducted by the USRDS registry for infections for more than 60,000 renal transplant recipients from 2000 to 2011 in the first year post renal transplantation concluded that 32% of patients had a UTI in the first year which was associated with a 41% increased relative risk of death.
This retrospective observational study performed at the Royal Brisbane and Women’s Hospital (RBWH) for 2 years duration post renal transplantation.
The study population involved all adult renal transplant recipients (> 18 years old even simultaneous kidney-pancreas transplantation) as well as those having their post-acute transplant follow-up at RBWH from July 1st 2011 to July 1st 2016.
UTI is defined by the existence of bacteriuria proved by laboratory reports and receipt of one or more courses of antibiotics. Importantly, three consecutive sera creatinine were needed; ‘Pre-UTI’ was within 3 months before the episode, the ‘UTI episode’ within 2 weeks of recorded bacteriuria and ‘post UTI’ by 15 days to 3 months post UTI.
All UTI episodes were included from 1 month post renal transplantation up to 2 years. Severity was classified by the presence of simple cystitis or by complicated UTI/pyelonephritis requiring hospital admission for parenteral antibiotic therapy.
A total number of 72 patients (55 deceased donor transplants, 7 LRRT and 10 simultaneous kidney pancreas transplants) were first renal transplant.
There were no association between the occurrence of UTI and induction therapy even those who received thymoglobulin induction which were only 3 patients (p = 0.20).
The mean age at transplantation was 45.5 years (median: 47, range: 17–71). All patients removed catheter 3–5 days post transplantation. Also, ureteric stents were removed 4–6 weeks post operatively.
In this study, 20 patients had at least one UTI over the study period with incidence rate for a UTI was 27.8%. The mean number of UTIs per person among all patients was 3.85.
About 55% of the patients (11/20) in the UTI subgroup had at least one episode of complicated UTI/pyelonephritis.
The other group 45% (9/20) had at least one simple UTI episode. Total of 33.8% of the UTI episodes were considered complicated UTI/pyelonephritis (26/77).
It was found that only 8% (6/77) of blood cultures obtained at time of a UTI episode were positive.
ESBL-producing organism in 3.9% of urine cultures (3/77) was the most common. It had the feature of response to penicillin, gentamicin and carabepenem.
The study also confirmed that older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) are still considerable risk factors for developing UTI.
However, HLA mismatches and strong pre-existing history of UTIs were not found to be risk factors anymore.
Each UTI episode was associated with a mean increase in serum creatinine of 21 micromol/L (14.4%, SEM 5.20) and statistically significant (p = 0.027).
While after resolution of the UTI, the estimated mean reduction was 16 micromol/L (9.1%, SEM 6.23) reduction in serum creatinine with statistical significance (p = 0.076).
There was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between both groups with complicated UTI/pyelonephritis and simple UTI (p = 0.331) or even the rest of the whole cohort (p = 0.814).
The high incidence of post renal transplant UTI about 27.8% was like other studies. Concerning the known risk factors for developing a UTI as other studies only female gender and age were the only significant risk factors while pre-existing history of UTI or urogenital abnormality are no more considered risk factors.
In 2016, a study elaborated that early removal of ureteric stents at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks while our study found that they were not linked at all.
The study proved low rates of ESBL-producing organisms UTI or bacteraemia besides no deaths were encountered due to UTI.
The use of trimethoprim for Pneumocystis prophylaxis was not associated with more protection against UTIs in our patients even when being used by 93% of patients at doses considered prophylactic for UTIs.
Among all groups, no significant difference in baseline serum creatinine levels was demonstrated.
Limitations were mainly being retrospective with small sample size and relatively limited follow up duration. In order to assess the patients’ long-term allograft function 2-year study duration is definitely not satisfactory.
Strengths were the wide application of the definition of UTI in all cases.
Level of evidence is II.
V. Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Summarise this article
Background
– UTIs are the most common infections post kidney transplant, estimated incidence is 10-98%
– UTIs are associated with increased morbidity, hospitalization rates and acute graft dysfunction
– UTIs impair graft and patient survival
– definitions/ classification of ASB and UTI in KTRs:
· asymptomatic bacteriuria (ASB): no urinary or systemic symptoms of infection
· acute simple cystitis (lower UTI): dysuria, urgency, frequency or suprapubic pain but no systemic symptoms, no ureteral stent, nephrostomy tubes, chronic urinary catheter
· acute pyelonephritis (complicated UTI): fever, chills, malaise, hemodynamic instability, leukocytosis (with no other apparent etiology), flank/ graft pain, bacteremia with same organism as in urine, dysuria, urgency, frequency, suprapubic pain may or may not be present
· recurrent UTI: ≥3 UTIs in prior 12-month period
– the classical symptoms of UTI i.e., frequency, dysuria, urgency, suprapubic pain, are often absent in KTRs due to immunosuppression and surgical denervation of the transplanted kidney and ureters
– therefore, UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine
– routine urine dipstick test allows for early detection of ASB in KTRs
– gram negative rods are the main cause of UTIs in both the transplant and the non-transplant population i.e., E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterococci
– there is a notable increase in pathogenic MDR gram-negative bacteria e.g., ESBL producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae which require use of the much older antibiotics which could be nephrotoxic
– Risk factors for development of posttransplant UTI:
· Pre-operative (host) factors: – female sex, diabetes, presence of urological abnormalities
· Intra-operative factors: – DDKT, use of ureteric stents, prolonged indwelling urethral catheter
· Post-operative factors: – acute graft dysfunction, rejection, excessive immunosuppression secondary to rejection episodes
– KDIGO 2019 recommends TMP-SMX for PCP prophylaxis for at least 6 months posttransplant
– however, there are studies showing a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis
– UTIs in KTRs are associated with increased morbidity and hospitalization rates, acute graft dysfunction
– since most studies are retrospective, it is not clear whether UTIs impair long-term graft function or reduce graft or patient survival
Methods
– retrospective observational study, 72 KTRs, 5-year period
– patient’s charts, pathology records and antibiotic dispensing records were reviewed
– all UTIs 2 years posttransplant were captured
– Aim:
· to determine the prevalence and risk factors for posttransplant UTIs
· to assess the effect of UTIs on kidney function during a UTI episode
· to assess if UTIs result in declining graft function at 2 years posttransplant
· to document the causative agent, class of antibiotics used for each UTI episode, number of different antibiotics used per episode, utilization rates of TMP-SMX prophylaxis
– UTI was defined as presence of bacteriuria on laboratory reports and use of one or more courses of antibiotics
– this definition therefore included all cases of acute simple cystitis, transplant pyelonephritis and ASB if treated with antibiotics
– ASB was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary to use antibiotics three consecutive sera creatinine were reviewed i.e., “pre-UTI” (within 3 months prior to the UTI episode), “UTI episode” (within 2 weeks of a recorded bacteriuria) and “post-UTI” (15 days to 3 months post a UTI episode)
– patients were stratified into presence or absence of at least one UTI episode, those with a UTI episode were subclassified into uncomplicated (simple cystitis) vs complicated UTI (pyelonephritis, systemic symptoms requiring hospital admission for parenteral antibiotics)
Results
– 72 patients were reviewed, 55 DDKT, 7 LDKT, 10 simultaneous kidney and pancreas transplants
– induction therapy: Basiliximab or ATG and methylprednisolone, together with tacrolimus and mycophenolate
– there was no association between ATG use and UTIs
– maintenance therapy: tacrolimus, mycophenolate, prednisone
– tacrolimus trough level target: 5ng/ml for intermediate immunologic risk patients and 6-7ng/mL for those with a high immunologic risk
– mean age at transplantation was 45.5 years
– indwelling urine catheter was removed 3-5 days posttransplant
– ureteric stent was routinely removed 4-6 weeks posttransplant unless patients developed early UTI in which case it would be removed earlier
– 27.8% (20 patients) had at least one UTI
– in the UTI sub-group, 77 UTI episodes were analysed, mean number of UTI episodes per person was 3.85, 55% of the patients had at least one episode of complicated UTI while 45% had simple UTI, 33% of the UTI episodes were complicated UTI/ pyelonephritis, ESBL-producing organism (E. coli) was isolated in 3.9% of the urine cultures
– E. coli and Klebsiella pneumonia accounted for 82% of the UTI episodes
– 70% of the UTI cases responded to a single course of antibiotics
– antibiotics commonly used were either a penicillin (49%) or cephalosporin (36%)
– 93% of the patients were on TMP-SMX prophylaxis
– use of TMP-SMX prophylaxis for PCP prophylaxis did not influence the rate of UTI
– risk factors for developing UTI: older age, female sex, hyperglycemia, acute rejection episodes
– there was an increase in serum creatinine (21micromol/L) during a UTI episode with a notable decline in serum creatinine (16micromol/L) after the UTI episode
– there was no significant difference in serum creatinine and eGFR from baseline to 2 years posttransplant
Discussion
– UTI is the most common infection following kidney transplant
– risk factors for UTI: female sex, age, hyperglycemia
– there is an association between stent usage and higher rates of UTI
– there is a relationship between mortality and bacteremia secondary to MDR gram negative infections in KTRs
– TMP-SMX use for PCP prophylaxis does not confer protection against UTIs
– UTIs acutely affects kidney function but does not impair overall kidney function at 2 years posttransplant
– ESBL organisms causing UTI were uncommon
Study limitations
– retrospective study
– small sample size
– limited follow up
Conclusion
– there was no significant change in serum creatinine and eGFR from baseline to 2 years posttransplant between those with or without a UTI episode
Level of evidence provided by this article?
– Level II
◇ Background
● Urinary tract infections (UTI) are the most common of infections after renal transplantation with incidence 10 – 98%
● Definitions UTI syndromes including:
☆ Asymptomatic bacteriuria: No urinary or systemic symptoms of infection
☆ Acute simple cystitis (lower UTI): Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/
nephrostomy tube/chronic urinary catheter
☆ Acute pyelonephritis (complicated UTI)
Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency, frequency, suprapubic pain may or may not be present
☆ Recurrent UTI
≥3 UTIs in prior 12 month period
● The ‘classical’ symptoms of UTI are often absent in the renal transplant
● UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
● Escherichia coli is the most common uropathogen
● Risk factors for UTI divided into :
☆ pre-operative (host) factors:
* Female sex
* Diabetes mellitus
* Presence of urological abnormalities.
☆ Intra-operative factors :
* A deceased donor
* Use of ureteric stents
* Prolonged indwelling bladder catheterisation
☆ Post-operative factors :
* Acute allograft dysfunction
* Rejection
* Excessive immunosuppression as a result of rejection episodes
● It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival
● 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
◇ Methods
☆ A retrospective observational study
☆ All adult patients (> 18 years old) who received a renal transplant
☆ from July 1st 2011 to July 1st 2016.
☆ UTI is defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
☆ This included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
☆ Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
☆ To estimate renal function three sera creatinine were reviewed.
▪︎Pre-UTI: 3 months prior to an episode,
▪︎UTI episode: within 2 W of bacteriuria
▪︎post UTI: 15 D to 3 M post a UTI episode.
☆ Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
☆ All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
◇ Discussion
● The incidence of UTIs in a renal transplant was 27.8%
● Risk factors for developing a UTI, Female gender and age were the only risk factors reached statistical significance
● A pre-existing history of UTI or urogenital abnormality were not found to be a risk factors
● Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with stent removal at 4 weeks
● Very low rates of UTI or bacteremia caused by ESBL-producing organisms
● None of patients died as a result of UTI.
● There is association between mortality and bacteremia secondary to MDR gram
● Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in patients
● Trimethoprim causes a reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine
● UTIs affected renal function during an episode, with renal function approaching baseline 2 weeks post UTI.
● UTIs did not impair overall renal function at 2 years post-transplant.
● Higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%
● Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
● Hyperglycaemia being a predictor of increased UTI risk.
● ESBL organisms causing UTIs were relatively uncommon at 3.8%.
● Limitations:
☆ A retrospective nature
☆ Small sample size
☆ Relatively limited followup.
☆ Study encompassing all cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis Although evidence does not support treating asymptomatic bacteriuria
☆ The manner in which monitoring and surveillance of UTIs should occur is not clear
☆ The effectiveness of prophylactic antibiotics in those patients is not clear
● Level : 2
Introduction:
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilization rates of prophylactic antibiotics.
the diagnosis of UTI among renal transplant recipients has been fraught by such inconsistencies up until now.
Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant populations . Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.
Risk factors for posttransplant UTI:
1. Preoperative: female sex, diabetes mellitus and the presence of urological abnormalities.
2. Intraoperative: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization
3. Postoperative. acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes.
UTIs in this population are serious with increased morbidity and hospitalization rates, as well as acute allograft dysfunction
Methods:
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period. Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July 1st 2011 to July 1st 2016.
For the purpose of this study, we defined UTI as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
Results:
Over a 5 year period, 72 patients were reviewed posttransplant. over this time
there were 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants. All 72 patients include in this study had received their first renal transplant.
Induction therapy consisted of either intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate. 95.7% received intravenous basiliximab as their induction agent, with only 3 patients receiving thymoglobulin induction. There was no association with UTI for those that received thymoglobulin induction (p = 0.20). Patients were then maintained on a combination of tacrolimus, mycophenolate and prednisolone throughout the post-transplant period. Tacrolimus was dosed to target a trough of 5 ng/ml for patients with average immunological risk and 6–7 ng/ml for those with high immunological risk. Prednisolone was tapered to 6–7 mg / day wherever possible. Mycophenolate mofetil/sodium remained at 1 g twice daily/720 mg twice daily unless there was leucopenia, intolerable gastrointestinal side effects, a high risk of infections or a new malignancy, in which case it was reduced.
Conclusion:
Our study highlights the incidence of UTIs in a renal transplant population with 27.8% of this cohort experiencing a UTI. Similar rates have been demonstrated in other studies and support the notion that UTI remains the most common infection after renal transplantation.
The study identified risk factors for developing a UTI.
our results are valid for a similar closely monitored low immunosuppression transplant cohort and our findings offer an interesting perspective on the risk factor profile and treatment of UTIs as well as the concept of antibiotic prophylaxis for UTIs.
Level of evidence is II
Aim:
Identify the prevalence and risk factors and more understanding about post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode.
Retrospective study at quaternary hosital.
Inclusion criteria: Adults >18 yrs who received renal or renal pancreas transplant who followed up at RBWH;July 1st 2011 to July 1st 2016 for two years post Tx.
Results;
Total population 72, 27.8% had at least one UTI.
Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis. Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on adjusted analysis. On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode, which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance. (p = 0.076).
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment. Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
Limitations Retrospective study, single centre, small number, short FU
Level of evidence – 2
Summary
This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital.
Patient charts, pathology records and dispensing histories were reviewed and all UTIs from 2 years post transplantation were noted to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during and after 2 years post-transplant by UTI episode.
In addition to that the causative organism, the class of antibacterial drug employed for each UTI episode and use of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
Results
Out of 72 renal transplant patients, 55 were deceased donor, 7 were living related kidney transplants and 10 were simultaneous kidney pancreas transplants.
Of these patients, 20 (27.8%) had at least one UTI
Older age, female gender, hyperglycemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes.
70% of UTI cases require only a single course of antibiotic treatment.
Antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline to 2 years post-transplant between those with and without a UTI.
There was also no statistically significant difference in change in serum creatinine from baseline to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI or the rest of the whole cohort.
None of patients died as a result of UTI.
UTIs affected renal function during an episode, with renal function approaching baseline in 2 weeks post UTI.
Discussion
The incidence of UTIs in a renal transplant was 27.8%
Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with removal at 4 weeks.
There is association between mortality and bacteremia secondary to MDR gram negative infection.
Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function.
Limitations:
A retrospective nature
Small sample size
All cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis were included
Level of evidence for retrospective observational study is Level: 2
summary
· This study examined the prevalence and risk factors for post-transplant UTIs in 72 renal transplant patients at a quaternary care centre in Australia.
· Results showed that 20 (27.8%) had at least one UTI, with older age, female gender, hyperglycaemia, and acute rejection episodes being risk factors for developing a UTI.
· On average, there was a 14.4% increase in serum creatinine during a UTI episode, which was statistically significant.
· Urinary tract infections (UTI) are the most common of infections after renal transplantation, with an estimated incidence between 10 and 98%.
· However, the diagnosis of UTI among renal transplant recipients has been fraught by inconsistent definitions and diagnostic criteria.
· Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases have attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI.
· The ‘classical’ symptoms of UTI are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters.
· UTI can be divided into pre-operative (host) factors, intra-operative factors and post-operative factors, with pre-operative factors such as female sex, diabetes mellitus and urological abnormalities.
· The 2009 (KDIGO) guidelines recommend TMP/SMX for pre-prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.
· UTIs in this population are serious with increased morbidity and hospitalisation rates, as well as acute allograft dysfunction.
· in this study, UTI was defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
· All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
· Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
· Gender, type of transplant, type of kidney-pancreas (KP), pre-existing history of UTIs, pre-existing urinary tract abnormality, acute rejection episodes, hyperglycaemia, post-transplant diabetes, CMV viraemia, and TMP/SMX use were also examined.
· The ureteric stent was routinely removed 3-5 days after transplantation.
· 55% of the patients had at least one episode of complicated UTI/pyelonephritis, with 45% having at least one simple UTI episode.
· isolated an ESBL-producing organism in 3.9% of urine cultures and all three isolates were sensitive to penicillin, gentamicin and carabepenem initially, but one of the isolates has since become carbapenem-resistant.
· TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal in this cohort, with 85.7% of these patients using nitrofurantoin.
· Overall, there was no significant change in serum creatinine and (eGFR) from baseline out to 2 years post-transplant.
· There was no significant difference in baseline serum creatinine levels between the two subgroups as the vast majority of patients were on TMP-SMX prophylaxis.
· The time-point of 2 years was chosen as a reference point for a number of reasons, including the increased risk of UTIs in the initial 12 months and the high levels of immunosuppression employed in this period.
· level of evidence :
level 3 , a retrospective cohort study
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Study objective:
1) Prevalence of UTI
2) Risk factors for post-transplant UTI
3) The effects of UTI on renal function (during the episode) and 2 years post-transplant
Study design
Retrospective cohort study
Population
72 renal transplant recipients from a single centre
Results
1) Prevalence: 20/72 (27.8%) had at least one UTI
2) Risk factors: Older age, female, hyperglycaemia, acute rejection
3) Increased in serum creatinine during the episodes in 14.4% but no difference in 2 years follow up
4) Other analysis
Level 2 evidence
Q1- Please summarise this article.
Introduction:
Urinary tract infections (UTI) is the most common post renal transplant infections 10 and 98% according to different studies .
the American Society of Transplantation Infectious Diseases Community of Practice 2019 guidelines managed attempt to establish clear definitions for all UTI syndromes particularly:
– asymptomatic bacteriuria,
– acute simple cystitis (lower UTI),
– acute pyelonephritis (complicated UTI),
– recurrent UTI.
Classification of asymptomatic bacteriuria and UTI in renal transplant recipients [3]
Classification Description
Asymptomatic bacteriuria No urinary or systemic symptoms of infection
Acute simple cystitis Dysuria, urinary urgency/frequency, or suprapubic pain; but no
systemic symptoms and no ureteral stent/ nephrostomy
tube/chronic urinary catheter.
Acute pyelonephritis/ Fever, chills, malaise, haemodynamic instability, or leukocytosis
complicated UTI (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency,
frequency, suprapubic pain may or may not be present
Recurrent UTI ≥3 UTIs in prior 12 month period
Transplant patient UTI may not present with classical known signs and symptoms of frequency of micturition, dysuria, urgency or suprapubic pain, because of immunosuppression and surgical denervation of the transplanted kidney and ureters.
The patient may present with non-specific symptoms of new febrile illness, urosepsis or impaired graft function which raise the importance of routine outpatient dipstick testing.
The most common organism :
1- encountered is Escherichia coli ( most common) .
2- Klebsiella pneumonia.
3- Pseudomonas aeruginosa .
4- and Enterococci species.
Risk factors include :
1- female sex.
2- diabetes mellitus.
3- urological abnormalities.
4- use of ureteric stents and prolonged indwelling bladder catheterisation.
5- acute allograft dysfunction and rejection treated with heavy immunosuppression.
The presence of UTI increase the rate of morbidity, hospitalisation and acute allograft dysfunction.
According to large USA study this UTI is associated with41% increased relative risk of death.
Result :
72 patients were recruited- 55DCD, 7 LKD and 10 simultaneous kidney-pancreas transplant.
The induction therapy (basiliximab or ATG with methylprednisolone). With Maintenance therapy was triple therapy. All patients had an indwelling catheter . All patients had a ureteric stent.
20 out of 72 had a UTI with incidence rate of 27.8%.
11 out of 20 (58%) had a complicated UTI.
ESBL producing organism was isolated in 3.9%.
66out of 72 were on TMP/SMX prophylaxis.
Discussion:
UTI is the most common infection post transplantation.
Regarding the risk factors it revealed that
female gender and age are the only statistically significant risk factors for UTI .
data from one study report that early (1wk) stent removal is linked to lower UTI.
ESBL rate was low in this study. Trimethoprim used PJP is not protective against UTIs .
Acute UTIs may affect graft function in short term, but UTI has no effect on long term graft function. With each UTI attack there is an increase in serum creatinine level.
This Reported by Other studies demonstrating that severe UTIs and urosepsis producing negative impact on long-term graft function.
This study shows ineffectiveness of trimethoprim prophylaxis to prevent UTI.
The effective prophylactic program for UTI is needed to be determined .
Limitations;
– retrospective .
– small sample size .
– short follow up period .
Strength ;
– Involving all UTI definition
– involving asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
Q2- What is the level of evidence provided by this article?
Level of evidence 2
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Summarise;
Background.
Methods;
Inclusion criteria.
Exclusion criteria;
*UTI was grouped into pre UTI,UTI episode and Post UTI for the purposes of creatinine monitoring.
Results;
Discussion;
Limitations;
Level of evidence – Retrospective study – 2
This study by OLENSKI and colleagues aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
Additionally, the causative organism, the class of antibacterial drug employed for each UTI episode and utilisation rates of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
BACKGROUND
Urinary tract infections (UTI) are the most common of infections after renal transplantation with an estimated incidence between 10 and 98%.
Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant popula- tions [5]. Escherichia coli is the most common uropatho- gen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and En- terococci species. Furthermore, on a global scale there are increasing numbers of pathogenic multi-drug resist- ant (MDR) gram negative bacteria.
RISK FACTORS
Risk factors for the development of a post-transplant UTI can be divided into
pre-operative (host) factors
intra-operative factors and
post-operative factors.
Pre- operative factors include female sex, diabetes mellitus and the presence of urological abnormalities.
Intra- operative factors of note include kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterisation.
Post- operative factors of note include acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes
PROPHYLAXIS
The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommends TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant. More recent studies have shown a rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis yet the recommendation still stands
METHODS
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period. Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant (including simultaneous kidney-pancreas transplantation) and whose post-acute transplant follow-up was provided at RBWH from July 1st 2011 to July 1st 2016.
They included in this study all adult patients returning to their centre who had their post-transplant care with for 2 years from their renal transplant date and within the above specified time- frame.
They excluded those patients who did not complete 2 years of post transplant care.
Patients were stratified into two groups according to the presence or absence of at least one UTI episode. All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant. Theyfurther stratified the UTI sub-cohort for severity into those with simple cystitis versus those with complicated UTI/pyelo- nephritis.
RESULTS
Over a 5 year period, 72 patients were reviewed post- transplant.
There were 55 deceased donor transplants,
7 living related kidney transplants and
10 simultaneous kidney- pancreas transplants.
All 72 patients include in this study had received their first renal transplant.
20 patients experienced at least one UTI over the study period and the incidence rate for a UTI was 27.8% across the whole cohort.
Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis.
Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on adjusted analysis.
On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode, which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance.
(p = 0.076).
Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment. Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
CONCLUSION
There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those with and without a UTI.
LEVEL OF EVIDENCE 2
Introduction
Urinry tract infection (UTI) are the most common of infections after renal transplataion with an estimated incidence between 10 and 98%.
The wide variation can be attributed to various factors including inconsistent definitions and diagnostic criteria among studies as well as variable utilisation rates of prophylactic antibiotics .
The diagnosis of UTI among renal transplant recipients has been fraught by such inconsistencies up until now.
Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria , acute simple cystitis, acute pyelonephritis, and recurrent UTI.].
Objectives
We aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs ’ effect on renal function during a UTI episode.
We aimed to quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode
Methods
A retrospective observational study was conducted at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
This hospital receives transplanted patients for management in the early post-operative period.
Baseline demographics were collected for all adult patients (> 18 years old) who received a renal transplant and whose post-acute transplant follow-up was provided at RBWH from July.
For the purpose of this study, we defined UTI as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics
This allencompassing definition of UTI included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics
Results
Our centre receives transplant patients from other transplanting centres and over this time-frame there were 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidneypancreas transplants.
All 72 patients include in this study had received their first renal transplant.
Induction therapy consisted of either intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate.
69) received intravenous basiliximab as their induction agent, with only 3 patients receiving thymoglobulin induction.
There was no association with UTI for those that received thymoglobulin induction (p = 0.20).
Patients were maintained on a combination of tacrolimus, mycophenolate and prednisolone throughout the post-transplant period.
Tacrolimus was dosed to target a trough of 5 ng/ml for patients with average immunological risk and 6–7 ng/ml for those with high immunological risk.
Mycophenolate mofetil/sodium remained at 1 g twice daily/720 mg twice daily unless there was leucopenia, intolerable gastrointestinal sideeffects, a high risk of infections or a new malignancy, in which case it was reduced
Conclusion
Our study highlights the incidence of UTIs in a renal transplant population with 27.8% of this cohort experiencing a UTI .
Similar rates have been demonstrated in other studies and support the notion that UTI remains the most common infection after renal transplantation
This study is informative about UTIs in a carefully followed low immunosuppression transplant population and our observations are valid only for a similar population.
Female gender and age were the only risk factors that reached statistical significance on the adjusted analysis and surprisingly, a pre-existing history of UTI or urogenital abnormality were not found to be a risk factors on the unadjusted analysis.
Many studies have revealed an association between stent usage and higher rates of UTI.
A 2016 study demonstrated that early ureteric stent removal at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks.
Level of evidence is 2
Introduction:
-Urinary tract infections (UTI) are the most common of infections after renal transplantation.
-The consequences of UTIs in this population are serious, with increased morbidity and hospitalisation rates as well as acute allograft dysfunction.
-UTIs may impair overall graft and patient survival.
-Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumonia , Pseudomonas aeruginosa , and Enterococci species.
Risk Factors;
-Pre-operative (host) factors;
Include female sex, diabetes mellitus and the presence of urological abnormalities.
-Intra-operative factors;
Include kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization.
-Post-operative factors;
Include acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episode.
Aim;
-Identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
-Additionally, the causative organism, the class of antibacterial drug employed for each UTI episode and utilisation rates of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified.
Methodology:
-This was a retrospective study of 72 renal transplant patients over a 5-year period from (July 1st 2011 to July 1st 2016); who were managed at the Royal Brisbane and Women’s Hospital (RBWH), a quaternary level hospital in Brisbane, Australia.
-Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were captured.
Results:
-There were 72 renal transplant patients (had received their first renal transplant): 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants.
-Of these patients, 20 (27.8%) had at least one UTI; Older age , female gender , hyperglycaemia and acute rejection episodes were risk factors for developing a UTI on unadjusted analysis.
-Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment.
-Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
-The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment.
-There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
-There was also no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI.
-There was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus the rest of the whole cohort.
Discussion;
-Interestingly, a 2016 study demonstrated that early ureteric stent removal at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks.
-The time-point of 2 years post-transplant was chosen as a reference point for a number of reasons.
*Firstly, there is a well documented increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial three to 6 months, due to the surgical procedure itself and high levels of immunosuppression employed in this period.
*Secondly, from a pragmatic perspective, 2 years represented a reliable and accessible dataset in terms of dispensing and medical record accuracy.
Limitations;
-Its retrospective nature, small sample size and relatively limited follow-up.
-It is difficult to judge on patients’ long-term allograft function using 2 year post-transplant data.
-UTI definition which included all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis.
-Although evidence does not support treating asymptomatic bacteriuria in its own right, however many clinicians would treat if it is accompanied by an unexplained rise in serum creatinine.
Conclusions;
-There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those patients with and without a UTI.
-This is a retrospective observational study, with (LOE II)
◇ Background
● Urinary tract infections (UTI) are the most common of infections after renal transplantation with incidence 10 – 98%
● Definitions UTI syndromes including:
☆ Asymptomatic bacteriuria: No urinary or systemic symptoms of infection
☆ Acute simple cystitis (lower UTI): Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/
nephrostomy tube/chronic urinary catheter
☆ Acute pyelonephritis (complicated UTI)
Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain;
or bacteremia with same organism as in urineDysuria, urgency, frequency, suprapubic pain may or may not be present
☆ Recurrent UTI
≥3 UTIs in prior 12 month period
● The ‘classical’ symptoms of UTI are often absent in the renal transplant
● UTI in KTRs may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine.
● Escherichia coli is the most common uropathogen
● Risk factors for UTI divided into :
☆ pre-operative (host) factors:
* Female sex
* Diabetes mellitus
* Presence of urological abnormalities.
☆ Intra-operative factors :
* A deceased donor
* Use of ureteric stents
* Prolonged indwelling bladder catheterisation
☆ Post-operative factors :
* Acute allograft dysfunction
* Rejection
* Excessive immunosuppression as a result of rejection episodes
● It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival
● 32% of patients had a UTI in the first year and this was associated with a 41% increased relative risk of death
◇ Methods
☆ A retrospective observational study
☆ All adult patients (> 18 years old) who received a renal transplant
☆ from July 1st 2011 to July 1st 2016.
☆ UTI is defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
☆ This included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
☆ Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
☆ To estimate renal function three sera creatinine were reviewed.
▪︎Pre-UTI: 3 months prior to an episode,
▪︎UTI episode: within 2 W of bacteriuria
▪︎post UTI: 15 D to 3 M post a UTI episode.
☆ Patients were stratified into two groups according to the presence or absence of at least one UTI episode.
☆ All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
◇ Discussion
● The incidence of UTIs in a renal transplant was 27.8%
● Risk factors for developing a UTI, Female gender and age were the only risk factors reached statistical significance
● A pre-existing history of UTI or urogenital abnormality were not found to be a risk factors
● Early ureteric stent removal at 1 week was associated with lower rate of UTIs compared with stent removal at 4 weeks
● Very low rates of UTI or bacteremia caused by ESBL-producing organisms
● None of patients died as a result of UTI.
● There is association between mortality and bacteremia secondary to MDR gram
● Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in patients
● Trimethoprim causes a reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine
● UTIs affected renal function during an episode, with renal function approaching baseline 2 weeks post UTI.
● UTIs did not impair overall renal function at 2 years post-transplant.
● Higher rates of complicated UTI/pyelonephritis ranging from 13 to 24%
● Severe UTIs and urosepsis may indeed have an adverse impact on long-term renal function
● Hyperglycaemia being a predictor of increased UTI risk.
● ESBL organisms causing UTIs were relatively uncommon at 3.8%.
● Limitations:
☆ A retrospective nature
☆ Small sample size
☆ Relatively limited followup.
☆ Study encompassing all cases of UTI asymptomatic bacteriuria, cystitis and transplant pyelonephritis Although evidence does not support treating asymptomatic bacteriuria
☆ The manner in which monitoring and surveillance of UTIs should occur is not clear
☆ The effectiveness of prophylactic antibiotics in those patients is not clear
Level: 2
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
1. Please summarise this article.
2. What is the level of evidence provided by this article?
Please summarise this article
Introduction:
UTI is the most common infections post-transplant with variable incidence range 10-98%, this discrepancy due to different UTI definitions, diagnostic protocols, antibiotic prophylaxis used among studies and is associated with worse patients and graft survival.
UTI is defined as the presence of > 105 CFU in a proper urine sample (early morning sample, or from a sterile catheter) associated with upper or lower urinary tract symptoms.
Definitions of UTI by American Society of Transplantation:
Asymptomatic bacteriuria with no urinary or systemic symptoms of infection.
Acute simple cystitis with Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter.
Acute pyelonephritis/ complicated UTI with Fever, chills, malaise, hemodynamic instability, or leukocytosis; flank/allograft pain; or bacteremia with same organism as in urine.
Recurrent UTI if more than three UTIs in previous 12-month period.
Most renal transplant recipients the classical symptoms may not occur due to immunosuppressive therapy and kidney denervation, and UTI may present only with graft dysfunction, mild febrile illness or urosepsis.
The most common organisms found after transplantation are either gram negative (E coli, Klebsiella, and Pseudomonas aeruginosa) or gram positive (Enterococcus faecalis)
Gram negative pathogens are more common (E coli is the commonest organism isolated) than gram positive ones.
The incidence of isolation of multi-drug resistant bacteria (ESBL Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae) was more common in transplant recipients compared to general population.
Screening using simple urine culture is recommended in early transplant period.
Pre-operative risk factors for UTI post -transplant:
Female sex.
Diabetes mellitus.
Urological abnormalities.
Intraoperative risk factors:
Deceased donor.
Double J catheter.
Foley’s catheter for prolonged time.
Post-operative risk factors:
Excessive immunosuppression.
Acute allograft dysfunction
Allograft rejection.
Aim of the study:
Identify the prevalence and risk factors of UTIs post-transplant UTIs.
Assess the effect of UTIs on renal function and effect of UTIs on allograft function at 2 years post-transplant.
Identify and qualify the causative organisms, and antibiotics sensitivities.
Methods:
This was a retrospective observational study. It was conducted at a quaternary level hospital in Royal Brisbane and Women’s Hospital (RBWH), Australia.
Those patients with acute post-transplant follow-up were provided at RBWH from July 1st, 2011, to July 1st, 2016.
Inclusion criteria:
All patient >16 yrs. received their transplant at RBWH and being followed at the center for the last 2 years.
All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
Exclusion criteria:
Patients not completing their 2 years follow up at RBWH.
Patient received their transplant before or after the study time period.
UTI defined as a positive bacteriuria and received one or two courses of antibiotics, thus all the categories of UTI by the American Society of Transplantation Infectious Diseases Community of Practice were included.
The patients divided in two groups UTI and No UTI groups, UTI group sub-classified into cystitis or complicated UTI (systemic symptoms and a clinical profile mandating admission to hospital for parenteral antibiotic therapy).
72 patients include in this study had received their first renal transplant, 55 deceased donor, 7 living donor, and 10 with kidney-pancreas transplantation.
All base line characteristics were comparable among groups, including the immunosuppressive protocol, the indwelling catheter, and DJ stent times to remove them…etc.
Results:
20 patients experienced UTI during the study period (27.8% incidence).
8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
Among the UTI cohort group 77 events were reported:
The most common organisms are E. coli, klebsiella sp, pseudomonas.
55% (11/20) of the patients had at least one episode of complicated UTI/pyelonephritis, 45% (9/20) had at least one simple cystitis episode.
8% (6/77) of blood cultures obtained at time of a UTI episode were positive and identical to the urinary isolate.
The antibiotics used in treatment of UTI episode were penicillin and cephalosporin in 49% and 36%, respectively.
TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal in our cohort (66/71 = 93%)
Additional prophylactic antibiotics (6/7 with nitrofurantoin) were received by 35% of the UTI sub-group.
Discussion:
The incidence of UTIs in renal transplant patient was recorded at 27.8%. Similarities rates have been shown in other studies.
The risk factors identified in this study are like other studies.
They include the female gender and age. Surprisingly, pre-existing history of UTI and urogenital abnormality were not found to be risk factors. Low rates of E. coli bacteremia were noted, and no patients died because of UTI.
Trimethoprim usage for pneumocystis did not offer protection against UTI. In this study, UTIs affected the real function acutely during the episode. It did not impair renal function at two years post-transplant. The effectiveness of prophylactic antibiotics, impatient with frequent or recurrent UTIs was not clear.
It is difficult to generalize patients’ long-term allograft function using data two years post transplantation, but it may indicate the trend.
Risk factors and outcome results are:
On univariate analysis, risk factors for developing UTI are DM, old age and female sex, but type of transplant, HLA mismatch are not.
On adjusted analysis, female gender, and age) were statistically significant risk factors, all other variables were not statistically significant.
Despite acute kidney injury encountered with each UTI episode, no change in serum creatinine and GFR among all groups at 2 years.
Use of trimethoprim for Pneumocystis prevention did not provide protection.
Study limitations:
Retrospective nature, small sample size and relatively limited follow-up (only two years).
Study strength:
All forms of UTI including asymptomatic bacteriuria were treated, it identifies the risk factors that is consistent with previous studies.
Conclusion:
The study emphasizes the risk factors of UTI post-transplant, and the SMX-TMP is not protective of UTI.
In a retrospective research, antibiotics were not accurately defined.
The study highlights the concept of prophylactic antibiotics in conjunction with SMX-TMP.
Antibiotic prophylaxis for UTIs offers perspective on risk factor and treatment.
What is the level of evidence provided by this article?
A retrospective cohort study ,Level of evidence II .
Background
Urinary tract infections (UTI) are considered the commonest post renal transplant infections ranging between 10 and 98%. The cause of discrepancy is attributed mainly to the availability of the diagnostic tools and prophylactic measures. After long practice finally the last updates by the American Society of Transplantation Infectious Diseases Community of Practice 2019 guidelines managed to establish clear definitions for all UTI syndromes particularly: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), as well as recurrent UTI.
Unfortunately, the common ‘classical’ symptoms of UTI in the form of urinary frequency, dysuria, urgency or suprapubic pain, mostly don’t exist owing to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters. Thus the presentation may be vague as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine, highlighting the routine outpatient dipstick testing is mandatory in this critical population.
The most common organism encountered is Escherichia coli followed by other common enteric organisms as Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species. Risk factors may vary from preoperative considerations as female sex, diabetes mellitus and the presence of urological abnormalities. Could be also intraoperative due to the use of ureteric stents and prolonged indwelling bladder catheterisation. While postoperatively, the exposure to acute allograft dysfunction and rejection necessitating the excessive use of immunosuppression.
It is evident that the occurrence of UTIs in this population is hazardous as it poses the patients to the risk of increased morbidity, hospitalisation rates besides acute allograft dysfunction. The question then is does it affect long-term allograft function or reduce allograft or patient survival.
A huge study conducted by the United States Renal Data System registry for infections for more than 60,000 renal transplant recipients from 2000 to 2011 in the first year post renal transplantation concluded that 32% of patients had a UTI in the first year which was associated with a 41% increased relative risk of death.
Methods
This study is a retrospective observational one performed at the Royal Brisbane and Women’s Hospital (RBWH) for 2 years duration post renal transplantation.
The study population involved all adult renal transplant recipients (> 18 years old even simultaneous kidney-pancreas transplantation) as well as those having their post-acute transplant follow-up at RBWH from July 1st 2011 to July 1st 2016.
UTI is defined by the existence of bacteriuria proved by laboratory reports and receipt of one or more courses of antibiotics. Importantly, three consecutive sera creatinine were needed; ‘Pre-UTI’ was within 3 months before the episode, the ‘UTI episode’ within 2 weeks of recorded bacteriuria and ‘post UTI’ by 15 days to 3 months post UTI.
All UTI episodes were included from 1 month post renal transplantation up to 2 years. Severity was classified by the presence of simple cystitis or by complicated UTI/pyelonephritis requiring hospital admission for parenteral antibiotic therapy.
Statistical analysis were carried out using STATA version 15, Pearson’s Chisquared test and Fisher’s exact test. P-values less than 0.05 were significant.
Results
A total number of 72 patients (55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney pancreas transplants) were first renal transplant.
There was no association between the occurrence of UTI and induction therapy even those who received thymoglobulin induction which were only 3 patients (p = 0.20).
The mean age at transplantation was 45.5 years (median: 47, range: 17–71). All patients removed catheter 3–5 days post transplantation. Also, ureteric stents were removed 4–6 weeks post operatively.
In this study, 20 patients had at least one UTI over the study period with incidence rate for a UTI was 27.8%. The mean number of UTIs per person among all patients was 3.85. About 55% of the patients (11/20) in the UTI subgroup had at least one episode of complicated UTI/pyelonephritis. The other group 45% (9/20) had at least one simple UTI episode. Total of 33.8% of the UTI episodes were considered complicated UTI/pyelonephritis (26/77). It was found that only 8% (6/77) of blood cultures obtained at time of a UTI episode were positive.
ESBL-producing organism in 3.9% of urine cultures (3/77) was the most common. It had the feature of response to penicillin, gentamicin and carabepenem.
The study also confirmed that older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) are still considerable risk factors for developing UTI. In contrast, HLA mismatches and strong pre-existing history of UTIs were not found to be risk factors anymore.
Each UTI episode was associated with a mean increase in serum creatinine of 21 micromol/L (14.4%, SEM 5.20) and statistically significant (p = 0.027). While after resolution of the UTI, the estimated mean reduction was 16 micromol/L (9.1%, SEM 6.23) reduction in serum creatinine with statistical significance (p = 0.076).
Fortunately, there was no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between both groups with complicated UTI/pyelonephritis and simple UTI (p = 0.331) or even the rest of the whole cohort (p = 0.814).
Discussion
Similar to other studies, this work confirmed the high incidence of post renal transplant UTI about 27.8%. Concerning the known risk factors for developing a UTI as other studies only Female gender and age were the only significant risk factors while pre-existing history of UTI or urogenital abnormality are no more considered risk factors.
In 2016, a study elaborated that early removal of ureteric stents at 1 week was associated with a statistically significant lower rate of UTIs compared with routine stent removal at 4 weeks while our study found that they were not linked at all.
Our study fortunately proved low rates of ESBL-producing organisms UTI or bacteremia besides no deaths were encountered due to UTI. The use of trimethoprim for Pneumocystis prophylaxis was not associated with more protection against UTIs in our patients even when being used by 93% of patients at doses considered prophylactic for UTIs.
Among all groups, no significant difference in baseline serum creatinine levels was demonstrated.
Limitations were mainly being retrospective with small sample size and relatively limited follow up duration. In order to assess the patients’ long-term allograft function 2 year study duration is definitely not satisfactory.
Strengths were the wide application of the definition of UTI in all cases.
Conclusion
Other extensive studies are needed particularly to reevaluate the risk factor profile, treatment of UTIs and the doubtful benefit of antibiotic prophylaxis for UTIs.
Level of evidence is II.
Background:
UTI is the most common infection after renal transplantation, with an estimated 10-98% incidence. Updated 2019 guidelines unify definitions for asymptomatic, acute simple cystitis, acute pyelonephritis, complicated UTI, and recurrent UTI. Risk factors for post-transplant UTIs include pre-operative (host) factors, intra-operative factors and post-operative factors.
Methods:
This study included adult patients who received a renal transplant and had post-transplant care for 2 years, and defined UTI as the presence of bacteriuria on laboratory reports and receipt of antibiotics. Statistical analysis was performed using STATA version 15, with Pearson’s Chisquared test and Fisher’s exact test for non-correlated data.
Result :
72 patients were reviewed posttransplantation, with 95.7% receiving intravenous basiliximab or thymoglobulin and methylprednisolone, together with tacrolimus and mycophenolate.
Congenital/genetic and metabolic/vascular diseases were the most common causes of end-stage kidney disease leading to transplantation, with glomerulopathy also common. All patients had an indwelling catheter to measure urine output and a ureteric stent inserted.
The mean number of UTIs per person in the UTI sub-group was 3.85, and 55% of the patients had at least one episode of complicated UTI/pyelonephritis. TMP/SMX prophylaxis at a dose of 400/80 mg/day was almost universal, and additional prophylactic antibiotics were received by 35% of the sub-group as an adjunct. Older age, female gender, hyperglycaemia .
There was no significant difference in serum creatinine and estimated glomerular rate (eGFR) between those with and without a UTI, and no statistically significant difference between those with a complicated UTI/pyelonephritis and the rest of the cohort.
Discussion:
This study highlights the incidence of UTIs in a renal transplant population with 27.8% of patients experiencing a UTI. It identified risk factors for developing a UTI, such as female gender and age, and a pre-existing history of UTI or urogenital abnormality. Stent usage was associated with lower rates of UTI, and trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs. There was no significant difference in baseline serum creatinine levels between the two subgroups.
This study examined renal function at 2 years post-transplant for those experiencing a complicated UTI/pyelonephritis. The time-point of 2 years was chosen as a reference point due to the increased risk of UTIs in the initial 12 months and high levels of immunosuppression employed in this period.
Many of the reported risk factors for UTIs in this population cannot be mitigated, and vigilance and monitoring for hyperglycaemia is important for cardiovascular benefits. However, the effectiveness of prophylactic antibiotics is not clear.
Conclusion :
This study adds to the growing body of work around UTI management in the kidney transplant population, highlighting that UTIs are common and risk factors include female gender, older age and hyperglycaemia.
What is the level of evidence provided by this article?
level 2
Background
· Urinary tract infections (UTIs) are the most common infections after renal transplantation, with an estimated incidence of 10-98%. · The 2019 guidelines from the American Society of Transplantation Infectious Diseases Community of Practice have attempted to unify definitions for all UTI syndromes, including asymptomatic bacteriuria, acute simple cystitis, acute pyelonephritis, and recurrent UTI. · Risk factors for the development of a post-transplant UTI can be divided into pre-operative (host) factors, intraoperative factors, and postoperative factors. · Preoperative factors include female sex, diabetes mellitus, and the presence of urological abnormalities, intraoperative factors include kidney transplantation from a deceased donor, the use of ureteric stents, and prolonged indwelling bladder catheterization, and post-operative factors include acute allograft dysfunction and rejection. · The 2009 KDIGO guidelines recommend TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant.· Recent studies have shown a rising prevalence of resistant organisms in those with UTIs. · It is unclear if UTIs impair long-term allograft function or reduce allograft or patient survival. · This study aimed to identify the prevalence and risk factors for post-transplant UTIs and assess their effect on renal function during a UTI episode and if it resulted in declining allograft function at 2 years post-transplant.
Methods
· Retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women’s Hospital.
· Patient charts, pathology records, and dispensing histories were reviewed as part of this study and all UTIs from 2 years post-transplantation were captured.
Results
· Older age, female gender, hyperglycemia, and acute rejection episodes were risk factors for developing a UTI.
· Serum creatinine increased during a UTI episode and decreased after.
· Common organisms accounted for 82% of UTIs, with 70% requiring only a single course of antibiotic treatment.
· TMP/SMX prophylaxis did not influence the rate of UTI.
Discussion
· This study highlights the incidence of UTIs in a renal transplant population, with 27.8% experiencing a UTI.
· Risk factors for developing a UTI included female gender and age, early ureteric stent removal, low rates of UTI or bacteremia caused by ESBL-producing organisms, and trimethoprim usage for Pneumocystis prophylaxis.
· UTIs acutely affected renal function during an episode but did not impair overall renal function at 2 years post-transplant.
· Early detection and aggressive treatment of asymptomatic bacteriuria led to a milder profile of UTIs in our cohort, with only 8% of all UTI episodes having co-existing bacteremia and no statistically significant difference in renal function at 2 years post-transplant.
· Risk factors such as gender and age cannot be mitigated.
· Vigilance and monitoring for hyperglycemia are important for cardiovascular benefits.
· This study examined the effectiveness of trimethoprim prophylaxis and prophylactic antibiotics in reducing UTIs in the kidney transplant population.
· Risk factors were female gender, older age, and hyperglycemia.
· UTIs did not affect renal function at 2 years post-transplant, and ESBL organisms were relatively uncommon
· The evidence does not support treating asymptomatic bacteriuria in its own right, but clinicians would treat it if it is associated with an unexplained rise in serum creatinine.
· The study design was the retrospective, small sample size and limited follow-up, but the results were indicative of important trends.
Conclusion,
· There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those with and without a UTI.
===========================================
Level of Evidence II
I like your well-structured detailed summary, level of evidence, limitations and strengths based on analysis and take home messages.
1.Please summarise this article.
Introduction
Aims of the study
Methods:
Results
Discussion
Conclusion
=======================
2.What is the level of evidence provided by this article?
I like your well-structured detailed summary, level of evidence, limitations and strengths based on analysis and take home messages.
Please summarise this article
Introduction:
UTI is the most common infections post-transplant with variable incidence range 10-98%, this discrepancy due to different UTI definitions, and diagnostic protocols, and antibiotic prophylaxis used among studies.
Definitions of UTI by American Society of Transplantation:
Pre-operative risk factors for UTI post transplant:
Female sex.
Diabetes mellitus.
Urological abnormalities.
Intraoperative risk factors:
Deceased donor.
Double J catheter.
And Foley’s catheter for prolonged time.
Post-operative risk factors:
Excessive immunosuppression.
Acute allograft dysfunction
Allograft rejection.
Aim of the study:
To identify the prevalence of post transplant UTIs.
To identify the risk factors for post-transplant UTIs.
To assess effect of UTIs on renal function.
To assess effect of UTIs on allograft function at 2 years post transplant.
To identify and qualify the causative organisms, and antibiotics sensitivities.
Methods:
Inclusion criteria:
All patient >16 yrs received their transplant at RBWH and being followed at the center for the last 2 years.
All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant.
Exclusion criteria:
Patients not completing their 2 years follow up at RBWH.
Patient received their transplant before or after the study time period.
Results:
= On univariate analysis; risk factors for developing UTI are: DM, old age and female sex, but type of transplant, HLA mismatch are not.
= On adjusted analysis, female gender and age) were statistically significant risk factors, all other variables were not statistically significant.
= In spite of acute kidney injury encountered with each UTI episode, no change in serum creatinine and GFR among all groups at 2 years.
= Use of trimethoprim for Pneumocystis prevention did not provide protection.
Study limitations: Retrospective nature, small sample size and relatively limited follow-up (only two years).
Study strength: all forms of UTI including asymptomatic bacteriuria were treated, it identifies the risk factors that is consistent with previous studies.
Conclusion:
The study emphasizes the risk factors of UTI post-transplant, and the SMX-TMP is not protective of UTI.
The study highlights the concept of prophylactic antibiotics in conjunction with SMX-TMP.
What is the level of evidence provided by this article?
Level of evidence II C – outcome retrospective cohort study.
I like your well-structured detailed summary, level of evidence, limitations and strengths based on analysis and take home messages.
Summary.
Background
UTI are most common infections in post-transplant period with incidence rates ranging between 10-98%.
Classical UTI symptoms of frequency, dysuria and suprapubic pain are usually absent in kidney recipient due to innervation of the kidney and ureters.
Thus in kidney recipients UTI may present as new febrile illness, asymptomatic rise of serum creatinine and urosepsis.
GN rods are the most common causative pathogens with common organisms being E.coli, klebsiella, pseudomonas aeroigenosa and enterococcus species.
Risk factors for developing UTI can be grouped into:
KDIGO 2009 guidelines recommends PCP prophylaxis with TMP/SMX for at least 6 months.
There has been a rise of resistant UTI organisms whilst still on prophylaxis.
UTI’s are associated with increased mortality, morbidity and allograft dysfunction.
Aim of the study
To identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode.
To assess if UTI resulted in declining allograft function at 2years post-transplant.
To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode. Utilisation rates of TMP/SMX prophylaxis were also investigated
Methodology
Retrospective observational study.
Inclusion criteria
All adult patients returning to our centre who had their post-transplant care with us for 2 years from their renal transplant date and within the specified time frame of 1st July 2011 to 1st July 2016.
Exclusion criteria
Those patients returning to our centre within the above timeframe but not completing their 2 years of post-transplant care with us, as well as those who received their transplant outside the specified time frame.
Definition of terms
UTI was defined as the presence of bacteriuria on laboratory reports and receipt of one or more courses of antibiotics.
This thus included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics.
Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine and deemed clinically necessary.
Results
72 patients were recruited- 55DCD, 7 LKD and 10 simultaneous kidney-pancreas transplant.
All received induction therapy with either basiliximab or ATG with methylprednisolone.
Maintenance therapy was triple therapy.
All patients had an indwelling catheter that was removed 3-5 days after transplant.
All patients had a ureteric stent that was removed 4-6 weeks after transplant.
20/72 had a UTI with incidence rate of 27.8%.
11/20 (58%) had a complicated UTI.
ESBL producing organism was isolated in 3.9%.
66/71 were on TMP/SMX prophylaxis.
Risk factors associated were female gender, hyperglycaemia and acute rejection episodes.
With each UTI episode there was a mean increase in Scr that decline after the episode.
There was no statistical difference in eGFR between those with UTI and those without from baseline to 2 years post-transplant.
Discussion
This study identified risk factors for developing UTI similar to other studies.
TMP/SMX use didn’t confer protection for UTI in this study.
In this study UTI acutely affected renal function with resolution to baseline 2 weeks post-UTI.
UTI didn’t impair renal function at 2 years post-transplant.
Limitations
The study design this was a retrospective observational study.
The sample size was small.
There was limited followup of the patients.
Strengths.
They utilised an all encompassing UTI definition.
Level of evidence:2
I like your well-structured detailed summary, level of evidence, limitations and strengths based on analysis and take home messages.
Background
Urinary tract infections (UTI) are common infections in renal transplant recipients. The “classical” symptoms of UTI are usually absent in renal transplant recipients due to immune suppression and surgical denervation of the transplanted kidney and ureters. Therefore, UTI, in a renal transplant recipient may present as a new febrile illness, urosepsis, or an asymptomatic rise in serum creatinine. There are a wide variation of UTI syndromes, which include asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI) and recurrent UTI.
The main pathogens causing UTIs in both non-transplant and transplant patients are gram-negative rods, including E. coli, K. pneumoniae, P. aeruginosa and Enterococci species. Unfortunately there is an increasing incidence and prevalence of MDR pathogens globally. Despite the use of TMP/SMX universally for the first six months post-transplant, there is an increasing incidence of UTIs, portraying the increasing resistance of these organisms to TMP/SMX.
Risk factors for developing UTI after transplantation include:
For kidney transplant recipients UTIs are associated with increased morbidity and hospitalization.
The aim of this study was to identify the prevalence and risk factors for post-transplant UTIs and assess the UTIs effect on renal function during a UTI episode. It also aimed to assess if the UTI resulted in declining allograft function at two years post-transplant.
Methods
This was a retrospective observational study. It was conducted at a quaternary level hospital in Brisbane, Australia. All adult patients who were followed up at the hospital for two years after the renal transplant were included. The patients excluded were patients who had not completed two years post-transplant care with the hospital, and those who received the transplant outside the specified timeframe.
UTI was defined as the presence of bacteriuria on lab reports and receipt of one or more courses of antibiotics. This definition included all cases of acute simple cystitis, transplant pyelonephritis and asymptomatic bacteriuria if treated with antibiotics. Asymptomatic bacteriuria was only treated if there was an unexplained rise in serum creatinine, and was clinically necessary to treat.
Results
72 patients were reviewed after transplantation over a five-year duration. There were 55 deseased donor transplants, 7 living related kidney transplants and 10 simultaneous kidney and pancreas transplants. Induction therapy included either IV basiliximab or thymoglobulin and methylprednisolone together with tacrolimus and mycophenolate. The mean age of transplantation was 45.5 years. All patients had an indwelling catheter to measure urine output, and this was routinely removed 3 to 5 days after transplantation. All patients had a ureteric stent inserted and it was routinely removed 4-6 weeks after the procedure, unless the patient developed an early UTI, in which case it was removed earlier.
20 patients experienced at least one UTI over the study duration. 55% of the patients in the UTI sub group had at least one episode of complicated UTI. The remaining 45% in the sub group had at least one simple UTI episode. E. coli was detected in 3.9% of urine cultures and all the isolates were sensitive to penicillin, gentamicin and carbapenem. TMP/SMX treatment was universal, unless the patient had side effects or an allergy. With each UTI, episode the serum creatinine increased by 21 µmol/l.
Discussion
The incidence of UTIs in renal transplant patient was recorded at 27.8%. Similarities rates have been shown in other studies. The risk factors identified in this study are similar to other studies. They include the female gender and age. Surprisingly, pre-existing history of UTI and urogenital abnormality were not found to be risk factors. Low rates of E. coli bacteremia was noted and no patients died as a result of UTI. Trimethoprim usage for pneumocystis did not offer protection against UTI. In this study, UTIs affected the real function acutely during the episode. It did not impair renal function at two years post-transplant. The effectiveness of prophylactic antibiotics, impatient with frequent or recurrent UTIs was not clear. It is difficult to generalize patients’ long-term allograft function using data two years post transplantation but it may indicate the trend.
Study Limitations
Level of Evidence
This is a retrospective study. LOE II
I like your well-structured detailed summary, level of evidence, limitations and strengths based on analysis and take home messages.
Introduction
The current study is a retrospective study (level of evidence III) evaluating 72 renal transplant recipients treated in the Royal Brisbane and Women’s Hospital and follow them over a 2 years period after transplantation, regarding the incidence and risk factors for UTI, graft function during, after a UTI episode and 2 years after transplantation and the antibiotic susceptibility of the organisms isolated, and whether the incidence of UTI changed by the use of SMX-TMP prophylaxis or not.
Results
Conclusion
I like your well-structured detailed summary, analysis and take home messages.
Why level 3 evidence for this article?
Do you mean prophylactic rotating antibiotics once a day to be changed every month and then repeating the cycle after 3 months and so on?
Background:
After kidney transplantation, urinary tract infections (UTI) account for 10–98% of infections. Variations in study definitions, diagnostic criteria, and prophylactic antibiotic use explain the large range. Hence, UTI diagnosis in renal transplant patients has been inconsistent till recently. The 2019 American Society of Transplantation Infectious Diseases Community of Practice recommendations strive to standardize terminology for all UTI symptoms, including asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurring UTI.
Methods:
RBWH, a quaternary hospital in Brisbane, Australia, undertook retrospective observational research. Early postoperative transplant patients are treated here. All adult patients (18+) who got a renal transplant (including simultaneous kidney-pancreas transplantation) and received post-acute transplant follow-up at RBWH from July 1, 2011 to July 1, 2016, had their baseline demographics gathered.
Results:
20 (27.8%) of these individuals developed UTIs. In unadjusted analysis, UTI risk variables were older age, female gender, hyperglycemia, and acute rejection episodes. In adjusted analyses, female gender (OR 4.93) and age (OR 1.03) were significant UTI risk variables. During a UTI episode, serum creatinine increased by 14.4% (SEM 5.20), which was statistically significant (p = 0.027), and it decreased by 9.1% (SEM 6.23) thereafter, heading toward significance.
(p = 0.076). 82% of UTIs were caused by Escherichia coli and Klebsiella pneumonia, and 70% required just one antibiotic course. Most UTIs utilized penicillin (49%) or cephalosporin (36%). TMP/SMX prophylaxis for Pneumocystis carinii pneumonia did not affect UTI rates in > 90% of the group.
Discussion:
The research found UTI risk variables that have been shown in prior studies.
Female gender and age were the only risk variables that achieved statistical significance in the adjusted analysis. Surprisingly, a pre-existing UTI or urogenital abnormalities was not a risk factor in the unadjusted analysis.
In this trial, UTIs rapidly impaired renal function, but renal function returned to baseline after 2 weeks. UTIs did not affect renal function two years post-transplant.
A wide definition of UTI included people who were clinically regarded to need treatment, not simply symptomatic patients.
Due to early detection and aggressive treatment of clinically significant asymptomatic bacteriuria, our cohort had a milder profile of UTIs, with only 8% of UTI episodes having co-existing bacteremia and no statistically significant difference in renal function at 2 years post-transplant for those with complicated UTIs.
Level of evidence: II
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions.
Summary of the Article
Background
a) Inconsistent definitions and diagnostic criteria.
b) A variable utilization rate of antibiotics.
a) Asymptomatic bacteriuria.
b) Acute simple cystitis (lower UTI).
c) Acute pyelonephritis (complicated UTI) plus fever and chills.
d) Recurrent UTI.
a) Urinary frequency.
b) Dysuria.
c) Urgency or suprapubic pain.
d) In immunocompromised patients may present as a new febrile illness, urosepsis, and or asymptomatic rise in S.Cr.
a) E.coli.
b) Klebsiella pneumonae.
c) Pseudomonas aeroginosa.
d) Enterococcus spp.
e) MDR G-ve.
a) Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae.
b) Carbapenem-resistant Enterbacteriaceae.
Risk factors of UTI in KTR;
a) female sex.
b) DM.
c) Urological abnormality.
a) Deceased donation.
b) ureteric stents.
c) Prolonged indwelling catheterization.
a) Acute allograft dysfunction.
b) Rejection.
c) Extensive immunosuppressants.
KDIGO 2009 guidelines recommend TMP-SMX for prophylaxis against pneumocystis carinii for at least 6 months post-KT, (although proved by a recent study of the developing resistance whilst on prophylaxis).
Discussion
a) Female gender.
b) Age.
c) Stent usage (early removal of the stent is vital for reducing the rate of UTI).
a) There is a well-documented increased risk of UTIs in the initial 12 months post-KT, (due to surgical procedures in early Tx, and massive immunosuppressants).
b) 2 years represents a reliable and accessible dataset in terms of dispensing and medical record accuracy.
what is unclear in this study
Limitations
Strengths
Level of evidence
Level ((II))
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions.
Summary of the article
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
This is a retrospective observational study of 72 renal transplant patients over a 5-year period who were managed in Australia at the Royal Brisbane and Women’s Hospital. The study aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant.
1. The estimated incidence of UTI in post-transplant period ranges between 10 and 98%.
2. Classification of asymptomatic bacteriuria and UTI in renal transplant recipients according to American Society of Transplantation Infectious Diseases Community of Practice:
· Asymptomatic bacteriuria: No urinary or systemic symptoms of infection.
· Acute simple cystitis: Dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter.
· Acute pyelonephritis/ complicated UTI: Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain; or bacteremia with same organism as in urine. Dysuria, urgency, frequency, suprapubic pain may or may not be present.
· Recurrent UTI: ≥3 UTIs in prior 12 month period.
3. Gram-negative rods are the main pathogens causing UTIs in both the non-transplant and transplant populations. Escherichia coli is the most common uropathogen and other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species.
4. Risk factors for post-transplant UTI:
a) pre-operative (host) factors: female sex, diabetes mellitus and the presence of urological abnormalities.
b) intra-operative factors: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterization.
c) post-operative factors: acute allograft dysfunction and rejection as well as excessive immunosuppression as a result of rejection episodes.
UTI episodes in the study group(77 patients)
a) Most common organisms:
· E.coli; 41 (53%)
· Klebsiella species; 22 (29%)
· Pseudomonas aeruginosa; 4 (5%)
· Enterococcus faecalis; 3 (4%)
· ESCAPPM organisms; 3 (4%)
· Culture negative; 2 (3%)
· Other; 2 (3%)
b) Number of antibiotics received per episode:
· One; 54 (70%)
· Two; 18 (23%)
· Three; 5 (6%)
c) Class of antibiotics used:
· Penicillins; 38 (49%)
· Cephalosporins; 27 (36%)
· Fluoroquinolones; 12 (16%)
· Carbapenems; 3 (4%)
· Other; 14 (18%)
Study’s Result and Discussion
1. With each UTI episode, there was a mean increase in serum creatinine of 21 micromol/L.
2. Female gender and age were the only risk factors for UTI.
3. Trimethoprim usage for Pneumocystis prophylaxis did not confer protection against UTIs in the study’s group.
4. UTIs acutely affected renal function dur- ing an episode, with renal function approaching baseline from 2 weeks post UTI.
5. UTIs did not im- pair overall renal function at 2 years post-transplant.
Study’s Limitations
· Retrospective nature.
· Small sample size.
· Limited follow- up.
The level of evidence provided by this article:
This is a retrospective study with level of evidence grade 3.
I like your well-structured detailed summary, limitations and strengths based on analysis and take home messages.
Why level 3 evidence for this article?
Introduction:
– UTI is the most common infection after renal transplantation.
– It has significant consequences of UTIs with increase morbidity and hospitalization rates, acute allograft dysfunction. It may reduce graft and patient survival.
– Updated 2019 guidelines AST/IDCP have attempted to unify definitions for all UTI syndromes.
– E. coli is the most common uropathogen and MDR gram negative bacteria are increasing in number.
– Multiple risk factors contribute to increase the risk.
Study Aim:
– Identify the prevalence and risk factors for post-transplant UTIs
– Assess UTIs’ effect on renal function during a the episode and 2-years post-Tx.
– Identify the causative organism, the class of antibacterial used.
– Investigate the utilization rates of TMP/SMX prophylaxis.
Methods:
– Retrospective study over 5-year period (2011- 2016).
– Included all adult patients (> 18 years old) who received a KT (including Simultaneous kidney- pancreas) whose post-acute transplant follow-up was provided at RBWH.
– All-encompassing definition of UTI included.
– To estimate renal function: 3 consecutive sera creatinine were reviewed. ‘Pre-UTI’; within 3 months prior to an episode, ‘UTI episode’ was within 2 weeks of a recorded bacteriuria and ‘post UTI’ was 15 days to 3 months post
a UTI episode.
– All UTIs from 2 years post transplantation were captured.
– Patients classified according to the presence or absence of at least one UTI episode, and further classified according to UTI severity.
– Patient charts, pathology records and dispensing histories were reviewed
– All patients had an indwelling catheter removed at POD 3–5 days and ureteric stent removed at 4-6 weeks.
Results:
– Study included 72 patients, 52 (no UTI ), 20 (had UTI)
– The incidence rate for a UTI was 27.8%.
– E. coli and Klebsiella accounted for 82% of UTI episodes.
– 33.8% of the UTI episodes were classified as a complicated UTI/ pyelonephritis
– ESBL-E.coli isolated in very low rate.
– On unadjusted analysis; older age, female gender, hyperglycaemia and acute rejection episodes were risk factors for developing a UTI.
– Adjusted analysis showed female gender and age were statistically significant risk factors for a UTI.
– Serum creatinine increased by 14.4 % during UTI episode and decline by 9.1% after treatment.
– No significant change in serum creatinine and eGFR from baseline out to 2 years post-transplant
between those with and without a UTI complicated or simple.
– TMP/SMX prophylaxis for PCP did not provide protection against UTIs, despite 93% of patients on this treatment.
-70% of UTI cases requiring only a single course of antibiotic treatment.
-The antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
Conclusions:
-There was no significant change in serum creatinine and eGFR from baseline to 2 years post-transplant between those with and without a UTI.
-Prophylactic TMP did not confer protection against UTI.
Limitations: retrospective nature, small sample size and relatively limited follow up
Level of evidence: retrospective observational study level 2
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions. I wish you could have highlighted that, “in this retrospective research, antibiotics were not accurately defined.”
Please summarise this article.
Introduction
o UTIs are the most common of infections after renal transplantation with an estimated (incidence is 10-98%)
o The classical symptoms of UTI (urinary frequency, dysuria, urgency or suprapubic pain) are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters
o UTI in a renal transplant recipient may present as a new febrile illness, urosepsis or an asymptomatic rise in serum creatinine
o The main pathogens causing UTIs are gram-negative rods (in both the non-transplant and transplant populations)
o Escherichia coli is the most common organism and (other common enteric organisms include Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococci species)
o UTIs increase morbidity and hospitalisation rates as well as acute allograft dysfunction
Risk factors for the development of a post-transplant UTI:
1. pre-operative (host) factors: female sex, DM, and the presence of urological abnormalities
2. intra-operative factors: kidney transplantation from a deceased donor, the use of ureteric stents and prolonged indwelling bladder catheterisation
3. post-operative factors: acute allograft dysfunction and rejection and excessive immunosuppression (as a result of rejection episodes)
Definitions for UTI syndromes (American Society of Transplantation Infectious Diseases Community of Practice guidelines 2019):
1. Asymptomatic bacteriuria: no urinary or systemic symptoms of infection
2. Acute simple cystitis: dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent/ nephrostomy tube/chronic urinary catheter
3. Acute pyelonephritis/ complicated UTI: Fever, chills, malaise, haemodynamic instability, or leukocytosis (without other apparent etiology); flank/allograft pain; or bacteremia with same organism as in urine. Dysuria, urgency, frequency, suprapubic pain may or may not be present
4. Recurrent UTI: ≥3 UTIs in prior 12month period
Aim of the study: identify the prevalence and risk factors for post-transplant UTIs and assess UTIs’ effect on renal function during a UTI episode and if they result in declining allograft function at 2years post-transplant
Methods
o This retrospective observational study was conducted at a quaternary hospital in Australia (the Royal Brisbane and Women’s Hospital) from July 1st 2011 to July 1st 2016
o 72 patients were reviewed post transplant over a 5-year period
o All UTI episodes were included from 1 month after renal transplantation up to 2 years post-transplant
o They included all adult patients returning to theirr centre who had their post-transplant care with them for 2 years from their renal transplant date
Results
o 72 patients were followed post transplant over a 5-year period (all had received their first renal transplant; 55 deceased donor transplants, 7 living related kidney transplants and 10 simultaneous kidneypancreas transplants
o 20 patients (27.8%) had at least one UTI
o Risk factors for developing a UTI on unadjusted analysis were Older age, female gender, hyperglycaemia and acute rejection episodes
o Female gender and age were statistically significant risk factors for a UTI on adjusted analysis
o There was a 14.4% increase in serum creatinine during a UTI episode, which was statistically significant
o Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment
o The antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs
o The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with >90% of the cohort using this treatment
Discussion
In this study, UTIs acutely affected renal function during an episode, with renal function approaching baseline from 2 weeks post UTI
UTIs did not impair overall renal function at 2 years post-transplant
The time-point of 2 years post-transplant was chosen as a reference point for a number of reasons:
1. There is a well documented increased risk of UTIs in the initial 12 months post-transplant, more specifically, in the initial 3-6 months, due to the surgical procedure itself and high levels of immunosuppression employed in this period
2. From a pragmatic perspective, 2 years represented a reliable and accessible dataset in terms of dispensing and medical record accuracy
Limitations of the study:
1. Retrospective study
2. small sample size
3. relatively limited follow-up
Conclusionso No significant change in serum creatinine and eGFT from baseline to 2 years post-transplant between those with and without a UTI
What is the level of evidence provided by this article?II (retrospective observational study)
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions. I wish you could have highlighted that, “in this retrospective research, antibiotics were not accurately defined.”
-Summary
Introduction
UTI represent the most common infection post renal transplant.
Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases
Community of Practice unified the definitions of the following
Asymptomatic bacteriuria has no urinary or systemic symptoms of infection
Acute simple cystitis presenting by dysuria, urinary urgency/frequency, or suprapubic pain; but no systemic symptoms and no ureteral stent,nephrostomy tube,chronic urinary catheter
Acute pyelonephritis (complicated UTI) presents with fever, chills, malaise, haemodynamic instability, or leukocytosis ; flank/allograft pain;or bacteremia with same organism as in urine with or without dysuria, urgency, frequency, suprapubic pain
Recurrent UTI ≥3 UTIs in the last 12 month .
Classic manifestations of dysuria and suprapubic pain may be absent in transplated population due to the denervation of the renal graft and immunosuppressives intake .
Therefore in renal transplant recipients UTI can manifest by fever , urosepsis ,increased creat level ,thereby routine urine dipstick testing is crucial.
Gram negative organisms as Ecoli ,Klebseilla pneumoniae, Pseudomonus and Enterococci are the common pathogens to cause UTI in transplanted and non transplanted patients.
Multidrug resistance bacterial strains as extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae and carbapenem -resistant Enterobacteriaceae are emerging .
Risk factors :
-preoperative : female gender , diabetes mellitus and urological abnormalities.
-intraoperative: using a renal graft from a deceased donor, ureteric stents and prolonged indwelling bladder catheterisation
-postoperative: acute allograft dysfunction , rejection and excessive immunosuppression
2009 KDIGO guidelines recommends TMP/SMX for Pneumocystis carinii prophylaxis for at least 6
months after-transplant which lead to arising of resistant stains.
The sequelae of UTI in this group of patients is hazardous it can lead to increased morbidity and allograft dysfunction
Aim of the study is to detect the prevalence and risk factors for post-transplant UTIs and evaluate it’s impact on renal function during a UTI episode and if it can decrease allograft function at 2 years post-transplant.
Methods
This is a retrospective study on 72 renal transplant recipients within 5-year period treated at
the Royal Brisbane and Women’s Hospital. Patient data including the charts, pathology records and histories were revised and all UTI cases 2 years after transplantation were included.
Results
Of these patients, 20 had at least one UTI. Risk factors for UTI were old age , female gender ,hyperglycaemia and acute rejection episodes. There was a 14.4% statistical significant increase in serum creatinine during a UTI episode and a 9.1% nearly statisticaly significant decrease in serum creatinine after the UTI episode.
Common organisms (Escherichia coli and Klebsiella pneumoniae) representing 82% of UTI episodes with 70% of UTI cases requiring one course of antibiotic treatment. Antibiotics used were penicillin (49%) or cephalosporin (36%) . TMP/SMX used for Pneumocystis carinii pneumonia prophylaxis did not affect UTI rate as > 90% of the cohort used it .
Discussion
This study confirmed that UTI is the most common infection after renal transplantation.
Regarding the risk factors it revealed that female gender and age were the only risk factors with statistical significance and a pre-existing history of UTI or urogenital abnormality were not found to be a risk factors.
One study demonstrated that early ureteric stent removal at 1 week was associated
with lower rate of UTIs compared to conventional removal at 4 weeks.
ESBL rate was low in the current study.
Trimethoprim use for Pneumocystis prophylaxis did not show to be protective against UTIs in
the included patients.
This study noticed that UTIs acutely affects renal function during an episode, with renal function nearly reaching baseline 2 weeks post UTI, meanwhile UTIs did not affect overall renal function at 2 years post transplant.
This could be explained by the broad UTI definition and the early detection and proper treatment of early ASB leading to milder forms of UTI .
Other studies showed that severe UTIs and urosepsis exert a negative impact on long-term renal function.
2 years period time point was chosen due to high UTI risk in the first year post transplant and in the first 6 months post transplant due to surgical procedures and extensive immunosuppression also due to more medical records accuracy for evaluation.
It is not known the efficient monitoring and surveillance of UTIs that need to be done in the view of relative ineffectiveness of trimethoprim in decreasing UTI and the non-significant difference in renal function at 2 years post-transplant between the simple UTI and complicated cases.
The efficiency of prophylactic antibiotics in patients with frequent or recurrent UTIs is unknown
Limitations are being retrospective including small, sample size and short follow up period .
Strength including all UTI definition involving all cases of clinically significant asymptomatic bacteriuria, cystitis and transplant pyelonephritis; that is representative of current treatment strategies for transplant recipients.
Conclusions
Serum creatinine and e GFR did not vary significantly from
baseline to 2 years post-transplant between those with and without a UTI.
Results provided by this study are suitable for low immunosuppressed transplanted cases .
Also acknowledged risk factors, treatment of UTIs and the antibiotic prophylaxis for UTI were well addressed
-level of evidence is II as a retrospective observational study
I like your well-structured detailed summary, classification of the level of evidence, analysis and conclusions.
Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia
Please summarise this article.
Background
Classification of asymptomatic bacteriuria and UTI in renal transplant recipients
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Methods
====================================================================
Results
====================================================================
Discussion
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Conclusion
Antibiotic prophylaxis for UTIs offers perspective on risk factor and treatment.
In a retrospective research, antibiotics were not accurately defined.
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What is the level of evidence provided by this article?
The level of evidence is 2
=================================================================
I like your well-structured detailed summary, level of evidence, analysis and conclusions. I understand why you have written, “in a retrospective research, antibiotics were not accurately defined.”
Typing whole sentence in bold amounts to shouting.
Many thanks Prof.Sharma
UTI in KTR at a quaternary care center in Australia
⭐⭐⭐⭐Summary:
· UTI is the commonest infection after KT, it is still debatable that its induced acute allograft dysfunction may have poor consequences on both graft and patient outcome.
· The current study concluded that:
o Although UTI can cause acute graft dysfunction, the creatinine normalized mostly within 2 weeks of UTI and the long term GFR was not affected at 2 years of follow up.
o Most common isolated organism were Escherichia coli and Klebsiella pneumonia( 82% of UTI episodes). Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs.
o Use of prophylactic SMX-TMP did not decrease incidence of UTI. However, it still recommended since KDIGO 2009 recommendation.
o MDR bacteria as extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae are already present in Australia and often require the deployment of much older antibiotics, some of which are nephrotoxic, this may be related to immigration and fusion of plasmids from different starins.
· Updated 2019 guidelines from the American Society of Transplantation Infectious Diseases Community of Practice have attempted to unify definitions for all UTI syndromes including: asymptomatic bacteriuria, acute simple cystitis (lower UTI), acute pyelonephritis (complicated UTI), and recurrent UT.
· Pain and dysuria are often absent in the KTR due to the combination of immunosuppression medications and surgical denervation of the transplanted kidney and ureters. So UTI can be presented by fever, sepsis and rising creatinine (acute graft dysfunction).
· TMP can cause reversible increase in serum creatinine by inhibiting the tubular secretion of creatinine.
· Risk factors for UTI: female gender, DM and presence of pre-existing urological abnormalities and recurrent UTI episodes, deceased donor, prolonged use of ureteric stents and indwelling bladder catheter, excess immunosuppression as frequent episodes of acute allograft dysfunction and use of ATG and MMF.
⭐⭐Level of evidence: retrospective observational study (level 2)
Points of weakness: being retrospective (no accurate definitions as any case treated with antibiotics whether acute simple cystitis, transplant pyelonephritis or asymptomatic bacteriuria was included).
I like your well-structured detailed summary, level of evidence, analysis and conclusions.
Urinary tract infections in renal transplant recipients at a quaternary care center in Australia.
Background.
UTI post kidney transplant is considered the most common infection in this group due to immunosuppreive state, multiple -comorbidities, use of ureteric stents, prolonged indwelling bladder catheterization and urinary tract procedure, the usual symptoms of UTI, which includes urinary frequency, dysuria, urgency or suprapubic pain, are often absent in the renal transplant population due to the combination of immunosuppression and surgical denervation of the transplanted kidney and ureters, Escherichia coli is the most common uropathogen.
Using of TMP/SMX for prophylaxis against Pneumocystis carinii for at least 6 months post-transplant, lead to rising prevalence of resistant organisms in those with UTIs whilst on prophylaxis, we should bear in mind that UTIs in this population are serious with increased morbidity and hospitalization rates, as well as acute allograft dysfunction but still unclear if UTIs impair long-term allograft function or reduce allograft
or patient survival.
Aim of the work:
1-To identify the prevalence and risk factors for post-transplant UTIs, it is effect on renal function during a UTI episode. And if UTI resulted in declining allograft function at 2 years post-transplant.
2-To quantify which organisms were causative of UTI and collected data on classes of antibiotic employed, as well as number of different antibiotics employed per episode.
3-And utilization rates of TMP/SMX prophylaxis were also investigated.
Methods.
A retrospective study of 72 renal transplant patients over a 5-year period who were managed at
the Royal Brisbane and Women’s Hospital. Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were included .
Results:
1-There was no association with UTI for those that received thymoglobulin induction.
2-The incidence rate for a UTI was 27.8% across the whole cohort.
3-ESBL-producing organism is isolated in 3.9% of urine cultures.
4-Female gender (, hyperglycemia and acute rejection episodes were all risk factors for developing UTI.
5-There was no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI.
6-There was also no statistically significant difference in change in serum creatinine from baseline out to 2 years post-transplant between those with a complicated UTI/pyelonephritis versus those with a simple UTI.
7-No effect from using TMP/SMX prophylaxis for Pneumocystis carinii pneumonia, which did not influence the rate of UTI, with > 90% of the cohort using this treatment.
Conclusion:
UTI is the most common infection post KTX but with treatment of UTI, there is no significant change in serum creatinine and estimated glomerular rate (eGFR) from baseline out to 2 years post-transplant between those with and without a UTI, and no impact from using TMP/SMX prophylaxis on the incidence of UTI.
Level of evidence is 3 (a retrospective study).
What is your reason for allocating level 3 to this report? I like your summary and analysis. I appreciate that you have written strengths and limitations.
Introduction:
Aim of the study:
Methods:
Result & discussion:
Limitations of the study:
Level of evidence is 3 (retrospective study).
Hi Dr Ban,
What is your reason for allocating level 3 to this report? I like your summary and analysis.
I appreciate that you have written strengths and limitations.
Article -5
Q1.
Introduction
· Urinary tract infections (UTI) are the most prevalent infections following kidney transplantation (KT)
· Incidence is in the range of 10 to 98% probably due to lack of standardized definition
· Routine urine dipstick in transplant outpatients contributed to early diagnosis of asymptomatic bacteriuria
· The common organisms are gram negative rods such as E. coli. Other organisms include K.pneumonia, P.aeruginosa and Enterococci species.
· The number of multi-drug resistant gram negative are also increasing worldwide
· UTI may be associated with increased morbidity and risk of allograft dysfunction
· The objective of this study was to look at the prevalence, risk factors, impact of the allograft function at 2 years, the type of the organism, antibiotic treatment, and the protective effect of trimethoprim/sulfamethoxazole (TMP/SMX)
· UTI was defined as bacteriuria and exposure to one or more antibiotics course
Methodology
· Retrospective analysis carried out at the Royal Brisbane & Women Hospital (RBWH)
· From July 2011 to July 2016
· They included 72 kidney transplant recipients
· The medical records of the patients were reviewed in details including treatment history and any episode of UTI 2 years after transplantation
· Patients were divided into two groups based on the presence or absence of UTI
· Those whose required hospital admission because of UTI were categorized as complicated UTI or pyelonephritis
Results
· Around 20 patients suffered from at least one attack of UTI
· Risk factors for UTI after adjusted statistics were female gender and age
· There was 14% elevation in serum creatinine following an episode of UTI and 9% decreased in creatinine after treatment of UTI
· Up to 82% of UTIs were caused by E. Coli and Klebsiella pneumoniae
· Two-third of the UTI responded well to a single dose antimicrobial therapy
· The order of the antibiotics used for treatment of UTIs was penicillin in 49% of cases followed by cephalosporin in 36% of cases
· The use of TMP/SMX did not protect against development of UTI
Limitations
· Retrospective
· Small sample size
· Limited follow up period
Strength
· They included all spectrum of UTI across renal transplantation
Conclusion
· Female gender, age were the most important risk factors for UTI and E. Coli was the most common organism. All patients with or without history of UTI had normal allograft function at two years
Q.2
· Retrospect, observational study level 3
Hi Dr Ben,
What is your reason for allocating level 3 to this report? I like your summary and analysis.
I appreciate that you have written strengths and limitations.
Thnxs prof, this was retrospective cohort, level II
SUMMARY
Introduction
Following successful kidney transplantation, one of the most feared infections is urinary tract infection as it can be accompanied by a prolonged hospital stay and sometimes allograft rejection or impaired recipient survival if severe. UTI in kidney transplantation has a wide incidence rate of 10%-98% partly due to various definitions used for the infection.
Definition of UTI according to the 2019 American Society of Transplantation Infectious Disease Community of Practise
The most commonly implicated organism both in kidney transplant and non-kidney transplant patients is E.coli, while others are Klebsiella pneumonia, Pseudomonas aeruginous, and enterococci species. Of note is the increasing global rate of multidrug resistance against many of the available antibiotics
Risk factors for the development of UTI
a) Preoperative factor: female sex, DM, urological abnormality
b) Intraoperative factor: diseased donor, DJ stent, prolong urethral catheter
c) Postoperative: acute allograft rejection, excessive immunosuppressive drug use
Aim of the study
Method
Results and Discussion
Limitation of the study
Strength of the study
Conclusion
Urinary tract infection is the most common infection after kidney transplantation, and common risk factor like female sex, age, and hyperglycemia are common. The used of TMX as prophylaxis appears not to play any significant role in reducing the incidence of UTIs among kidney transplantation patients
The level of evidence is 3
Hi Dr Abiola,
What is your reason for allocating level 3 to this report? I like your summary and analysis.
I appreciate that you have written strengths and limitations.