Impact of urinary tract infections on short-term kidney graft outcome

Clostridioides difficile Infection in Kidney Transplant Recipients

Clostridioides difficile (C. difficile) is a bacterial organism that typically infects the colon, which has had its homeostasis of healthy gut microbiota disrupted by antibiotics or other interventions. Patients with kidney transplantation are a group that are susceptible to C. difficile infection (CDI) and have poorer outcomes with CDI given that they conventionally require long-term immunosuppression to minimize their risk of graft rejection, weakening their responses to infection. Recognizing the risk factors and complex pathophysiological processes that exist between immunosuppression, dysbiosis, and CDI is important when making crucial clinical decisions surrounding the management of this vulnerable patient cohort. Despite the clinical importance of this topic, there are few studies that have evaluated CDI in the context of kidney transplant recipients and other solid organ transplant populations. The current recommendations on CDI management in kidney transplant and solid organ transplant recipients are mostly extrapolated from data relating to CDI management in the general population. We provide a narrative review that discusses the available evidence examining CDI in solid organ transplant recipients, with a particular focus on the kidney transplant recipient, from the epidemiology of CDI, clinical features and implications of CDI, potential risk factors of CDI, and, ultimately, prevention and management strategies for CDI, with the aim of providing areas for future research development in this topic area.

Prevalence and risk factors of urinary tract infection in kidney recipients: a meta-analysis study

BACKGROUND

A kidney recipient's urinary tract infection (UTI) can result in infectious problems and be a risk factor for less successful transplant outcomes. UTI risk factors are still controversial. The present study aimed to investigate the prevalence of UTI and its association with risk factors in kidney recipients.

METHOD

Twenty-six papers published between 2005 and 2022 were retrieved using keywords and searching Medlib, ScienceDirect, PubMed, and other databases. If possible, the pooled prevalence of UTI in kidney recipients and odds ratio (OR) with a 95% confidence interval for each risk factor were calculated. The data were analyzed using the random effects model in R and Stata 14.

RESULTS

The total sample size was 72,600, with an average age of 48.7 years. The pooled prevalence of UTI was 35% (95% CI, 30-40%). The estimated risk factors for UTI were female (OR = 3.13; 95%CI: 2.35-4.17), older age (OR = 1.03; 95%CI: 1-1.05), history of UTI (OR = 1.31; 95%CI) CI: 1.05-1.63), receiving a kidney from a deceased donor (OR = 1.59; 95%CI: 1.23-2.35), long-term use of an indwelling catheter (OR = 3.03; 95%CI: 1.59-6.59), a ureteral stent (OR = 1.54; 95%CI: 1.16-2.06), diabetes (OR = 1.17; 95%CI: 0.97-1.41), hypertension (OR = 1.6; 95%CI: 1.26-2.28), acute rejection process (OR = 2.22; 95%CI: 1.45-3.4), and abnormal urinary tract anatomy (OR = 2.87; 95%CI 1.44-5.74).

CONCLUSION

This meta-analysis revealed that UTIs are a significant problem in kidney recipients. Factors such as female sex, old age, history of UTIs, deceased donor, long-term use of an indwelling catheter, diabetes, acute rejection process, use of ureteral stent, abnormal urinary tract anatomy, and hypertension were related to an increased risk of UTIs in kidney recipients.

The Impact of Urinary Tract Infections in Kidney Transplant Recipients: A Six-Year Single-Center Experience

Background Urinary tract infections (UTIs) are the most common infections following kidney transplantation. Risk factors for UTIs in kidney transplant recipients include female gender, age, pre-transplant urinary tract abnormalities, diabetes, and recurrent UTIs. Infections of the bladder or urethra are termed lower UTIs, while those involving the kidneys or ureters are called upper UTIs. Methods We retrospectively screened our hospital information system to identify all patients who underwent kidney transplantation in the surgery department at King Abdulaziz Medical Center in Riyadh. A total of 553 records were ultimately included in the final analysis. Results A total of 553 patients were ultimately included in the analysis. More than half of the patients were males (62.4%), and 31.1% were aged between 45 and 60 years. Of these, 230 patients had a UTI, representing 41.59% of the sample. The most commonly reported causes were hypertensive nephrosclerosis (43.4%) and diabetic nephropathy (28.8%). The most frequently isolated causative agents were Escherichia coli (51.0%) and Klebsiella pneumoniae (21.8%). UTIs were significantly more prevalent among females, accounting for 73.6% of cases. Antibiotics were used in 86.5% of patients, with trimethoprim/sulfamethoxazole (65.8%) and ciprofloxacin (54.8%) being the most commonly prescribed. Conclusion About half of the patients in this study suffered from UTIs. E. coli and K. pneumoniae were the most commonly isolated organisms. Trimethoprim/sulfamethoxazole and ciprofloxacin were the most frequently prescribed antibiotics. A significant association was found between acquiring a UTI and being female (p < 0.001), as well as having pre-existing bladder dysfunction (p = 0.024).

Asymptomatic Bacteriuria in Kidney Transplant Recipients-A Narrative Review

Urinary tract infections (UTIs) are the most prevalent complications in kidney transplant (KTx) recipients. The most frequent finding in this group of patients is asymptomatic bacteriuria (ASB). Here, we provide an overview of the available evidence regarding ASB in KTx recipients, including its etiopathology, clinical impact and management. There is a growing body of evidence from clinical trials that screening for and treating ASB is not beneficial in most KTx recipients. However, there are insufficient data to recommend or discourage the use of a "screen-and-treat strategy" for ASB during the first 1-2 months post-transplant or in the case of an indwelling urinary catheter. Despite its frequency, ASB after KTx is still an understudied phenomenon.

Recurrent Urinary Tract Infection in Living Donor Renal Transplant Recipients and the Role of Behavioral Education Program in Management: A Single-Center Experience

BACKGROUND

Urinary tract infections (UTIs) are the most prevalent type of kidney transplant (KT) recipients. We aimed to investigate the incidence, causes, and clinical impact of early recurrent UTI post-living donor KT and to examine the role of behavioral education program in management.

METHODS

This retrospective cohort chart-review study included all KT recipients with recurrent UTI necessitating hospital admission between September 2017 and August 2021. All patients with recurrent UTI were subjected to behavioral education for a month.

RESULTS

UTI was found in 14 of 145 patients (9.6%), with recurrent UTI in 11 (7.6%). A total of 93% of UTIs occurred during the first 6 months post-transplant and represented 52% of KT readmissions during the same period. A total of 64.3% of patients were older than 50 years. The mean (SD) length of hospital stay was 5 (2.5) days, with an equal incidence in both sexes. The most common bacterial isolates in early recurrent UTI were Escherichia coli in 80.9%. Both Extended-spectrum beta-lactamases and multidrug-resistant organisms (resistance in ≥3 drugs) were seen in 82.4% of isolates. Furthermore, the most effective antibiotic was meropenem, with 86.7% effectiveness. A total of 65% of UTIs were managed with a single antibacterial course. A total of 64.3% of patients were older than 50 years. In patients who developed UTI, the mean (SD) serum creatinine was 1.31 (0.52) mg/dL, with a mean increase in serum creatinine of 0.19 mg/dL on having the episodes; at 1 year post-transplant, serum creatinine declined to 1.23 (0.43) mg/dL. Four patients (36%) had no recurrence of UTI after behavioral education.

CONCLUSIONS

The multidrug-resistant bacterial isolates account for 82.4% of the UTIs. Therefore, antibiotic prescription should follow the antimicrobial stewardship guidelines. Behavioral education significantly reduced the incidence of recurrent UTI.

Bacterial Urinary Tract Infection and Early Asymptomatic Bacteriuria in Kidney Transplantation Still Negatively Affect Kidney Transplant Outcomes in the Era of Modern Immunosuppression and Cotrimoxazole Prophylaxis

Risk factors and consequences of urinary tract infection (UTI) post-kidney transplant have been variously reported by studies that were heterogenous in immunosuppressants and prophylactic protocols. We aimed to clarify the risks and consequences of UTI in kidney transplant recipients with post-transplantation cotrimoxazole prophylaxis in the context of modern immunosuppression. This retrospective cohort included kidney transplant recipients receiving tacrolimus, mycophenolate, prednisolone, and cotrimoxazole for bacterial UTI prophylaxis. Recipients were categorized into non-UTI and UTI groups. Asymptomatic bacteriuria (ASB) was screened in the first 3 months and was evaluated for association with UTI. Of 348 kidney transplant recipients, 129 were in the UTI group and 219 in the non-UTI group. UTI risk factors were female sex, body mass index ≥ 25 kg/m², human leukocyte antigen mismatch, and panel reactive antibody ≥ 50%. Recipients with recurrent UTI had inferior allograft function compared with non-UTI recipients. Patient survival was significantly lower in recipients with UTI in the first post-transplant month. Higher degree of immunosuppressions was associated with recurrent UTI and drug-resistant organisms. In conclusion, UTI continues to negatively affect graft function and survival of kidney transplant recipients. Treating ASB in the first 3 months did not reduce the UTI incidence in the first transplantation year.

Predictors of Short-Term Outcomes in Living Donor Renal Allograft Recipients: A Prospective Study From a Tertiary Care Center in North India

Background

Renal transplantation is the optimal treatment for patients of all ages with end-stage kidney disease. The long-term outcomes of renal transplantation are assessed by graft and patient survival rates. These outcomes are, in turn, influenced by post-transplant events such as delayed graft function, rejections, post-transplant infections, and post-transplant diabetes mellitus (PTDM). Each of these short-term outcomes is, in turn, determined by the interplay of various factors in the pre-, peri-, and post-transplant period. This prospective study was designed to understand the factors affecting short-term outcomes in living donor transplantation and their effect on graft and patient survival.

Methodology

A total of 86 patients underwent live donor renal transplantation between January 1, 2015, and March 31, 2016, at a tertiary care hospital in north India. Of these, five were lost to follow-up, and the remaining 81 patients were prospectively followed up to December 31, 2017.

Results

The majority of the recipients were males (91%) and the donors were females (74%). Spousal and related donors comprised 49% and 51% of donations, respectively. The mean estimated glomerular filtration rate (eGFR) of donors was 98 ± 9.2 mL/minute/1.73m². Induction therapy with basiliximab was given to 21/81 (26%) recipients. The majority of recipients (68/81, 84%) received triple-drug immunosuppression with prednisolone, tacrolimus, and mycophenolate mofetil. Delayed graft function (DGF) occurred in 4/81 (4.9%) cases. Biopsy-proven acute rejections (BPARs) occurred in 15/81 (18.5%) cases, two-thirds of which were acute antibody-mediated rejections (ABMRs). During the follow-up period, 50 episodes of infections occurred in 35/81 (43.2%) recipients, with the most common being urinary tract infection (23/81, 28.5%). PTDM was diagnosed in 22/81 (27.2%) patients beyond six weeks of transplant. On multivariate logistic regression analysis, the most significant predictor of DGF was acute rejections and vice versa. Acute rejections also predicted the occurrence of post-transplant infections. Pre-transplant hepatitis C virus (HCV) infection and cyclosporine-based therapy were significant predictors of PTDM. At the six-month follow-up, 10/81 (12.3%) patients developed graft dysfunction. The predictors of graft dysfunction at six months were recipients of related donors and rural patients. One-year graft survival, death-censored graft survival, and patient survival rates were 85.2%, 92.6%, and 91.3%, respectively. The most common cause of death was post-transplant infections (5/7, 71.4%) of which the majority (4/5, 80%) were fungal infections. On multivariate logistic regression analysis, the most significant predictor of graft loss and patient loss was low pre-transplant donor eGFR and PTDM, respectively.

Conclusions

Graft and patient survival in living donor kidney transplantation are influenced by a multitude of interdependent factors during the pre-transplant (donor eGFR, type of donor, socioeconomic status, HCV infection in recipient, type of immunosuppression) and the post-transplant (DGF, rejections, infections, and PTDM) period.

Acute kidney injury secondary to urinary tract infection in kidney transplant recipients

Acute kidney injury (AKI) in kidney transplant recipients (KTRs) is a common, yet poorly investigated, complication of urinary tract infections (UTI) and urosepsis. A retrospective comparative analysis was performed, recruiting 101 KTRs with urosepsis, 100 KTRs with UTI, and 100 KTRs without history of UTI or sepsis. The incidences of AKI in the urosepsis and UTI groups were 75.2% and 41%, respectively. The urosepsis group has also presented with a significantly higher prevalence of AKI stage 2 and 3 than the UTI group. The rates of recovery from AKI stages 1, 2 and 3, were 75,6%, 55% and 26.1%, respectively. Factors independently associated with renal recovery from AKI were: AKI severity grade (AKI stage 2 with OR = 0.25 and AKI stage 3 with OR = 0.1), transfusion of red blood cells (RBC) (OR = 0.22), and the use of steroid bolus in the acute phase of treatment (OR = 4). The septic status (urosepsis vs UTI) did not influence the rates of renal recovery from AKI after adjustment for the remaining variables. The dominant cause of RBC transfusions in the whole population was upper GI-bleeding. In multivariable analyses, the occurrence of AKI was also independently associated with a greater decline of eGFR at 1-year post-discharge and with a greater risk of graft loss. In KTRs with both urosepsis and UTI, the occurrence of AKI portends poor transplantation outcomes. The local transfusion policy, modulation of immunosuppression and stress ulcer prophylaxis (which is not routinely administered in KTRs) in the acute setting may be modifiable factors that significantly impact long-term transplantation outcomes.

Retrospective Analysis of the Risk Factors of Perioperative Bacterial Infection and Correlation with Clinical Prognosis in Kidney Transplant Recipients

Background

Infection remains a leading cause of morbidity and mortality in kidney transplant patients. This study aimed to investigate the risk factors of bacterial infection during the perioperative period of transplantation and the effects of infection on long-term clinical outcomes.

Methods

In total, 295 kidney transplantation recipients were included in this retrospective study and assigned to two groups: non-infected and infected. The tacrolimus concentration, pharmacogenomics, laboratory parameters, and clinical outcomes of both groups were evaluated.

Results

A relatively low incidence of urinary tract infection was observed in our cohort, and lung was identified as the most frequent site of infection. Gram-negative bacteria, such as Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae, were the most common infecting strains in kidney transplant recipients. Patients with diabetes showed greater susceptibility to infection. Compared with the non-infected group, tacrolimus concentration was significantly lower on day 7 and 14 in the infected group. White blood cell count, neutrophil count, and C-reactive protein (CRP) in the infected group were markedly higher post-transplantation, while albumin levels were lower relative to the non-infected group. ABCB1 (rs2032582) genotype showed clear associations with infection. Furthermore, the incidence of delayed graft function (DGF) and early acute rejection (AR) before infection was significantly greater in the infected group. Finally, early post-transplant infection was associated with a marked increase in the incidence of AR, post-transplant diabetes mellitus (PTDM), and secondary infection.

Conclusion

Pre-diabetes, longer duration of catheterization, lower albumin, higher CRP, tacrolimus concentration on the day 7 and 14, early AR before infection, and DGF were closely related to postoperative infection in kidney transplantation recipients. Moreover, bacterial infection during the perioperative period was closely associated with AR, PTDM and secondary infection.

Urinary Tract Infections in Kidney Transplant Recipients-Is There a Need for Antibiotic Stewardship?

(1) Background: Urinary tract infections (UTI) are the most common infections after kidney transplantation. Given the risk of urosepsis and the potential threat to the graft, the threshold for treating UTI and asymptomatic bacteriuria with broad spectrum antibiotics is low. Historically fluoroquinolones were prescription favorites for patients that underwent kidney transplantation (KT). After the recent recommendation to avoid them in these patients, however, alternative treatment strategies need to be investigated (2) Methods: We retrospectively analyzed the charts of 207 consecutive adult kidney transplantations that were performed at the department of General, Visceral and Transplantation Surgery of the University Hospital of Tuebingen between January 2015 and August 2020. All charts were screened for the diagnosis and treatment of asymptomatic bacteriuria (ASB) and urinary tract infections (UTI) and the patients' clinical characteristics and outcomes were evaluated. (3) Results: Of the 207 patients, 68 patients suffered from urinary tract infections. Patients who developed UTI had worse graft function at discharge (p = 0.024) and at the 12 months follow-up (p < 0.001). The most commonly prescribed antibiotics were Ciprofloxacin and Piperacillin/Tazobactam. To both, bacterial resistance was more common in the study cohort than in the control group. (4) Conclusions: Urinary tract infections appear to be linked to worse graft functions. Thus, prevention and treatment should be accompanied by antibiotic stewardship teams.

Caracterización de la infección urinaria y resistencia antimicrobiana en receptores de trasplante renal de un centro colombiano

La infección del tracto urinario (ITU) es una de las principales complicaciones postrasplante renal, los datos a nivel nacional en ese grupo poblacional son limitados.

Objetivos caracterizar la microbiología de las ITU presentadas en receptores de trasplante renal (TxR) en un centro colombiano durante el periodo 2017–2019, los factores relacionados con la resistencia antimicrobiana y el impacto de la ITU en la función del injerto renal.

Métodos estudio de corte transversal ejecutado mediante el análisis de la base de datos de ingresos hospitalarios por urgencias de pacientes receptores de TxR con sospecha clínica de ITU en una institución de cuarto nivel en Bogotá, Colombia. El análisis de datos se ejecutó en STATA 13.0.

Resultados La ITU causó 12,69% de visitas a urgencias en pacientes trasplantados. Los microorganismos aislados fueron: Escherichia coli 52,22%, Klebsiella pneumoniae 16,67%, Pseudomonas aeruginosa 4,44%, Salmonella spp 4,44%, Proteus mirabilis 3,33%, Serratia marcescens 2,22%, Klebsiella oxytoca 2,22%, Citrobacter koseri 1,11%, Enterobacter cloacae 1,11%, otros 2,22%; El urocultivo fue negativo en 10% de los casos. El 28,39% (n:23) de gérmenes aislados fue multisensible mientras que el 71,60% (n:58) expresó algún tipo de patrón de resistencia distribuido así: 68,96% productor de betalactamasa de espectro extendido (BLEE), 15,52% productor de carbapenemasas, 12,06% productor de betalactamasa tipo IRT, 3,45% fue catalogado como multirresistente. 17,78% de los pacientes presentó criterios de urosepsis, no se registró ningún caso de mortalidad asociada a la ITU. La creatinina sérica tuvo un incremento promedio de 0,46 mg/dl durante el episodio de ITU (p: <0,0001) y el antecedente de diabetes mellitus se relacionó con la ITU causada por gérmenes resistentes (p: 0,008).

Conclusiones La ITU es una causa frecuente de atención en urgencias para pacientes receptores de TxR; la Escherichia coli es el microorganismo causal más frecuente y cerca del 70% de los gérmenes aislados presentó algún patrón de resistencia antimicrobiana.

A Current Review of the Etiology, Clinical Features, and Diagnosis of Urinary Tract Infection in Renal Transplant Patients

Urinary tract infection (UTI) represents the most common infection after kidney transplantation and remains a major cause of morbidity and mortality in kidney transplant (KT) recipients, with a potential impact on graft survival. UTIs after KT are usually caused by Gram-negative microorganisms. Other pathogens which are uncommon in the general population should be considered in KT patients, especially BK virus since an early diagnosis is necessary to improve the prognosis. UTIs following kidney transplantation are classified into acute simple cystitis, acute pyelonephritis/complicated UTI, and recurrent UTI, due to their different clinical presentation, prognosis, and management. Asymptomatic bacteriuria (ASB) represents a frequent finding after kidney transplantation, but ASB is considered to be a separate entity apart from UTI since it is not necessarily a disease state. In fact, current guidelines do not recommend routine screening and treatment of ASB in KT patients, since a beneficial effect has not been shown. Harmful effects such as the development of multidrug-resistant (MDR) bacteria and a higher incidence of Clostridium difficile diarrhea have been associated with the antibiotic treatment of ASB.

Outcome of a thorough screening of lower urinary tract function in all pediatric kidney recipients

LUTD is one of the possible factors influencing pediatric kidney graft outcomes. This study evaluates the results of a thorough assessment of voiding behavior in pediatric transplants. Data of patients with kidney disease of nephrological origin are compared to those with urological origin. A single-center analysis of pediatric kidney transplants performed from 2005 to the present was executed. Donor and recipient characteristics as well as voiding and drinking habits were documented using FVCs and uroflowmetry with PVR measurements. LUTD was defined by a mean MVV >150% or <65% of the EBC for age, abnormal uroflowmetry, PVR repeatedly >15% of EBC or >20 mL, abnormal voiding patterns or behavior, and presence of LUT symptoms. LUTD was diagnosed in 71% of the 56 screened children and more present in urological origin of kidney disease (100%) compared to nephrological origin (61%, P = .005). Individual presence of LUT symptoms, abnormal voiding behavior, FVC parameters, UTIs, and uroflowmetry/PVR parameters were not different between the two groups. Polyuria after transplantation was seen in 63% of patients, mainly in the first post-transplant years and recipients aged <10 years. Time after transplantation was a significant independent predictive factor for the presence of LUTD. LUTD is common in all pediatric kidney recipients and underestimated in those with a nephrological origin of disease. Active screening, monitoring and a care attention plan prior to transplantation and during follow-up, is advocated to optimize outcomes for all patients.

Incidence and risk factors for urinary tract infections in the first year after renal transplantation

Background

The most common infections among renal transplant patients are urinary tract infections (UTI). Our main objective in this study is to determine the incidence of UTIs in patients who have undergone renal transplantation in our hospital, to identify the causative microbiological agents, risk factors and determine the effects of UTI on short-term graft survival.

Methods

Urinary tract infections, which developed within the first year of renal transplantation, were investigated. Patients were compared regarding demographic, clinical, laboratory characteristics and graft survival.

Results

102 patients were included in our study. Fifty-three patients (53%) were male and 49 (48%) were female. Sixty-seven urinary tract infection attacks in 21 patients (20.5%) were recorded. Age (p = 0.004; 95% Confidence Interval [CI]: 1.032–1.184), longer indwelling urinary catheter stay time (p = 0.039; 95% Confidence Interval [CI]: 1.013–1.661) and urologic complications (p = 0.006; 95% Confidence Interval [CI]: 0.001–0.320) were found as risk factors for UTI development in the first year of transplantation. Escherichia coli and Klebsiella pneumoniae were the most frequently isolated microorganisms. Of these bacteria, 63.2% were found to be extended spectrum beta lactamase (ESBL) positive. Multidrug resistant microorganisms (MDROs) were more frequent in male patients (32 episodes in males vs. 14 episodes in females, p = <0.001). UTI had no negative impact on short-term graft survival.

Conclusion

Our study results represent the high incidence of UTI with MDROs in KT recipients. Infection control methods should be applied even more vigorously especially in male transplant patients since a higher incidence of UTI caused by resistant microorganisms was reported in male patients.

Efficacy and safety of oral fosfomycin for asymptomatic bacteriuria in kidney transplant recipients: Results from a Spanish multicenter cohort

Current guidelines recommend against systematic screening or treating asymptomatic bacteriuria (AB) among kidney transplant (KT) recipients, although the evidence regarding episodes occurring early after transplantation or in the presence of anatomical abnormalities is inconclusive. Oral fosfomycin may constitute a good option for the treatment of post-transplant AB, particularly due to the emergence of multidrug-resistant (MDR) uropathogens. Available clinical evidence supporting its use in this specific setting, however, remains scarce. We performed a retrospective study in 14 Spanish institutions from January 2005 to December 2017. Overall, 137 episodes of AB diagnosed in 133 KT recipients treated with oral fosfomycin (calcium and trometamol salts) with a test-of-cure urine culture within the first 30 days were included. Median time from transplantation to diagnosis was 3.1 months (interquartile range [IQR]: 1.1 - 10.5). Most episodes (96.4% [132/137]) were caused by gram-negative bacteria (GNB), and 56.9% (78/137) were categorized as MDR (extended-spectrum β-lactamase-producing Enterobacterales [20.4%] and carbapenem-resistant GNB [2.9%]). Rate of microbiological failure at month 1 was 40.1% (95% confidence interval [95%CI]: 31.9 - 48.9) for the whole cohort and 42.3% (95%CI: 31.2 - 54.0) for episodes due to MDR pathogens. Previous urinary tract infection (odds ratio [OR]: 2.42; 95%CI: 1.11 - 5.29; P-value = 0.027) and use of fosfomycin as salvage therapy (OR: 8.31; 95%CI: 1.67 - 41.35; P-value = 0.010) were predictors of microbiological failure. No severe treatment-related adverse event were detected. Oral fosfomycin appears to be a suitable and safe alternative for the treatment (if indicated) of AB after KT, including those episodes due to MDR uropathogens.

Overview on urinary tract infection, bacterial agents, and antibiotic resistance pattern in renal transplant recipients

Background:

Urinary tract infection (UTI) is a mainly common infection in kidney transplant recipients. This study decided to investigate UTI, bacterial agents, and antibiotic resistance pattern in kidney transplant recipients from Iran.

Materials and Methods:

Search process was conducted for UTI, bacterial agents, and antibiotic resistance pattern in kidney transplant recipients from Iran via electronic databases (Scopus, PubMed, Web of Science, etc.,) with Mesh terms in either Persian and English languages without limited time to May 31, 2020. Data were analyzed by comprehensive meta-analysis software.

Results:

The combined prevalence of UTI in renal transplant recipients was reported by 31.1%. The combined prevalence of Gram-negative bacteria was 69%. The most common pathogens among Gram negatives were E. coli followed by Klebsiella pneumoniae with frequency 43.4% and 13%, respectively. Subgroup analysis for Gram-positive bacteria showed the combined prevalence of 31%. The most common microorganism among Gram positives belonged to coagulase-negative Staphylococci and Enterococci with a prevalence of 10.2% and 9%, respectively. Subgroup meta-analysis of antibiotic resistance for Gram-negative showed the most resistance to cephalexin followed by carbenicillin with a prevalence of 89.1% and 87.3%, respectively.

Conclusion:

Our review showed a noticeable rate of UTI (31.1%) among renal transplant recipients in Iran and a high prevalence of Gram-negative (69%) and Gram-positive (13%) microorganisms. A high resistance rate was seen against almost all antibiotics used for the treatment of UTI. Therefore, empirical prescription of antibiotics should be avoided, and it should be based on data obtained from antibiogram tests.

Analysis of risk factors for early urinary tract infection after kidney transplantation

Background

Urinary tract infection (UTI) is the most common kind of infection in the early stage after kidney transplantation. Although many studies have investigated the risk factors for UTI following kidney transplantation, few studies have focused on the risk factors for UTI in the early stage after transplantation.

Methods

The early-stage data of patients who underwent kidney transplantation between January 2018 and December 2019 in a first-class tertiary hospital in Suzhou, China, were retrospectively analyzed. The general and UTI information of the recipients was subjected to univariate analysis. Variables with statistical significance in the univariate analysis were included in a multivariate logistic regression model.

Results

A total of 129 recipients were recruited, among whom 62 patients had a UTI in the early stage after kidney transplantation (48.1%), and the median (interquartile range) of onset time was 5 (4, 10) days after the surgery. A total of 324 strains of UTI pathogens were detected in the 62 recipients after kidney transplantation, 279 of which were gram-negative bacilli (86.1%). Multivariate logistic regression analysis showed that female sex and delayed graft function (DGF) were independent risk factors for early-stage UTI, with odds ratios of 0.095 and 3.753, respectively.

Conclusions

The incidence of early UTI after kidney transplantation is high. Females and DGF patients are more prone to UTIs. Comprehensive prevention and treatment measures should be taken as early as possible against the risk factors to reduce the incidence of UTI.

Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America

Asymptomatic bacteriuria (ASB) is a common finding in many populations, including healthy women and persons with underlying urologic abnormalities. The 2005 guideline from the Infectious Diseases Society of America recommended that ASB should be screened for and treated only in pregnant women or in an individual prior to undergoing invasive urologic procedures. Treatment was not recommended for healthy women; older women or men; or persons with diabetes, indwelling catheters, or spinal cord injury. The guideline did not address children and some adult populations, including patients with neutropenia, solid organ transplants, and nonurologic surgery. In the years since the publication of the guideline, further information relevant to ASB has become available. In addition, antimicrobial treatment of ASB has been recognized as an important contributor to inappropriate antimicrobial use, which promotes emergence of antimicrobial resistance. The current guideline updates the recommendations of the 2005 guideline, includes new recommendations for populations not previously addressed, and, where relevant, addresses the interpretation of nonlocalizing clinical symptoms in populations with a high prevalence of ASB.

Five compelling UTI questions after kidney transplant

PURPOSE

Urinary tract infection (UTI) is the most common bacterial infection among infectious complications in kidney transplant recipients (KTR). After transplantation, infections can result from surgical complications, donor-derived infections, pre-existing recipient infections, and nosocomial infections. Post-transplant infection is still a major cause of morbidity, mortality, graft dysfunction and rejection. In this paper, we aimed to review a few compelling questions in kidney transplantation (KTX).

METHODS

To identify relevant clinical questions regarding KTX and UTI a meeting was conducted among physicians involved in the KT program in our hospital. After discussion, several clinically relevant questions related to UTI after KTX. The 5 first rated in importance were judged generalizable to other clinical settings and selected for the purposes of this review.

RESULTS

Nearly half of the patients present in the first three months of transplant with UTI. The most common uropathogens in post-transplant UTIs are Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. Risk factors for UTI include female sex, advanced age, recurrent UTI before transplant, prolonged urethral catheterization, delayed graft function, and cadaveric kidney transplant.

CONCLUSION

The incidence of post-transplant UTI is similar in both developed and developing countries. E.coli is the most common pathogen in most of studies. Cadaveric donor and post-dialysis transplantation are defined as independent risk factors for post-transplant UTI. Further studies are still required to identify risk factors after kidney transplantation and UTI's importance for graft function and patient outcome.

Lack of Impact of Acute Pyelonephritis on Kidney Graft Survival

BACKGROUND

Urinary tract infection is the most common bacterial infection after kidney transplant. Some studies suggested that urinary tract infection could impair graft survival, but this issue remains debated. The objective of this study was to analyze the association between acute pyelonephritis (APN) and the risk of kidney graft failure.

METHODS

We performed a retrospective cohort study including patients who received a kidney transplant from 2001 to 2009 at a university hospital in Rio de Janeiro, Brazil. They were followed until December 2015. The primary outcome was graft failure. Follow-up of patients who died with a functioning graft was censored on the date of death. Cox proportional hazards method was used in multivariable analysis to assess risk factors for graft failure. The occurrence of the first episode of APN and acute rejection were modeled as time-dependent variables.

RESULTS

A total of 587 patients were included. Of these, 112 recipients (19%) developed 173 episodes of APN. Graft failure occurred in 150 patients (25%) after a median follow-up of 79 months. The factors associated with graft failure in the multivariate analyses were age of the transplant recipient (hazard ratio [HR], 0.97 per year; 95% confidence interval [CI], 0.96-0.99; P < .01), occurrence of delayed graft function (HR, 2.42; 95% CI, 1.72-3.40; P < .01), and acute rejection (HR, 2.71; 95% CI, 1.92-3.82; P < .01). There was no association between APN and graft failure (HR, 1.05; 95% CI, 0.65-1.68; P = .85).

CONCLUSIONS

Our results suggest that the occurrence of APN is not associated with a significant reduction in graft survival after kidney transplant.

Systematic review and meta-analysis of asymptomatic bacteriuria after renal transplantation: incidence, risk of complications, and treatment outcomes

BACKGROUND

Routine treatment for asymptomatic bacteriuria (ASB) after renal transplantation (RT) represents nowadays a controversial topic, being unknown its impact on the overall prognosis of the transplanted patient.

METHODS

Studies published during 1970-2019 that evaluated the benefit of treating ASB after RT regarding the risk of renal complications were included. The primary outcome was to assess whether the treatment is associated with a lower risk of symptomatic urinary tract infection (UTI) or an improved renal function at the end of the follow-up period. The secondary outcome was the risk of acute graft rejection (AGR). A meta-analysis with a random-effect model was performed. Heterogeneity was assessed with the I² measure.

RESULTS

Fifteen studies were included. The incidence of ASB in the first month and the first year after RT was 22% and 30%, respectively. ASB was not correlated to AGR (OR 1.18; 95% CI, 0.78-1.79). Eight studies compared the outcomes of ASB treatment, finding no benefit of treating regarding the risk of symptomatic UTI (OR 1.08; 95% CI, 0.63-1.84; I²  = 35%) or the change in renal function (mean difference in serum creatinine concentration-0.03 mg/dL,95% CI-0.15-0.10; I²  = 53%).

CONCLUSIONS

Asymptomatic bacteriuria represents a frequent finding after RT, highlighting the need for appropriate management of this condition. Considering that its treatment did not decrease the risk of the studied complications, antibiotic therapy should start to be questioned, as it has been related to higher rates of antimicrobial resistance and high economic costs.

Microbiological epidemiology of preservation fluids in transplanted kidney: a nationwide retrospective observational study

OBJECTIVES

Kidney transplant recipients are at high-risk for donor-derived infections in the early post-transplant period. Transplant preservation fluid (PF) samples are collected for microbiological analysis. In case of positive PF cultures, the risk for the recipient is unknown and there is no consensus for prescribing prophylactic antibiotics. This nationwide observational study aimed to determine the epidemiology of bacterial and fungal agents in kidney transplant PF cultures and identify risk factors associated with positive PF cultures.

METHODS

We performed a retrospective observational study on the following data collected from a national database between October 2015 and December 2016: characteristics of donor, recipient, transplantation, infection in donor and PF microbiological data.

RESULTS

Of 4487 kidney transplant procedures, including 725 (16.2%, 725/4487) from living donors, 20.5% had positive PF cultures (living donors: 1.8%, 13/725; deceased donors: 24.1%, 907/3762). Polymicrobial contamination was found in 59.9% (485/810) of positive PF cultures. Coagulase-negative staphylococci (65.8%, 533/810) and Enterobacteriaceae (28.0%, 227/810) were the most common microorganisms. Factors associated with an increased risk of positive PF cultures in multivariable analysis were (for deceased-donor kidney transplants): intestinal perforation during procurement (OR 4.4, 95% CI 2.1-9.1), multiorgan procurement (OR 1.4, 95% CI 1.1-1.7) and en bloc transplantation (OR 2.5, 95% CI 1.3-4.9). Use of perfusion pump and donor antibiotic therapy were associated with a lower risk of positive PF cultures (OR 0.4, 95% CI 0.3-0.5 and OR 0.6, 95% CI 0.5-0.7, respectively).

CONCLUSION

In conclusion, 24% of deceased-donor PF cultures were positive, and PF contamination during procurement seemed to be the major cause.

Bacterial urinary tract infection among adult renal transplant recipients at St. Paul's hospital millennium medical college, Addis Ababa, Ethiopia

BACKGROUND

Despite significant advances in surgical techniques, immunosuppression protocols, follow up periods and antimicrobial stewardship in modern medicine; post-renal transplantation urinary tract infection remained a major public health problem globally. This multiple serious squeals includes asymptomatic bacteriuria, cystitis and pyelonephritis. Among these, the bacterial origin of infection complications accounts for the most significant clinical, socio-economic impacts in many countries of the world. Therefore, the aim of the study was to investigate the prevalence of bacterial isolates that cause urinary tract infections, assess antibiotic susceptibility pattern among symptomatic and asymptomatic renal transplant recipients attending at St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia.

METHODS

A hospital-based cross-sectional study was conducted from December 2017 to August 2018 among 74 renal transplant recipients St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia. A first morning voided clean-catch mid-stream urine specimens were collected and 0.001 ml inoculated onto blood and MacConkey agar plates following the standard bacteriological protocols. It was incubated aerobically at 35-37 °C for 24-48 h. Cultural characteristics and series of biochemical tests were used for the identification of isolates to species level based on the standard bacteriological protocols.

RESULTS

A hospital-based cross-sectional study has shown that significant bacteriuria was found in 11/74 (14.9, 95% CI =8.2-24.7) patients. The prevalence among females 6/32 (18.75%) was higher among males 5/42 (11.9%) without significant association (COR = 2.09, 95% CI = 1.04-8.45, P = 0.253). Urinary tract infection was higher in the age group of 35-49 years old (19.3%). Age was statistically significant and stronger independent associated risk factor with crude odds ratio = 3.67, 95% CI = 2.89-20.07 and P = 0.003, respectively. The most prevalent bacteria isolates were Escherichia coli 2(18.2%), Staphylococcus aureus 2(18.2%), Acinetobacter spp. 2(18.2%), Enterococcus spp. 2(18.2%), Coagulase-negative Staphylococci 2(18.2%) followed by Porteus mirabilis 1(9.1%). The majority (80%) of Gram-negative bacteria were resistant to ciprofloxacin, chloramphenicol, and trimethoprim/sulfamethoxazole. Simultaneously, the multidrug-resistant bacterial isolates accounts for 82% among tested kidney allograft recipients.

CONCLUSIONS

In conclusion, the overall prevalence of urinary tract infection in the study participants was relatively low with a prevalence of 14.9%. Majority of the study participants were asymptomatic and a higher percentage of females were involved. The multidrug-resistant bacterial isolates in the present study account for 82%.

Perioperative prophylaxis with ertapenem reduced infections caused by extended-spectrum betalactamase-producting Enterobacteriaceae after kidney transplantation

Backgound

In recent years we have witnessed an increase in infections due to multidrug-resistant organisms in kidney transplant recipients (KTR). In our setting, we have observed a dramatic increase in infections caused by extended-spectrum betalactamase-producing (ESBL) Enterobacteriaceae in KTR. In 2014 we changed surgical prophylaxis from Cefazolin 2 g to Ertapenem 1 g.

Methods

We compared bacterial infections and their resistance phenotype during the first post-transplant month with an historical cohort collected during 2013 that had received Cefazolin.

Results

During the study period 110 patients received prophylaxis with Cefazolin and 113 with Ertapenem. In the Ertapenem cohort we observed a non-statistically significant decrease in the percentage of early bacterial infection from 57 to 47%, with urine being the most frequent source in both. The frequency of infections caused by Enterobacteriaceae spp. decreased from 64% in the Cefazolin cohort to 36% in the Ertapenem cohort (p = 0.005). In addition, percentage of ESBL-producing strains decreased from 21 to 8% of all Enterobacteriaceae isolated (p = 0.015). After adjusted in multivariate Cox regression analysis, male sex (HR 0.16, 95%CI: 0.03–0.75), cefazolin prophylaxis (HR 4.7, 95% CI: 1.1–22.6) and acute rejection (HR 14.5, 95% CI: 1.3–162) were associated to ESBL- producing Enterobacteriaceae infection.

Conclusions

Perioperative antimicrobial prophylaxis with a single dose of Ertapenem in kidney transplant recipients reduced the incidence of early infections due to ESBL-producing Enterobacteriaceae without increasing the incidence of other multidrug-resistant microorganisms or C. difficile.

Phenotypic and Genotypic Characterization of Escherichia coli Causing Urinary Tract Infections in Kidney-Transplanted Patients

Urinary tract infection (UTI), frequently caused by uropathogenic Escherichia coli (UPEC), is the most common infection after kidney transplantation (KTx). Untreated, it can lead to urosepsis and impairment of the graft function. We questioned whether the UPEC isolated from KTx patients differed from the UPEC of non-KTx patients. Therefore, we determined the genome sequences of 182 UPEC isolates from KTx and control patients in a large German university clinic and pheno- and genotypically compared these two isolated groups. Resistance to the β-lactams, trimethoprim or trimethoprim/sulfamethoxazole was significantly higher among UPEC from KTx than from control patients, whereas both the isolated groups were highly susceptible to fosfomycin. Accordingly, the gene content conferring resistance to β-lactams or trimethoprim, but also to aminoglycosides, was significantly higher in KTx than in control UPEC isolates. E. coli isolates from KTx patients more frequently presented with uncommon UPEC phylogroups expressing higher numbers of plasmid replicons, but interestingly, less UPEC virulence-associated genes than the control group. We conclude that there is no defining subset of virulence traits for UPEC from KTx patients. The clinical history and immunocompromised status of KTx patients enables E. coli strains with low uropathogenic potential, but with increased antibiotic resistance to cause UTIs.

Impact of asymptomatic bacteriuria incidence and management post-kidney transplantation

OBJECTIVE

Urinary tract infections (UTIs) are the most commonly occurring infectious complication following kidney transplantation. Questions remain regarding whether asymptomatic bacteriuria (ASB) should be treated. The aim was to evaluate the incidence and management of ASB in kidney transplant recipients at a large academic medical center.

METHODS

All subjects receiving an isolated kidney transplant between September 2012 and October 2016, and with at least one ASB episode were included. Demographics, symptomatology, and urine culture data were collected on subjects with bacteriuria in the first year post-transplant. Cultures were classified by symptoms, ASB treatment trends were analyzed, and ASB-to-UTI progression was compared between ASB treatment and non-treatment.

RESULTS

A total of 527 subjects were transplanted with 64 developing at least one ASB episode. The incidence of ASB was 12.1% and treated 74.6% of the time. Neither lack of ASB treatment (P = 0.463) nor ASB within the first month post-transplant (P = 0.303) were associated with ASB-to-UTI progression.

CONCLUSION

Despite high ASB treatment rate, this was not found to be protective against ASB-to-UTI progression. ASB within the first month post-transplant also did not correlate with increased progression risk. These results suggest minimization of ASB treatment in kidney transplant recipients remains an important antimicrobial stewardship target.

Host and pathogen factors in Klebsiella pneumoniae upper urinary tract infections in renal transplant patients

PURPOSE

To analyse the role of virulence factors (VFs) and host in Klebsiella pneumoniae upper urinary tract infections (UTIs) in renal transplant (RTx) recipients.

METHODOLOGY

Clinical and demographic data were registered prospectively. Phylogenetic background of K. pneumoniae isolates was analysed by PCR melting profiles (MP) and the following VFs genes: fimH-1, uge, kpn, ycfM, mrkD, rmpA, magA, hlyA, cnf-1, irp-1, irp-2, fyuA, entB, iutA, iroN by PCR.

RESULTS

We studied urine cultures and clinical data from 61 episodes of K. pneumoniae UTI in 54 RTx recipients. There were 32 cases of AB (53%), 10 cases of lower UTI (16%), 19 cases of AGPN (31%), including six cases of bacteraemia. In total, 74 % of strains were extended-spectrum beta-lactamase+, and there were two carbapenemase-producing strains. PCR MP typing showed a diverse population with 52 different genetic profiles of K. pneumoniae. Analysis of the DNA profiles indicated 45 unrelated, unique genotypes and 7 related (16 isolates from 15 patients) genotypes. Urine flow impairment emerged as an independent predictor of K. pneumoniae upper UTIs (OR 14.28, CI 2.7-75.56, P 0.002), while we did not find any association between the profile of VFs and developing upper UTIs. The prevalence of the uge gene was lower in RTx patients on everolimus when compared to isolates from patients not receiving mTOR inhibitors (33.3 % vs 82.8 % P<0.05).

CONCLUSIONS

K. pneumoniae upper UTI may be a marker of urine flow impairment. Bacterial VFs could not discriminate between upper and lower UTIs. However, immunosuppression may influence the selection of particular VFs.

Common Questions and Misconceptions in the Management of Renal Transplant Patients: A Guide for Health Care Providers in the Posttransplant Setting

Once renal transplant recipients are stabilized and require less frequent follow-up with their transplant team, health care providers outside of the transplant setting play an integral role in patients' ongoing medical care. Given renal transplant recipients' inherent complexity, these health care providers often seek consult regarding decisions that may affect transplant-related medications or outcomes. In this review, we discuss answers to 10 of the questions commonly posed to our renal transplant team by other health care providers.

Impact of Urinary Tract Infections in Kidney Transplant Recipients: A 4-Year Single-Center Experience

BACKGROUND

Urinary tract infection (UTI) is the most frequent bacterial infection in kidney transplant recipients (KTRs), yet little is known about the impact of severe UTIs. We aimed to explore the burden of severe UTIs post renal transplant on both graft function and health care resources.

METHODS

We conducted a retrospective review of KTRs with severe UTI warranting hospital admission at our center between January 1, 2012, and December 31, 2015.

RESULTS

We identified 198 UTI-related hospital admissions in 83 KTRs representing 7.4% of transplant admissions; 44.6% were men and 45 (54.2%) had recurrent admissions. The most commonly isolated pathogens were E coli (47.5%) and Klebsiella (16.2%): extended-spectrum β-lactamase-producing organisms were detected in 31.3% of Klebsiella and in 25.5% of E coli. During UTI, the median serum creatinine increased from 126 to 196.5 μmol/L, then decreased to 149 and 161 μmol/L 3 months and 1 year after UTI, respectively. Acute kidney injury complicated 40.9% of UTIs (23.7% stage 1, 12.1% stage 2, 5.1% stage 3), with no significant difference between single and recurrent admission groups (χ² = 0.36, P = .5). The 1-year mortality and death-censored graft loss were 1.2% and 3.6%, respectively. The median length of hospital stay was 4 days (286 days per annum) and the estimated annual cost was £87,665 ($117,347).

CONCLUSIONS

UTI post renal transplant represents a substantial burden on health care resources and patient morbidity in terms of acute kidney injury and deterioration in graft function. Thus, applying proper preventative and management strategies is paramount.

Managing recurrent urinary tract infections in kidney transplant patients

INTRODUCTION

Recurrent urinary tract infections (UTI) are a common clinical problem in kidney transplant recipients. Due to the complex urological anatomy derived from the implantation of the kidney graft, the spectrum of the disease and the broad underlying pathophysiological mechanisms. Recurrent UTI worsen the quality of life, decrease the graft survival and increase the costs of kidney transplantation. Areas covered: In this review, we describe the definitions, clinical characteristics, pathophysiological mechanisms and microbiology of recurrent urinary tract infections in kidney transplantations. The actual published literature on the management of recurrent urinary tract infections is based on case series, observational cohorts and very few clinical trials. In this review, the available evidence is compiled to propose evidence-based strategies to manage these complex cases. Expert commentary: The management of recurrent urinary tract infections in kidney transplant patients requires a proper diagnosis of the underlying mechanism. Early identification of structural or functional urological abnormalities, potentially amenable for surgical correction, is crucial for a successful management. The use of antibiotics to prevent recurrent infections should be carefully evaluated to avoid side effects and emergence of antibiotic-resistant microorganisms.

Epidemiology, risk factors, and impact of bacterial infections on outcomes for pancreatic grafts

We aimed to determine the epidemiology, risk factors, and impact of bacterial infection on pancreatic function after pancreas transplantation. Data for pancreas transplant recipients were retrospectively reviewed between 2000 and 2014 for at least 1 year. We collected and analyzed post-transplant data for bacterial infection, morbidity, and mortality. During the study period, 312 pancreas transplants were performed. In total, 509 episodes of bacterial infection were diagnosed in 191 patients (61%). Multidrug-resistant (MDR) organisms were present in 173 of the 513 isolated microorganisms (33%). Risk factors independently associated with bacterial infection were acute allograft rejection (OR 1.7, 95%CI 1.1-3), the need for post-transplant hemodialysis, (OR 5.3, 95%CI 1.8-15.7) and surgical re-intervention (OR 2.8, 95%CI 1.5-5.1), which was also considered a risk factor for infections caused by MDR bacteria. Graft survival was associated with the occurrence of one or more episodes of bacterial infection (log-rank test = 0.009). Surgical re-intervention was independently associated with graft loss (OR 2.5, 95%CI 1.3-4.7). To conclude, pancreas recipients frequently experienced bacterial infections associated with the need for hemodialysis or surgical re-intervention. Infection by MDR organisms is a growing concern in these patients and was related to graft survival. Graft loss was independently associated with surgical re-intervention.

Risk factors associated with Clostridium difficile infection in kidney transplant recipients

BACKGROUND

Solid organ transplant recipients are especially vulnerable to Clostridium difficile infection (CDI) due to cumulative risk factors including increased exposure to healthcare settings, persistent immunosuppression, and higher rates of antimicrobial exposure. We aimed to identify risk factors associated with CDI development in kidney transplant recipients including implications of immunosuppressive therapies and acid-suppressing agents.

METHODS

This was a single-center, non-interventional, retrospective case-control study of adult subjects between June 1, 2009 and June 30, 2013. During this time, 728 patients underwent kidney transplantation. Overall, 22 developed CDI (cases) and were matched 1:3 with 66 controls. Cases and controls were also matched for induction agent, kidney allograft type (living or deceased), and time from transplant to CDI result (±60 days).

RESULTS

The majority of subjects received a deceased donor kidney (77.3%) and basiliximab induction therapy (86.4%). The overall CDI incidence was 3%. Factors independently associated with CDI were average tacrolimus trough (AOR = 1.25, 95% CI = 1.00-1.56, P = .048) and antibiotic exposure for urinary tract infections (UTI) (AOR = 4.17, 95% CI = 1.12-15.54, P = .034). Proton pump inhibitor use was not associated with CDI (OR = 0.81, 95% CI = 0.29-2.29, P = .691).

CONCLUSION

Maintaining a clinically appropriate tacrolimus trough and judicious antibiotic use and selection for UTI treatment could potentially reduce CDI in the kidney transplant population.

Male kidney allograft recipients at risk for urinary tract infection?

Background

Urinary tract infection (UTI) is the most common infection after renal transplantation (RTx). Although female sex is a well-known risk factor for the development of UTI after RTx, the role of the donor sex in this context remains unclear.

Methods

In this case control study 6,763 RTx cases were screened for UTI when presenting at our transplant outpatient clinics. 102 different RTx patients fulfilled the inclusion criteria and were compared to 102 controls. Data on renal function was prospectively followed for 12 months. Results were compared to a previous RTx cohort from our transplant center. Additionally, we assessed the immunological response of leukocytes from 58 kidney recipients and 16 controls to lipopolysaccharide stimulation.

Result

After identification by univariate analysis, multivariate logistic regression analysis indicated female sex, minor height, advanced age and male kidney allograft sex to be associated with the occurrence of UTI after RTx. Female recipients who received male grafts had the best renal function 12 months after presentation. However, leukocyte response of recipients to lipopolysaccharide was impaired irrespective of donor and recipient sex to the same extend.

Conclusions

We conclude from our data that male kidney allografts are associated with the occurrence of UTI after RTx but did not influence the response of leukocytes to lipopolysaccharide. Further prospective studies are needed to identify the underlying mechanisms of higher male kidney donor dependent UTI.

Short-Term Outcome of Untreated Versus Treated Asymptomatic Bacteriuria in Renal Transplant Patients

BACKGROUND

Infection of the urinary tract (UTI) is the most common form of bacterial infection in renal transplant patients, but its management is still controversial. We compared symptomatic and asymptomatic bacteriuria, treated or untreated, during two different months (summer or winter).

METHODS

This longitudinal, prospective study involved routine urine cultures collected during September 2014 or March 2015. Demographic, clinical, and microbiological characteristics from the patients with positive urine cultures were described. The main outcomes were the need of hospitalization, the bacterial clearance, and the selection of the resistant pathogen.

RESULTS

From the 538 urine cultures collected, only 61 were positive urine cultures. Twenty were untreated asymptomatic bacteriuria (AB), 28 were treated AB, and 13 were treated symptomatic bacteriuria. The more prevalent micro-organisms were E coli (27%), K pneumoniae (11%), and E faecalis (7%). There were no differences in the demographic, clinical, and microbiological characteristics depending on the month when the urine cultures were collected. Only 10 patients required hospitalization during follow-up, and all of them belonged to the treated group. Bacterial clearance after the treatment occurred in 20 patients of the 41 treated (48.9%) and spontaneously in 14 of the 20 patients untreated (70%). Of the treated patients, 47.6% developed a new resistance to another antibiotic.

CONCLUSIONS

Only 7.6% of the routine urine cultures on renal transplant were positive. Untreated AB did not require hospitalization, and 70% had spontaneous bacterial clearance.

Increased resistance of gram-negative urinary pathogens after kidney transplantation

BACKGROUND

Urinary tract infection is the most common complication after kidney transplantation. It can cause severe sepsis and transplant loss. Emergence of drug resistance among gram-negative urinary pathogens is the current challenge for urinary tract infection treatment after kidney transplantation.

METHODS

This study analyzes the antimicrobial susceptibility of gram-negative urinary pathogens after kidney transplantation from 2009 to 2012 at the Transplant Outpatient Clinic of the University Hospital Essen, Germany. Kidney transplant patients at the University Hospital Essen receive regular follow up examinations after transplantation. Midstream urines were examined for bacteriuria at each follow up visit.

RESULTS

From 2009 to 2012 15.741 urine samples were obtained from 859 patients. In 2985 (19%) samples bacterial growth was detected. The most frequently detected gram-negative bacteria were E.coli 1109 (37%), Klebsiella spp. 242 (8%) and Pseudomonas aeruginosa 136 (4.5%). Klebsiella spp. showed a significant increase of resistance to trimethoprim-sulfamethoxazole by 19% (p = 0.02), ciprofloxacin by 15% (p = 0.01) and ceftazidime by 17% (p = 0.004). E.coli and P. aeruginosa isolates presented no significant differences of antimicrobial susceptibility to the analyzed antibiotics.

CONCLUSIONS

Antimicrobial resistance of Klebsiella spp. increased significant to trimethoprim-sulfamethoxazole, ciprofloxacin and ceftazidime from 2009 to 2012.