Acute pyelonephritis represents a risk factor impairing long-term kidney graft function

Diagnosing and Managing Urinary Tract Infections in Kidney Transplant Recipients

In the article, the authors review antibiotic treatment options for both acute uncomplicated UTI and complicated UTI. In addition, they review alternative regimens which are needed in the setting of drug-resistant pathogens including vancomycin-resistant Enterococcus, -extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E), carbapenem-resistant Enterobacterales, and carbapenem-resistant Pseudomonas, which are encountered with more frequency.

Contrast-enhanced US in Renal Transplant Complications: Overview and Imaging Features

Renal transplant is the first-line treatment of end-stage renal disease. The increasing number of transplants performed every year has led to a larger population of transplant patients. Complications may arise during the perioperative and postoperative periods, and imaging plays a key role in this scenario. Contrast-enhanced US (CEUS) is a safe tool that adds additional value to US. Contrast agents are usually administered intravenously, but urinary tract anatomy and complications such as stenosis or leak can be studied using intracavitary administration of contrast agents. Assessment of the graft and iliac vessels with CEUS is particularly helpful in identifying vascular and parenchymal complications, such as arterial or venous thrombosis and stenosis, acute tubular injury, or cortical necrosis, which can lead to graft loss. Furthermore, infectious and malignant graft involvement can be accurately studied with CEUS, which can help in detection of renal abscesses and in the differentiation between benign and malignant disease. CEUS is also useful in interventional procedures, helping to guide percutaneous aspiration of collections with better delimitation of the graft boundaries and to guide renal graft biopsies by avoiding avascular areas. Potential postprocedural vascular complications, such as pseudoaneurysm, arteriovenous fistula, or active bleeding, are identified with CEUS. In addition, newer quantification tools such as CEUS perfusion are promising, but further studies are needed to approve its use for clinical purposes. ©RSNA, 2024 Supplemental material is available for this article.

Different profiles of acute graft pyelonephritis among kidney recipients from standard or elderly donors

Background

Acute graft pyelonephritis (AGPN) is a relatively common complication in kidney transplants (KTs); however, the effects on allograft function, diagnostic criteria, and risk factors are not well established.

Methods

Retrospective analysis of all consecutive adult KTs was performed between 01 January 2011 and 31 December 2018 (follow-up ended on 31 December 2019) to examine the association between the diagnosis of AGPN (confirmed with magnetic resonance imaging [MRI]) during the first post-transplantation year and graft outcomes.

Results

Among the 939 consecutive KTs (≈50% with donors ≥60 years), we identified 130 MRI-confirmed AGPN episodes, with a documented association with recurrent and multidrug-resistant bacterial urinary tract infections (UTIs) (p < 0.005). Ureteral stenosis was the only risk factor associated with AGPN (OR 2.9 [95% CI, 1.6 to 5.2]). KTs with AGPN had a decreased allograft function at the first year (ΔeGFR 6 mL/min/1.73 m2 [-2-15] in non-AGPN vs. -0.2 [-6.5-8.5] in AGPN, p < 0.001), with similar and negative profiles in KTs from standard or elderly donors. However, only KTs with AGPN and a donor <60 years showed reduced death-censored graft survival (p = 0.015); most of this subgroup received anti-thymocyte globulin (ATG) induction (40.4% vs. 17.7%), and their MRI presented either a multifocal AGPN pattern (73.9% vs. 56.7%) or abscedation (28.3% vs. 11.7%). No difference was noted in death-censored graft survival between early (<3 months post-KT) or late (3-12 months) AGPN, solitary/recurrent forms, or types of multidrug-resistant pathogens. Linear regression confirmed the independent role of multifocal pattern, abscedation, ATG induction, and donor age on the eGFR at the first year.

Conclusion

AGPN, influenced by multifocal presentation, ATG induction, donor age, and abscedation, affects kidney function and significantly impacts allograft survival in KTs with donors <60 years.

Toward an optimization of empirical antibiotic therapy in acute graft pyelonephritis: A retrospective multicenter study

OBJECTIVE

Acute graft pyelonephritis (AGPN) is the most frequent infectious complication in kidney transplant recipients (KTR). The treatment of acute community-acquired (CA) pyelonephritis is based on third-generation cephalosporins (3GC) and fluoroquinolones. Cefepime or a piperacillin-tazobactam combination are more often used in healthcare-associated (HCA) infections. However, these recommendations do not consider the resistance observed in KTRs. The objective of our study was to define the most appropriate empirical antibiotherapy for AGPN in KTRs according to the CA and HCA settings. To answer this question, we assessed the prevalence of resistance to different antibiotics usually recommended for urinary tract infections (UTIs) in the general population.

METHODS

Observational, retrospective, multicenter study covering all episodes of AGPN occurring in hospitalized KTRs in 2019.

RESULTS

A total of 210 patients were included in 7 centers and 244 episodes of AGPN were analyzed (158 CA-AGPN and 86 HCA-AGPN). The prevalence of 3GC and fluoroquinolone resistance was 23 % (n = 36) and 30 % (n = 50) in CA infections (n = 158), and 47 % (n = 40) and 31 % (n = 27) in HCA infections (n = 86), respectively. Cefepime resistance rate was 19 % (n = 30) in CA-AGPN and 29 % (n = 25) in HCA-AGPN. Piperacillin-tazobactam combination had resistance rates > 15 % in both CA and HCA infections. The only antimicrobials with resistance rates < 10 % were aminoglycosides and carbapenems.

CONCLUSION

None of the antibiotics recommended in empirical treatment in UTIs has shown a resistance rate of less than 10% with regard to AGPN. Therefore, none of them should be used as monotherapy. A combination therapy including amikacin could be an appropriate strategy in this setting.

Frequency and impact on renal transplant outcomes of urinary tract infections due to extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species

Background

Enterobacterales are often responsible for urinary tract infection (UTI) in kidney transplant recipients. Among these, Escherichia coli or Klebsiella species producing extended-spectrum beta-lactamase (ESBL) are emerging. However, there are only scarce data on frequency and impact of ESBL-UTI on transplant outcomes.

Methods

We investigated frequency and impact of first-year UTI events with ESBL Escherichia coli and/or Klebsiella species in a prospective multicenter cohort consisting of 1,482 kidney transplants performed between 2012 and 2017, focusing only on 389 kidney transplants having at least one UTI with Escherichia coli and/or Klebsiella species. The cohort had a median follow-up of four years.

Results

In total, 139/825 (17%) first-year UTI events in 69/389 (18%) transplant recipients were caused by ESBL-producing strains. Both UTI phenotypes and proportion among all UTI events over time were not different compared with UTI caused by non-ESBL-producing strains. However, hospitalizations in UTI with ESBL-producing strains were more often observed (39% versus 26%, p = 0.04). Transplant recipients with first-year UTI events with an ESBL-producing strain had more frequently recurrent UTI (33% versus 18%, p = 0.02) but there was no significant difference in one-year kidney function as well as longer-term graft and patient survival between patients with and without ESBL-UTI.

Conclusion

First-year UTI events with ESBL-producing Escherichia coli and/or Klebsiella species are associated with a higher need for hospitalization but do neither impact allograft function nor allograft and patient survival.

Outcomes of asymptomatic histologic pyelonephritis of kidney transplant

BACKGROUND

Urinary Tract Infections are the most common post-transplant infection and can have varied presentations. This study aimed to describe the outcomes of kidney transplant recipients with asymptomatic histologic pyelonephritis on allograft biopsy. Histologic Pyelonephritis was defined as neutrophil cast or neutrophilic tubulitis, interstitial infiltrates with predominant neutrophils, and no evidence of rejection or glomerulonephritis on biopsy.

METHODS

The study included 123 kidney transplant recipients, of whom 95 underwent protocol biopsies, and 28 had biopsies for elevated creatinine within the first 2 years of a kidney transplant.

RESULTS

The mean age of the cohort was 55.3 years, with 52% females and 78% deceased donor transplants. The risk factors for asymptomatic histologic pyelonephritis were recipient female sex (OR 1.89, 1.3-2.7, diabetes mellitus (OR 2.479, 1.687-3.645), and deceased donation (OR 1.69, 1.098-2.63). The incidence of asymptomatic pyelonephritis on protocol biopsy was 1.7%, with 52% having positive urine cultures and Escherichia coli being the most common bacteria. Subjects with asymptomatic pyelonephritis had inferior graft survival compared to the matched cohort HR 1.88 (1.06-3.35), p = .0281. In addition, of these 123 subjects, 68 (55%) subsequently developed pyelonephritis, and 34 subjects had pyelonephritis within 6 months after this episode. Subjects with recurrent infections exhibited lower survival HR 2.86 (1.36-6.02) and a trend toward higher rejection risk.

CONCLUSION

Asymptomatic histologic pyelonephritis can occur in kidney transplant recipients and is associated with inferior graft survival.

Aptitude of Uropathogenic Escherichia coli in Renal Transplant Recipients: A Comprehensive Review on Characteristic Features, and Production of Extended Spectrum β-Lactamase

Urinary tract infection is the most common infection in almost half of the renal transplant patients. The development of UTI in these patients may progress to bacteremia, acute T cell-mediated rejection, impaired allograft function, or allograft loss, along with the increased risk of hospitalization and death. Among various pathogens implicated, Uropathogenic E. coli (UPEC), especially sequence type 131 (ST131), is the most virulent and multidrug-resistant pathogen. High antimicrobial resistance to most β-lactam antibiotics, mediated by extended spectrum β-lactamases (ESBLs) produced by UPEC, is a challenge in the clinical management of UTIs in kidney transplant recipients. Indeed, multidrug resistance to β-lactam antibiotics is a direct consequence of ESBL production. Resistance to other antibiotics such as aminoglycosides, fluoroquinolones, and trimethoprim-sulphamethoxazole has also been reported in ESBLs-producing UPEC, which reduces the therapeutic options, rising healthcare-associated costs and subsequently leads to renal failure or even graft loss. In this review, we aimed to discuss the post-transplant risk factors of UTI, UPEC virulence factors (VF), and the related factors including quorum sensing, and stress resistance genes. Furthermore, we searched for the current treatment strategies and some of the alternate approaches proposed as therapeutic options that may affirm the treatment of ESBL-producing UPEC.

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.

Vesico-ureteric reflux in children and young people undergoing kidney transplantation

Vesico-ureteric reflux (VUR) into transplanted kidneys in children and young people is a common occurrence, found in 19 to 60% of those who had an anti-reflux procedure and up to 79% in the absence of such a procedure. While VUR is unlikely to be of concern without evidence of symptomatic urinary tract infections, less certainty exists regarding outcomes when the VUR is associated with urinary tract infection (UTI) and transplant pyelonephritis. Issues explored will include additional risk factors that might predispose to UTI, any effect of pyelonephritis on acute and long-term kidney allograft function and practical strategies that may reduce the prevalence of infection.

Early versus late removal of urinary catheter after kidney transplantation

BACKGROUND

The optimal treatment for end-stage kidney disease is kidney transplantation. During the operation, a catheter is introduced into the bladder and remains in place postoperatively to allow the bladder to drain. This decreases tension from the cysto-ureteric anastomosis and promotes healing. Unfortunately, urinary catheters can pose an infection risk to patients as they allow bacteria into the bladder, potentially resulting in a urinary tract infection (UTI). The longer the catheter remains in place, the greater the risk of developing a UTI. There is no consensus approach to the time a catheter should remain in place post-transplant. Furthermore, the different timings of catheter removal are thought to be associated with different incidences of UTI and postoperative complications, such as anastomotic breakdown.

OBJECTIVES

This review aimed to compare patients who had their catheter removed < 5 days post-transplant surgery to those patients who had their catheter removed ≥ 5 days following their kidney transplant. Primary outcome measures between the two groups included: the incidence of symptomatic UTIs, the incidence of asymptomatic bacteriuria and the incidence of major urological complications requiring intervention and treatment.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 April 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs comparing timing of catheter removal post-transplantation were eligible for inclusion. All donor types were included, and all recipients were included regardless of age, demographics or type of urinary catheter used.

DATA COLLECTION AND ANALYSIS

Results from the literature search were screened by two authors to identify if they met our inclusion criteria. We designated removal of a urinary catheter before five days (120 hours) as an 'early removal' and anything later than this as a 'late removal.' The studies were assessed for quality using the risk of bias tool. The primary outcome of interest was the incidence of asymptomatic bacteriuria. Statistical analyses were performed using the random effects model, and results were expressed as relative risk (RR) with 95% confidence intervals (CI). Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Two studies (197 patients) were included in our analysis. One study comprised a full-text article, and the other was a conference abstract with very limited information. The risk of bias in the included studies was generally either high or unclear. It is uncertain whether early versus late removal of the urinary catheter made any difference to the incidence of asymptomatic bacteriuria (RR 0.89, 95% Cl 0.17 to 4.57; participants = 197; I2 = 88%; very low certainty evidence). Data on other outcomes, such as the incidence of UTI and the incidence of major urological complications, were lacking. Furthermore, the follow-up of patients across the studies was short, with no patients being followed beyond one month.

AUTHORS' CONCLUSIONS

A high-quality, well-designed RCT is required to compare the effectiveness of early catheter removal versus late catheter removal in patients following a kidney transplant. At the present time, there is insufficient evidence to suggest any difference between early and late catheter removal post-transplant, and the studies investigating this were generally of poor quality.

Pathological Approach to Kidney Allograft Infection

Infectious agents can pose a significant challenge in kidney transplantation, as they have the potential to cause direct infections in the transplanted kidney. These infections can lead to a decline in kidney function and reduce the longevity of the transplanted kidney. Common post-transplant allograft infections include bacterial pyelonephritis and the BK virus infection, while adenovirus, JC virus, and cytomegalovirus are less frequent but can also lead to significant allograft dysfunctions. The histopathological features of these infections are characterized by the infiltration of inflammatory cells in the kidney interstitial area and the presence of viral nuclear inclusions or cytopathic changes in the renal tubular epithelial cells. The confirmation of causative organisms can be achieved by immunohistochemical staining or the visualization of viral particles using electron microscopic examination. However, these methods typically require a longer turnaround time and are not readily available in developing countries, unlike standard hematoxylin-eosin staining. Notably, the differential diagnosis of interstitial inflammation in kidney allografts almost always includes T cell-mediated rejection, which has a different treatment approach than allograft infections. The aim of this review was to prompt clinicians to identify diverse pathological alterations as observed in kidney allograft biopsies, thereby facilitating further investigations and the management of suspected kidney allograft infections.

Urinary Tract Infection 1 Year After Kidney Transplant: Effect on Kidney Transplant Outcomes

OBJECTIVES

Transplant is the gold standard treatment for end-stage renal disease, and yet infectious complications frequently arise in kidney recipients in the context of immunosuppression therapy, with urinary tract infection being the most common. We aimed to assess the prevalence of posttransplant urinary tract infections in kidney transplant recipients and assess the effects on kidney allograft and overall patient outcomes.

MATERIAL AND METHODS

We performed a retrospective analysis of data from State University of New York Upstate University Hospital from January 2016 to November 2022 to assess transplant outcomes in patients who underwent a kidney transplant at our center and met the inclusion criteria.

RESULTS

There were 507 renal allograft recipients who met our inclusion criteria and were assessed for the incidence of urinary tract infection within the first year after transplant. Urinary tract infection was recurrent in 113 transplant recipients (55.6%) within the first year, and 118 (58.1%) were on prophylactic antibiotics at urinary tract infection diagnosis. We observed no relation between recurrence of urinary tract infection and use of prophylactic antibiotics (P = .21). Overall allograft survival rate was 92.1% in the urinary tract infection group and 96.7% in the group without urinary tract infection, which was significantly different (P = .02). Urinary tract infection significantly affected allograft survival (hazard ratio, 3.51; 95% CI, 1.49-8.23; P = .004). Overall patient survival rates were 86.7% and 91.4% in the groups with and without urinary tract infection, respectively (P = .08).

CONCLUSIONS

We determined that allograft survival was significantly greater in the group without urinary tract infection versus the urinary tract infection group. We found no relation between urinary tract infection recurrence and prophylactic antibiotics. We also found that overall patient survival was not significantly different in the group with urinary tract infection versus the group without urinary tract infection.

Regulation of gut microbiota: a novel pretreatment for complications in patients who have undergone kidney transplantation

Kidney transplantation is an effective method to improve the condition of patients with end-stage renal disease. The gut microbiota significantly affects the immune system and can be used as an influencing factor to change the prognoses of patients who have undergone kidney transplantation. Recipients after kidney transplantation showed a lower abundance of Firmicutes and Faecalibacterium prausnitzii and a higher proportion of Bacteroidetes and Proteobacteria. After using prebiotics, synbiotics, and fecal microbiota transplantation to regulate the microbial community, the prognoses of patients who underwent kidney transplantation evidently improved. We aimed to determine the relationship between gut microbiota and various postoperative complications inpatients who have undergone kidney transplantation in recent years and to explore how gut microecology affects post-transplant complications. An in-depth understanding of the specific functions of gut microbiota and identification of the actual pathogenic flora during complications in patients undergoing kidney transplantation can help physicians develop strategies to restore the normal intestinal microbiome of transplant patients to maximize their survival and improve their quality of life.

Acute Kidney Injury in Kidney Transplant Patients in Intensive Care Unit: From Pathogenesis to Clinical Management

Kidney transplantation is the first-choice treatment for end-stage renal disease (ESRD). Kidney transplant recipients (KTRs) are at higher risk of experiencing a life-threatening event requiring intensive care unit (ICU) admission, mainly in the late post-transplant period (more than 6 months after transplantation). Urosepsis and bloodstream infections account for almost half of ICU admissions in this population; in addition, potential side effects related to immunosuppressive treatment should be accounted for cytotoxic and ischemic changes induced by calcineurin inhibitor (CNI), sirolimus/CNI-induced thrombotic microangiopathy and posterior reversible encephalopathy syndrome. Throughout the ICU stay, Acute Kidney Injury (AKI) incidence is common and ranges from 10% to 80%, and up to 40% will require renal replacement therapy. In-hospital mortality can reach 30% and correlates with acute illness severity and admission diagnosis. Graft survival is subordinated to baseline estimated glomerular filtration rate (eGFR), clinical presentation, disease severity and potential drug nephrotoxicity. The present review aims to define the impact of AKI events on short- and long-term outcomes in KTRs, focusing on the epidemiologic data regarding AKI incidence in this subpopulation; the pathophysiological mechanisms underlying AKI development and potential AKI biomarkers in kidney transplantation, graft and patients' outcomes; the current diagnostic work up and management of AKI; and the modulation of immunosuppression in ICU-admitted KTRs.

External ureteric stent versus internal double J stent in kidney transplantation: a retrospective analysis on the incidence of urological complications and urinary tract infections

Introduction

Urologic complications (UCs) and urinary tract infections (UTIs) are common after kidney transplantation. Intraoperative stent placement at the vesicoureteric anastomosis reduces UC risk, but increases UTI risk.

Methods

In 2014 our stenting protocol changed from external ureteric stent (ES) to internal double J stent (DJ). We retrospectively studied the occurrence of UCs and UTIs in relation to ES or DJ in 697 kidney recipients.

Methods

An ES was used in 403 patients (57.8%), in 294 (42.2%) a DJ. ES was removed 7-12 days and DJ 3-4 weeks post-operative. Induction immunosuppression was the same in both groups. Primary outcomes at 6 months follow-up were UC (urinary leakage/ureter stenosis) and UTI; they were related to stenting procedure and clinical and transplant characteristics. The incidence of UCs was similar for ES (8.4%) and DJ (6.8%), p=0.389. ES use was a significant risk factor for UTI (OR 1.69 (1.15-2.50), p=0.008). Post-transplant hospitalization was significantly shorter in the DJ group. Despite more acute rejection episodes with ES (ES/DJ: 16.4%/6.1%, p<0.001), no clinical relevant differences in graft outcomes existed.

Discussion

A DJ is, compared to ES, associated with a lower incidence of UTIs and comparable occurrence of UCs and is therefore the preferred technique for stenting the vesicoureteric anastomosis.

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.

Unmet Needs in Complicated Urinary Tract Infections: Challenges, Recommendations, and Emerging Treatment Pathways

While urinary tract infections (UTIs) are one of the most common types of infections globally, the wide variety of presentations and of severity of disease can make it difficult to manage. The definition for uncomplicated UTIs (uUTIs) is generally regarded as UTIs in healthy, non-pregnant women whereas all other UTIs are considered complicated. There is, however, a lack of consensus definition of complicated UTIs (cUTIs), leading to global differences in management. In addition, the patients who develop complicated UTIs generally have other comorbidities that warrant more urgent intervention. One of the biggest challenges in treating cUTIs is the rise of antimicrobial resistance (AMR). While there have been recent drug approvals for new antibiotic to treat these resistant organisms, a multidisciplinary approach, including regulatory frameworks, provider education and public awareness campaigns, is crucial to limiting unnecessary treatments for asymptomatic bacteriuria (ASB) and uUTIs that can ultimately lead to more severe infections.

Treatment of asymptomatic bacteriuria in the first 2 months after kidney transplant: A controlled clinical trial

BACKGROUND

The incidence of urinary tract infections (UTIs) in the first 2 months postrenal transplantation (pRT) is very high. We evaluate the efficacy of asymptomatic bacteriuria (AB) screening and treatment on the incidence of UTI in the first 2 months pRT METHODS: We conducted a randomized controlled clinical trial. A urine culture was obtained in all patients on the day of the bladder catheter removal, on week three, and before removal of the ureteral catheter. The intervention group received treatment for AB. The control group did not receive treatment. The primary outcomes were the cumulative incidence of UTI and/or graft pyelonephritis and the time to the first episode of UTI and/or graft pyelonephritis RESULTS: Eighty patients were randomized, 40 in each group, and the median follow-up was 63 days (IQR 54-70). The average age was 29.8 years and 33.7% (n = 27) were women. The incidences of UTI (n = 10, 25 % vs. n = 4, 10%, p = .07) and pyelonephritis (n = 6, 15% vs. n = 1, 2.5%, p = .04) were greater in the intervention group, as also shown in the survival analysis: UTI (HR2.8, 95% CI 0.8-9.1, p = .07) and pyelonephritis (HR 6.5, 95% CI 0.8-54.7, p = .08), respectively. The most commonly isolated bacterium was Escherichia coli (n = 28, 59.5%), and over half were E. coli with extended-spectrum beta-lactamases (n = 15). A major limitation was not obtaining the calculated sample size due to a delay in patient recruitment resulting from the COVID-19 pandemic CONCLUSION: Treatment of AB in the first 2 months pRT does not decrease the incidence of UTI or graft pyelonephritis and may actually increase their frequency. Routine treatment of AB during the first months after renal transplantation should not be a standard procedure.

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.

Influence of Graft Ureter Length, a Donor-Related Factor, on Urinary Tract Infections After Living-Donor Kidney Transplantation: A Single-Center Analysis of 211 Cases

Urinary tract infection (UTI) occurs in 25% of recipients of living-donor kidney transplantation (LDKT). Female sex, age, and anatomical abnormalities have been reported as recipient-related risk factors for UTI after LDKT; few studies have reported donor-related factors. We retrospectively examined UTI occurrence within 5 years of transplantation in recipients (n = 211) who underwent LDKT at our hospital between April 2011 and April 2021. All nephrectomies were performed using a retroperitoneal pure laparoscopic approach. The ureter was dissected at the lower level of the common iliac artery and trimmed to the shortest length, enough to reach the bladder using extra vesicular ureterocystoneostomy with a 3 cm submucosal tunnel. Twenty-nine recipients (13.7%) developed UTI within 5 years, and the median time to onset was 40.0 days. After adjusting for the well-known factors, including recipient sex, graft ureter length was an independent factor for UTI occurrence (HR 1.25, 95% CI 1.02∼1.53, p = 0.028) in the multivariate Cox regression analysis. The long ureter is usually trimmed, and the widest part is used for anastomosis, which may increase the possibility of reflux from the bladder to the ureter in the standard technique. The ureter length may be associated with the incidence of UTI after LDKT.

Recurrent Urinary Tract Infections in Renal Transplant Recipients: Risk Factors and Outcomes in Low-resource Settings

Recurrent urinary tract infections (UTIs) after kidney transplantation are a common problem adversely affecting graft outcomes. This retrospective study aimed to report the frequency and risk factors of recurrent UTI and their impact on graft and patient outcomes in kidney transplant recipients at the Sindh Institute of Urology and Transplantation, Karachi, Pakistan, in January-December 2015. Five-year graft and patient survival rates were compared among different groups using Kaplan-Meier analysis. Of the 251 recipients, 67 developed one episode of UTI. Of these 67, 29 had 76 episodes of recurrent UTI. Out of the 76 episodes of recurrent UTI, Escherichia coli was the most common pathogen in 32 cases. Organisms causing recurrent UTI showed resistance to carbapenem in 19 cases versus 2 in the non-recurrent UTI group (P = 0.006). The estimated glomerular filtration rate at 1 year was 57.8 ± 16.23 mL/min/1.73 m2 in the recurrent UTI group vs. 61.9 ± 15.7 mL/min/1.73 m2 in the non-recurrent UTI group (P = 0.001). Graft survival in the recurrent UTI group at 5 years was significantly lower (76%) than in the non-recurrent UTI (95%) and no UTI groups (93%) (log-rank P = 0.006), with no significant effect on patient survival in these groups (P = 0.429). The presence of double-J stent (P = 0.036) and cytomegalovirus infections (P = 0.013) independently predicted recurrent UTI. Recurrent UTIs are common in low-resource settings and adversely affect graft outcomes. Appropriate prophylaxis and treatment are important to reduce recurrent UTI to improve graft outcomes.

Revision ureteroneocystostomy in pediatric renal transplant patients for symptomatic vesicoureteral reflux and its effect on recurrent hospitalizations

BACKGROUND

Nearly 13,000 pediatric renal transplantations have been performed since 1987 with improving overall mortality and morbidity; however, graft infection remains a significant post-transplant concern. Recurrent urinary tract infections in pediatric patients with vesicoureteral reflux into their renal transplant can result in graft dysfunction, increased hospital cost, and impaired social and cognitive development due to time spent hospitalized.

OBJECTIVE

To evaluate the effect of revision ureteroneocystostomy on pediatric renal transplant patients with symptomatic vesicoureteral reflux in reducing hospitalizations and recurrent urinary tract infections.

METHODS

We retrospectively reviewed pediatric patients from 2002 through 2021 who underwent renal transplantation and required revision ureteroneocystostomy due to symptomatic vesicoureteral reflux. We analyzed the differences in days hospitalized, days hospitalized due to urinary tract infection, and treated urinary tract infections prior to and after revision ureteroneocystostomy.

RESULTS

Ten patients requiring revision ureteroneocystostomy secondary to symptomatic vesicoureteral reflux were identified. There was no difference in the observation time between transplant to revision, and revision to last follow up (2.3 years (IQR 1.3-6.5) vs 1.7 years (IQR 1-6.7), p = 0.4446). Overall, there was a significant decrease in the total number of hospitalization days (21.5 days (IQR 3-43) vs 5.5 days (IQR 0-9), p = 0.006), total number of hospitalization days related to urinary tract infection (14.5 days (IQR 3-28) vs 0 days (IQR 0-3), p = 0.008) and treated urinary tract infections (3.5 (IQR 3-6) vs 1 (IQR 0-2), p = 0.019) following revision ureteroneocystostomy. The rate of hospitalization days for urinary tract infection was also significantly decreased following revision ureteroneocystostomy (7.15 per/year (IQR 0.4-11.75) vs 0 per/year (IQR 0-0.8), p = 0.008).

DISCUSSION

Symptomatic vesicoureteral reflux in pediatric transplant patients is difficult to manage and some patients will ultimately require surgery. There have been previous studies on the success of revision ureteroneocystostomy in treating reflux but no data on the reduction in hospitalizations associated with recurrent infections following the procedure. Limitations of this study are the small cohort size, retrospective nature, multi-surgeon study, and inherent selection bias due to evaluation of only surgical patients.

CONCLUSION

Revision ureteroneocystostomy can limit the negative consequences of recurrent graft infections with reduction in hospitalization days and improved hospitalization rates due to urinary tract infections. The reduction in hospitalizations can greatly improve the cost of care along with quality of life for transplant patients and should be strongly considered in children with symptomatic vesicoureteral reflux who have failed conservative therapy.

Shorter durations of antibiotic therapy in organ transplant

PURPOSE OF REVIEW

Recent evidence supports shorter courses of antibiotics for several common infections and prophylactic indications. Unfortunately, solid organ transplant patients are often underrepresented or excluded from these studies. As a result, prolonged antibiotic durations are often used in clinical practice despite a lack of demonstrable benefit. This paper reviews recent publications addressing antibiotic duration of therapy in SOT recipients.

RECENT FINDINGS

Although largely limited to observational studies, longer courses of antibiotics for surgical prophylaxis, urinary tract infections, and bloodstream infections have not demonstrated benefit compared to shorter courses. In some instances, longer courses of therapy have been associated with harm (i.e., adverse drug events and development of resistance).

SUMMARY

Although the data remains limited, findings from retrospective studies evaluating shorter courses of antibiotics in SOT patients is encouraging. More robust research is desperately needed to define the optimal duration of antibiotics for common infections in SOT patients.

Impact of different urinary tract infection phenotypes within the first year post-transplant on renal allograft outcomes

In this study, we investigated the clinical impact of different urinary tract infection (UTI) phenotypes occurring within the first year after renal transplantation. The population included 2368 transplantations having 2363 UTI events. Patients were categorized into four groups based on their compiled UTI events observed within the first year after transplantation: (i) no colonization or UTI (n = 1404; 59%), (ii) colonization only (n = 353; 15%), (iii) occasional UTI with 1-2 episodes (n = 456; 19%), and (iv) recurrent UTI with ≥3 episodes (n = 155; 7%). One-year mortality and graft loss rate were not different among the four groups, but patients with recurrent UTI had a 7-10 ml/min lower eGFR at year one (44 ml/min vs. 54, 53, and 51 ml/min; p < .001). UTI phenotypes had no impact on long-term patient survival (p = .33). However, patients with recurrent UTI demonstrated a 10% lower long-term death-censored allograft survival (p < .001). Furthermore, recurrent UTI was a strong and independent risk factor for reduced death-censored allograft survival in a multivariable analysis (HR 4.41, 95% CI 2.53-7.68, p < .001). We conclude that colonization and occasional UTI have no impact on pertinent outcomes, but recurrent UTI are associated with lower one-year eGFR and lower long-term death-censored allograft survival. Better strategies to prevent and treat recurrent UTI are needed.

Early versus late acute graft pyelonephritis: A retrospective analysis of graft and patient outcomes

BACKGROUND

Acute graft pyelonephritis (AGPN) is thought to affect graft and patient survival among renal transplant recipients. The objective was to compare outcomes among early AGPN (<6 months from transplant) versus late AGPN (>6 months from transplant).

METHODS

This retrospective study analysed 150 patients with AGPN dividing them into early and late AGPN from 2008 to 2016. Predictors of graft loss and mortality were compared using logistic regression analysis. Graft survival and patient survival were analysed using Kaplan-Meyer survival plots.

RESULTS

55.3% (n = 83) had early AGPN and 44.7% (n = 67) had late AGPN. In an early AGPN group, 13.3% had CMV disease on the follow-up, compared to only 3% in the late AGPN group (p > 0.05). Furthermore, 38.6% had prolonged DJ stent in-situ (> 2 weeks) following transplant surgery in the early AGPN compared to only 19.4% in the late AGPN group (p < 0.05). Recurrent GPN was more common in the late AGPN group - (35.8% versus 18.1%). The presence of renal abscess was predictive of graft loss in Univariate analysis (HR-6.12, p < 0.004). There was decreased death-censored graft survival in the early AGPN group (p = 0.035), without a significant difference in the patient survival among the two groups.

CONCLUSION

The occurrence of early AGPN had a significant impact on long-term graft survival in renal transplant recipients, with no significant effect on patient survival. This study underlines the paramount importance of the prevention of urinary tract infection (UTI) in renal transplant recipients.

Effects of Bacterial Urinary Tract Infection on Clinical Outcome and Survival of Kidney Transplant Patients

BACKGROUND

There is no consensus on whether the development of urinary tract infections (UTIs) leads to high mortality or graft loss in kidney transplant patients. A high incidence of multidrug resistant (MDR) infections was observed worldwide and is associated with these complications. The aim of this study was to analyze the effects of UTIs on the clinical outcome and survival in kidney transplant patients.

METHODS

This retrospective study evaluated 601 kidney transplant patients who were categorized as follows: group 1 (G1) patients without a UTI, group 2 (G2) patients with a UTI, and group 3 (G3) recipients with a recurrent UTI. Patients were followed up for at least 1 year after transplantation. Graft survival, risk of graft loss, and risk of developing a UTI were analyzed by the Kaplan-Meier method, Cox regression, and logistic regression methods, respectively. Differences with P < .05 were considered statistically significant.

RESULTS

The proportion of rejection episodes was higher in G3 (32.35%) than in G1 (20.89%) and G2 (21.88%) (P < .001). The graft survival after the 10-year follow-up was better in G1 (73.29%) than in G3 (61.62%) (P = .019). UTI recurrent episodes increased the risk of graft loss >2.5-fold. Women and those who received a kidney from a deceased donor (DD) were at risk of at least 1 UTI event during follow-up. A greater proportion of MDR infections was observed in G3 than in G2 (P < .001).

CONCLUSIONS

The risk factors for developing a UTI were female sex, receiving a DD kidney, susceptibility to other infections, episodes of rejection, and delayed graft function. Moreover, a UTI, especially a recurrent UTI, was an important risk factor for allograft loss.

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.

Risk Factors and Outcomes of Acute Graft Pyelonephritis with Bacteremia Due to Multidrug-Resistant Gram-Negative Bacilli among Kidney Transplant Recipients

Acute graft pyelonephritis (AGP) is the leading cause of bloodstream infection in kidney transplant (KT) recipients. The prevalence of urinary tract infections caused by multidrug-resistant (MDR) Gram-negative bacilli is increasing. This 14-year prospective observational study sought to determine the clinical characteristics, risk factors, and outcomes of AGP with bacteremia due to MDR Gram-negative bacilli. Overall, 278 episodes of AGP with bacteremia due to MDR Gram-negative and non-MDR Gram-negative bacilli were identified and compared in 214 KT recipients; MDR Gram-negative bacilli were the cause in 28.4%. Overall 30-day mortality was low (1.1%). Risk factors independently associated with AGP due to MDR Gram-negative bacilli were male sex (OR 3.08; 95%CI 1.60–5.93), previous episode of bacteremic AGP (OR 2.11, 95%CI 1.09–4.09), prior antibiotic therapy in the preceding month (OR 2.47, 95%CI 1.33–4.57), and nosocomial acquisition (OR 2.03, 95%CI 1.14–3.62). Forty-three percent of MDR Gram-negative episodes received inappropriate empirical antibiotic therapy. The risk factors identified in this study may help physicians when selecting empirical antibiotic treatment for AGP. Previous antibiotic use was the main modifiable factor. Its presence highlights the importance of avoiding unnecessary antibiotics in order to bring down the high rates of MDR Gram-negative bacilli infections in this population.

Urinary Tract Infection among Post-renal Transplant Patients in the Department of Nephrology of a Tertiary Care Centre: A Descriptive Cross-sectional Study

Introduction

Urinary tract infection is the most common infection among renal transplant recipients and increases the risk of hospitalization or even death. The study aimed to find the prevalence of urinary tract infection among post-renal transplant patients in the Department of Nephrology of a tertiary care centre.

Methods

This is a descriptive cross-sectional study which was conducted among 217 post-renal transplant patients at the Department of Nephrology of a tertiary care centre from 1st November, 2017 to 31st October, 2018. The study was approved by the Institutional Review Committee (Reference number: 245(6-11-E)2074-75). Convenience sampling was used. The data were entered in Microsoft Excel 2011 and analyzed using the Statistical Package for the Social Sciences version 20.0. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data and mean with standard deviation for continuous data.

Results

Among 217 patients, urinary tract infection was seen in 27 (12.44%) (8.05-16.83 at 95% Confidence Interval). One (3.70%) patient had the infection within three months of transplant, and 17 (62.96%) had infection after more than a year of transplant.

Conclusions

The prevalence of urinary tract infection among kidney transplant recipients in our study was lower than previous studies done in similar settings.

Keywords

Escherichia coli; hypertension; kidney; transplants.

Impact of Late and Recurrent Acute Graft Pyelonephritis on Long-Term Kidney Graft Outcomes

Background

While Urinary tract infections are the most common infections in kidney transplant recipients, the impact of late acute graft pyelonephritis (AGPN) on graft outcomes remains unknown. Our study was performed to more precisely evaluate the long-term impact of AGPN.

Methods

We included 9052 kidney and combined kidney-pancreas recipients who underwent transplantation between 2008 and 2018 from a French multicenter cohort. The relationships between AGPN and patient and graft survival were analyzed with a time-dependent multivariate Cox model.

Results

The cumulative incidence of AGPN was 20.9%. A first episode of early AGPN is associated with a non-significant increase in the risk of graft failure (hazard ratio [HR], 1.27; 95% confidence interval [95% CI], 0.90 to 1.79). Though, cumulative number of AGPN episodes (HR = 1.51; 95% CI, 0.89 to 2.57 for two episodes and HR = 2.08; 95% CI, 1.17 to 3.69 for three or more episodes) is associated with an increased risk of graft failure. In contrast, when the first episode of AGPN occurred late (i.e., 6 months post transplantation), the risk of graft failure is significantly increased (HR = 2.25; 95% CI, 1.65 to 3.07), and this risk remains relatively stable with the recurrence of late AGPN episodes. The onset of late AGPN were also associated with a higher risk of patient death.

Conclusion

This analysis shows that late AGPN and recurrent AGPN are both risk factors for a poor long-term graft outcome and mortality. Late AGPN should not be considered benign infections in post-transplantation follow-up.

Acute Allograft Pyelonephritis: Vague Symptoms, Indeterminate Laboratory Results, and the Necessity of Indication Biopsy

OBJECTIVES

In this study, we examined the clinical and biochemical features of biopsy-proven acute pyelonephritis among 769 kidney transplant recipients.

MATERIALS AND METHODS

This cohort study was performed between January 2003 and December 2019 at the University of Health Sciences (Izmir, Turkey). Acute pyelonephritis refers to urinary tract infection with acute graft dysfunction. All patients with suspected acute pyelonephritis underwent diagnostic biopsy and received antibiotic treatment for an average of 14 to 21 days. Patients with acute pyelonephritis (18/769, 2.3%) were categorized into groups of 9 patients each: group 1 developed acute pyelonephritis in the first 6 months, and group 2 developed acute pyelonephritis >6 months posttransplant.

RESULTS

All patients in group 1 had acute graft dysfunction; only 2 (22%) were symptomatic. All patients recovered baseline graft function after treatment. Patients in group 2 had at least 2 laboratory findings that included leukocytosis, neutrophilia, and high C-reactive protein values. Six patients had urine culture positivity. Recurrent pyelonephritis occurred in 3 patients. Four patients had graft loss. Over the mean follow-up of 48.0 ± 28.4 months, 14 patients (78%) were alive with a functioning graft.

CONCLUSIONS

Diagnostic biopsy is of great importance in patients with urinary tract infection accompanied by acute graft dysfunction in the first 6 months after transplant.

Immunosuppressive therapy after solid organ transplantation and the gut microbiota: Bidirectional interactions with clinical consequences

Our understanding of the involvement of the gut microbiota (GM) in human health has expanded exponentially over the last few decades, particularly in the fields of metabolism, inflammation, and immunology. Immunosuppressive treatment (IST) prescribed to solid organ transplant (SOT) recipients produces GM changes that affect these different processes. This review aims at describing the current knowledge of how IST changes the GM. Overall, SOT followed by IST results in persistent changes in the GM, with a consistent increase in proteobacteria including opportunistic pathobionts. In mice, Tacrolimus induces dysbiosis and metabolic disorders, and alters the intestinal barrier. The transfer of the GM from Tacrolimus-treated hosts confers immunosuppressive properties, suggesting a contributory role for the GM in this drug's efficacy. Steroids induce dysbiosis and intestinal barrier alterations, and also seem to depend partly on the GM for their immunosuppressive and metabolic effects. Mycophenolate Mofetil, frequently responsible for digestive side effects such as diarrhea and colitis, is associated with pro-inflammatory dysbiosis and increased endotoxemia. Alemtuzumab, m-TOR inhibitors, and belatacept have shown more marginal impact on the GM. Most of these observations are descriptive. Future studies should explore the underlying mechanism of IST-induced dysbiosis in order to better understand their efficacy and safety characteristics.

Bacterial and Viral Infection and Sepsis in Kidney Transplanted Patients

Kidney transplanted patients are a unique population with intrinsic susceptibility to viral and bacterial infections, mainly (but not exclusively) due to continuous immunosuppression. In this setting, infectious episodes remain among the most important causes of death, with different risks according to the degree of immunosuppression, time after transplantation, type of infection, and patient conditions. Prevention, early diagnosis, and appropriate therapy are the goals of infective management, taking into account that some specific characteristics of transplanted patients may cause a delay (the absence of fever or inflammatory symptoms, the negativity of serological tests commonly adopted for the general population, or the atypical anatomical presentation depending on the surgical site and graft implantation). This review considers the recent available findings of the most common viral and bacterial infection in kidney transplanted patients and explores risk factors and outcomes in septic evolution.

Association between acute graft pyelonephritis and kidney graft survival: A single-center observational study

The association between acute graft pyelonephritis (AGPN) and graft failure in kidney transplant recipients (KTR) remains controversial. In this single-center observational study, we aimed to assess the incidence of AGPN as a time-dependent posttransplantation event. We also examined the association between the diagnosis of AGPN and graft outcomes. In total, we evaluated 1480 patients who underwent kidney transplantation between January 2007 and December 2017. During a median follow-up of 5.04 years, we observed 297 AGPN episodes that occurred in 158 KTR. To evaluate the association between AGPN and clinical outcomes, we performed Cox proportional hazards regression analyses in which AGPN was entered as a time-dependent covariate. AGPN was independently associated with an increased risk of graft loss (hazard ratio = 1.66; 95% confidence interval [CI]: 1.05-2.64, p < .03) and a persistently decreased eGFR (fixed effect on intercept: -2.29 ml/min/1.73 m² ; 95% CI: from -3.23 to -1.35, p < .01). However, neither mortality nor biopsy-proven acute rejection was found to correlate with AGPN. Moreover, recurrent AGPN episodes did not appear to have an additive detrimental impact on graft loss. These data represent a promising step in understanding whether AGPN prevention may decrease the risk of graft loss in KTR.

Short versus prolonged antibiotic treatment for complicated urinary tract infection after kidney transplantation

There is no consensus regarding the optimal duration of antibiotic therapy for urinary tract infection (UTI) following kidney transplantation (KT). We performed a retrospective study comparing short (6-10 days) versus prolonged (11-21 days) antibiotic therapy for complicated UTI among KT recipients. Univariate and inverse probability treatment weighted (IPTW) adjusted multivariate analysis for composite primary outcome of all-cause mortality or readmissions within 30 days and relapsed UTI 180 days were performed. Overall, 214 KT recipients with complicated UTI were included; 115 short-course treatment (median 8, interquartile range [IQR] 6-9 days), 99 prolonged course (median 14, IQR 12-21 days). The composite outcome occurred in 33 (28.6%) in the short-course group and 30 (30%) in the prolonged-course group; relapsed UTI occurred in 19 (16.5%) vs. 21 (21%), respectively. Duration of antibiotic treatment was not associated with any of these outcomes. The only risk factor for mortality/readmissions in multivariate analysis was deceased donor. No differences between groups were demonstrated for length of hospital stay, rates of bacteraemia, resistance development, and serum creatinine at 30 and 90 days. In conclusion, we found no difference in clinical outcomes between KT recipients treated for complicated UTI with short-course antibiotic (6-10 days) versus longer course (11-21 days).

Pyelonephritis and Bacteremia Caused by Klebsiella variicola following Renal Transplantation

Klebsiella variicola (K. variicola) is a Gram-negative organism genetically similar to Klebsiella pneumoniae (K. pneumoniae) that can cause a variety of diseases in humans. Bacteremia due to K. variicola is associated with a higher mortality rate than bacteremia with K. pneumoniae. Here, we describe a 65-year-old woman who developed pyelonephritis 2 months after receiving a renal transplantation following a longstanding history of end-stage renal disease secondary to polycystic kidney disease. Her creatinine on admission was unchanged from her posttransplant baseline, and an abdominal CT scan showed inflammatory changes around the transplanted kidney that were suggestive of an infection rather than allograft rejection. She was initially treated empirically with meropenem given a history of extended-spectrum beta-lactamase- (ESBL-) producing E. coli bacteriuria. After a day of therapy with meropenem, her therapy was streamlined based on culture results to ceftriaxone. She continued to improve, her kidney function remained stable, and she was prescribed oral ciprofloxacin to complete a 14-day total course of antibiotics. This case is the first reported instance of K. variicola bacteremia associated with pyelonephritis in a renal transplant recipient. Hospitalization with acute pyelonephritis within the first year following kidney transplant is common and is associated with increased risk of graft loss and mortality. However, K. variicola is not a commonly known organism to cause this infection. Despite the risk of allograft failure in this circumstance, this patient was successfully treated with a 14-day course of antibiotic therapy.

Significance of Asymptomatic Pyelonephritis Found on Kidney Transplant Biopsy

The clinical significance and appropriate management of graft pyelonephritis diagnosed by biopsy are poorly understood.

Methods

We analyzed data from all patients with pyelonephritis on transplant kidney biopsy from January 1998 to December 2019. Patients were divided into 2 groups: those whose urinalysis was positive for urinary tract infection (UA+) and those whose urinalysis was negative (UA-).

Results

There were a total of 101 patients with the diagnosis of pyelonephritis by biopsy during the study period. The mean time from transplant to pyelonephritis diagnosis was 3.3 ± 4 y. Thirty-six (35.6%) of the patients with pyelonephritis on biopsy had a negative UA. Out of 65 patients in the UA+ group, 54 (83%) received antibiotics. Only 12 of the UA- patients (33%) received antibiotics. The use of antibiotics in both the UA+ (P = 0.03) and UA- groups (P = 0.02) compared with no use of antibiotics was associated with better death-censored graft survival. On multivariate analysis, the use of antibiotics (hazard ratio = 0.22, P = 0.001, 95% confidence interval, 0.12-0.61) was associated with improved graft survival.

Conclusion

The finding of pyelonephritis on a transplant kidney biopsy is almost always a surprise but is an important finding. Treatment with antibiotics, regardless of signs or symptoms of urinary tract infection, is associated with improved graft survival.

What Is the Part of Tropical Diseases Among Infectious Complications in Renal Transplant Recipients in the Amazon? A 12-Year Multicenter Retrospective Analysis in French Guiana

BACKGROUND

Infectious complications in kidney transplant recipients (KTRs) are well studied in temperate countries but remain barely known in tropical ones. The main objective of this study was to describe infection-related hospitalizations in patients living in the Amazon, where it has never been described.

METHODS

All KTRs residing in French Guiana between 2007 and 2018 were included retrospectively. Infection-related hospitalizations were collected in the main medical centers of the territory.

RESULTS

Eighty-two patients were included, and 42 were infected during the study period (51%). Eighty-seven infections were identified. The main sites of infection were urinary, in 29% of cases (25/87), and pulmonary, in 22% of cases (19/87). When documented (48/87), bacterial infections were predominant (35/48), followed by viral (8/48), fungal (4/48), and parasitic infections (1/48). Endemic so-called tropical infections accounted for 6% of infections (5/87). Histoplasma capsulatum was the most commonly isolated fungus (2/4).

CONCLUSIONS

This study suggests that the spectrum of infections in KTRs in French Guiana differs little from that of temperate countries. Nevertheless, some tropical infections are described. More studies on fungal infections in KTRs should be undertaken to clarify the weight of histoplasmosis in these patients.

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.

Asymptomatic Bacteriuria in Post Renal Transplant Patients: To Treat or Not?

Urinary tract infections (UTIs) can commonly occur within the first few weeks following kidney transplantation procedures. Although the management of asymptomatic bacteriuria and acute graft pyelonephritis is important to reduce the risk of graft rejections following kidney transplantation, the efficacy of antibiotics administration remains controversial among studies in the literature. The aim of this review is to elaborate more on asymptomatic bacteriuria following kidney transplantation and try to formulate proper evidence about the efficacy of antibiotics administration on eliminating the frequency of infections and enhancing the quality of care for patients. Most studies in the literature are observational, which are usually biased in the interventions. However, the current evidence regarding the management and screening of asymptomatic bacteriuria seems to discourage such an approach. Almost all of the included studies reported that antibiotic administration did not significantly lower the rates of secondary symptomatic UTIs or enhance the functions of the graft. In addition, there is no significant impact on mortality and other clinical outcomes. Lastly, the frequent administration of antibiotics can significantly increase the risk of recurrence due to the emergence of novel strains of bacteria that are resistant to the currently administered antibiotics making it unfavorable.

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.

Care for the organ transplant recipient on the intensive care unit

All transplant recipients receive tacrolimus, mycophenolate and glucocorticoids and these drugs have many side-effects and drug-drug interactions. Common complications include surgical complications, infections, rejection and acute kidney injury. Infections as CMV and PJP can be prevented with prophylactic treatment. Given the complexity of organ transplant recipients a multi-disciplinary team of intensivists, surgeons, pharmacists and transplant specialists is essential. After heart transplantation a temporary pacemaker is required until the conduction system recovers. Stiffening of the heart and increased cardiac markers indicate rejection. An endomyocardial biopsy is performed via the right jugular vein, necessitating its preservation. For lung transplant patients, early intervention for aspiration is warranted to prevent chronic rejection. Risk of any infection is high, requiring active surveillance and intensive treatment, mainly of fungal infections. The liver is immunotolerant requiring lower immunosuppression. Transplantation surgery is often accompanied by massive blood loss and coagulopathy. Other complications include portal vein or hepatic artery thrombosis and biliary leakage or stenosis. Kidney transplant recipients have a high risk of cardiovascular disease and posttransplant anemia should be treated liberally. After postmortal transplantation, delayed graft function is common and dialysis is continued. Ureteral anastomosis complications can be diagnosed with ultrasound.

Impact of Treating Asymptomatic Bacteriuria in Kidney Transplant Recipients: A Prospective Cohort Study

This study aims to define the epidemiologic, clinical, and microbiological features of asymptomatic bacteriuria (AB) and cystitis in kidney transplantation recipients (KTRs), and to determine the impact of antimicrobial therapy of AB and the risk factors of cystitis. We conducted a prospective observational study of AB and cystitis in KTRs from January to June 2017. One-hundred ninety seven KTRs were included: 175 (88.8%) with AB and 22 (11.2%) with cystitis. The most frequent etiologies were Escherichia coli, Klebsiellapneumoniae, Enterococcusfaecalis, and Pseudomonas aeruginosa. No differences were observed regarding the etiologies, antimicrobial susceptibility patterns, and microbiologic outcomes in AB vs. cystitis. The treatment of AB diminished the microbiological cure and increased the rates of microbiologic relapses and reinfections; in addition, treated AB patients showed a trend of developing symptomatic urinary tract infection in the following six months. The analysis of the data identified the following independent risk factors for cystitis during the six months of follow-up: AB treatment, thymoglobulin induction, previous acute pyelonephritis, and time since transplantation < 1 year. In summary, considering the lack of clinical benefits of treating AB and its impact on cystitis development in the follow-up, we support the recommendation of not screening for or treating AB.

Efficacy of β-lactam/β-lactamase inhibitors to treat extended-spectrum beta-lactamase-producing Enterobacterales bacteremia secondary to urinary tract infection in kidney transplant recipients (INCREMENT-SOT Project)

BACKGROUND

Whether active therapy with β-lactam/β-lactamase inhibitors (BLBLI) is as affective as carbapenems for extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) bloodstream infection (BSI) secondary to urinary tract infection (UTI) in kidney transplant recipients (KTRs) remains unclear.

METHODS

We retrospectively evaluated 306 KTR admitted to 30 centers from January 2014 to October 2016. Therapeutic failure (lack of cure or clinical improvement and/or death from any cause) at days 7 and 30 from ESBL-E BSI onset was the primary and secondary study outcomes, respectively.

RESULTS

Therapeutic failure at days 7 and 30 occurred in 8.2% (25/306) and 13.4% (41/306) of patients. Hospital-acquired BSI (adjusted OR [aOR]: 4.10; 95% confidence interval [CI]: 1.50-11.20) and Pitt score (aOR: 1.47; 95% CI: 1.21-1.77) were independently associated with therapeutic failure at day 7. Age-adjusted Charlson Index (aOR: 1.25; 95% CI: 1.05-1.48), Pitt score (aOR: 1.72; 95% CI: 1.35-2.17), and lymphocyte count ≤500 cells/μL at presentation (aOR: 3.16; 95% CI: 1.42-7.06) predicted therapeutic failure at day 30. Carbapenem monotherapy (68.6%, primarily meropenem) was the most frequent active therapy, followed by BLBLI monotherapy (10.8%, mostly piperacillin-tazobactam). Propensity score (PS)-adjusted models revealed no significant impact of the choice of active therapy (carbapenem-containing vs any other regimen, BLBLI- vs carbapenem-based monotherapy) within the first 72 hours on any of the study outcomes.

CONCLUSIONS

Our data suggest that active therapy based on BLBLI may be as effective as carbapenem-containing regimens for ESBL-E BSI secondary to UTI in the specific population of KTR. Potential residual confounding and unpowered sample size cannot be excluded (ClinicalTrials.gov identifier: NCT02852902).