Epidemiology and risk factors for ureteral stent-associated urinary tract infections in non-transplanted renal patients: a systematic review of the literature

A new technique for the treatment of ureteric stricture after kidney transplantation

OBJECTIVE

To evaluate the safety and effectiveness of endoscopic treatments with Allium® metal ureteric stent (AMUS) for ureteric strictures after kidney transplantation (KT).

PATIENTS AND METHODS

In a prospective manner, we gathered clinical data from 68 patients who underwent endoscopic treatments with AMUS for ureteric strictures after KT between January 2019 and March 2022. The definition of surgical success was the unobstructed drainage of the AMUS, or in cases where there was AMUS migration, occlusion or encrustation and subsequently removed, there is no worsening of renal hydronephrosis in the patient during the follow-up period.

RESULTS

Based on the specific circumstances of the ureteric strictures, three distinct types of surgery were selected for treatment. The overall success rate of endoscopic treatments for ureteric strictures following KT was 90% (61/68) during a follow-up period of 1 year. Surgical complications included haematuria (18%), pain (10%), urinary tract infections (7.4%), and lower urinary tract symptoms (7.4%). The incidences of stent migration, occlusion, and encrustation were 10%, 2.9%, and 1.5%, respectively. Postoperatively, significant improvements were observed in various parameters. At 1 month after surgery, there was a notable decrease in blood creatinine levels (105.5 vs 90.4 mol/L), urea nitrogen levels (6.6 vs 5.4 mmol/L), and hydronephrosis volume (64.4 vs 43.9 mL). Additionally, the serum estimated glomerular filtration rate increased from 49.5 to 64.4 mL/min/1.73 m2. The follow-up results of patients at 1 year after surgery were similar to those observed at 1 month after surgery.

CONCLUSIONS

Systemic endoscopic treatments with AMUS were found to be safe and effective for ureteric strictures after KT with short-term follow-ups. This technique offers a novel option for the treatment of post-KT strictures.

Asymptomatic bacteriuria prior to partial and radical nephrectomy: To screen or not to screen? Results from the national and multicenter TOCUS database

INTRODUCTION

In the era of increased bacterial resistance, the main strategy is to reduce the prescription of antibiotics when possible. Nowadays, it is highly recommended to screen for asymptomatic bacteriuria (ABU), prior to urological surgery with potential mucosal breach or urine exposure. Screening and treating urinary colonization is a strategy widely adopted before radical and partial nephrectomy but without any evidence. Our main end point in this study is to analyze the relationship between preoperative urine culture and the risk of postoperative febrile urinary tract infection (UTI) or surgical-site infection (SSI) in partial or radical nephrectomy patients.

METHODS

We conducted a multicenter retrospective cohort study between January 2016 and January 2023 in 11 French tertiary referral hospitals (TOCUS database). We collected the data for 269 patients including several pre-, intra-, and post-operative variables that could potentially increase the risk of postoperative UTI and SSI including preoperative urinary culture results.

RESULTS

The incidence rate of postoperative UTI and SSI was 8.9% in our study. After conducting a logistic multivariate analysis, a propensity score matching analysis, and a subgroup analysis, we found no significant correlation between the urine culture and the postoperative UTI risk [OR = 1.2 (0.5-2.7) (p = 0.7)]. Only the postoperative non-infectious complications were related to a higher risk of postoperative UTI [OR = 12 (4-37), p < 0.001)].

CONCLUSION

Our research shows that screening and treating for ABU prior to radical or partial nephrectomy seems to be unnecessary to prevent postoperative UTI and SSI.

Metal ureteral stents for ureteral stricture: 2 years of experience with 246 cases

BACKGROUND

Metal ureteral stents (MUS) has gained popularity as an endoscopic treatment alternative for the management of ureteral strictures. The aim of this study was to evaluate the safety, efficacy, and tolerability of MUS for treating ureteral strictures and to identify any factors that could influence the success of this intervention.

METHODS

This study is a prospective analysis of the efficacy and safety of MUS for treating ureteral strictures in a single-center setting. The study enrolled 246 patients who had been diagnosed with ureteral strictures and had undergone MUS placement between January 2019 and July 2021. The patients were followed-up for a duration of 2 years.

RESULTS

The overall success rate of MUS placement was 71.7%. Furthermore, the success rate of ureteral strictures after kidney transplantation (78.2%) was significantly higher than common ureteral strictures (73.0%) or recurrent ureteral strictures (67.6%). Additionally, postsurgery, there was a considerable reduction in hydronephrosis volume (68.9±96.1 vs. 32.1±48.8 cm 3 ), blood creatinine level (103.7±49.8 vs. 94.4±47.5 mol/l) and urea nitrogen level (6.7±7.2 vs. 5.1±2.4 mmol/l). The study also reported that the rate of adverse events associated with MUS was relatively low, included hematuria (7.9%), pain (6.8%), urinary tract infection (6.4%), and lower urinary tract symptoms (5.3%).

CONCLUSIONS

MUS appear to be a safe and effective treatment option for ureteral strictures, with a high success rate and low complication rate. These results have important implications for the management of ureteral strictures and can help guide clinical decision-making in the selection of treatment options.

Successful treatment of ureteral-stent-related fungal ball using fluconazole instillation through a nephrostomy tube

The kidneys are the most common solid organ to be infected by Candida sp. And may occur due to hematogenous spread, ascending infection, or with the presence of stent and nephrostomy tubes. Evidence for treatment is limited to case reports. We successfully cleared a candida infection of a ureteric stent in a 35-year-old diabetic gentleman by instilling 300 mg of fluconazole in 500 mL of normal saline over 8 hours once daily for 7 days via the nephrostomy tube.

Epidemiology and risk factors for febrile ureteral stent-associated urinary tract infections: A prospective observational cohort study

OBJECTIVES

We aimed to determine the incidence and risk factors of febrile ureteral stent-associated urinary tract infections (FUSAUTI).

METHODS

Hospitalized adult patients with ureteral stent (US) placement or exchange were prospectively enrolled. Patients with kidney transplantation of less than one year were excluded. Patients were followed until US removal/exchange or six months after inclusion.

RESULTS

Out of 663 patients included in the study, 48 had at least one FUSAUTI (cumulative incidence 7.24%; 95% confidence interval [CI] 5.39-9.48). The incidence rate of FUSAUTI was 9.04 (95% CI 6.67-12.2) per 10,000 US-days. Ten patients (20.8%) experienced sepsis or septic shock. The most frequently isolated microorganisms were Escherichia coli (38%), Enterococcus spp. (14.5%), Candida spp. (9%) and Pseudomonas aeruginosa (9%). In multivariable logistic regression analysis, female gender, an age adjusted Charlson comorbidity index score> 3, an urethral stent placement concomitant with US placement, and a history of urinary tract infection within three months were significantly associated with a higher risk of FUSAUTI.

CONCLUSION

After US placement, 7.24% of patients developed at least one FUSAUTI and, in a quarter of cases, a serious infection. Urethral stent placement was the only modifiable risk factor identified. Future interventional studies are needed to reduce FUSAUTI in these patients.