Kidney function and transplants in prune belly syndrome: a scoping review.

BACKGROUND: Children with prune belly syndrome (PBS) are at higher risk of developing kidney dysfunction and requiring kidney replacement therapy (KRT). While studies have described surgical and survival outcomes in these populations, there has yet to be a focused synthesis of evidence regarding kidney outcomes in this population. Here, the focus of this scoping review was to highlight knowledge gaps and report standards on kidney outcomes in PBS of all ages. METHODS: Following scoping review methodology, EMBASE, MEDLINE, and Scopus were searched for peer-reviewed literature that describe kidney outcomes in PBS. All studies with a broad set of kidney outcomes (such as kidney function measures, chronic kidney disease (CKD), KRT and associated outcomes) were included. Findings were summarized and qualitatively synthesized. RESULTS: Of the 436 unique records identified, 25 were included for synthesis. A total of 17 studies (441 patients) reported on kidney insufficiency outcomes, with an estimated prevalence of CKD ranging from 8 to 66%. A total of 15 studies (314 patients) described KRT, primary kidney transplant, and outcomes. Of these, the age for KRT ranged from 4 to 21 years, and graft survival ranged from 22 to 87% by last follow-up (range 1.3-27 years). CONCLUSIONS: There is significant variability in studies reporting kidney outcomes in PBS which limits meaningful synthesis. There is a need for future studies with comprehensive reporting of confounders and drivers for kidney insufficiency in PBS.

H2S supplementation: A novel method for successful organ preservation at subnormothermic temperatures.

Renal transplantation is the preferred treatment for end-stage renal disease. Currently, there is a large gap between the supply and demand for transplantable kidneys. The use of sub-optimal grafts obtained via donation after cardiac death (DCD) is on the rise. While static cold storage (SCS) in University of Wisconsin (UW) solution on ice (4°C) is the clinical standard of care for renal graft preservation, cold storage has been associated with negative graft outcomes. The alternative, normothermic machine perfusion, involves mechanical perfusion of the organ at physiological or normothermic temperature (37°C) and this technique is expensive, complicated and globally inaccessible. As such, simpler alternatives are of interest. Preliminary results revealed that UW solution is more protective at 21°C than 37°C and subnormothermic preservation is of interest because it may facilitate the use of existing solutions while preventing cold injury. We have previously shown that SCS in UW solution supplemented with mitochondria-targeted H2S donor AP39 improves renal graft outcomes. As such, it was hypothesized subnormothermic preservation at 21°C with AP39 will also improve renal outcomes. Using an in vitro model of hypoxia and reoxygenation, we found that treating porcine tubular epithelial cells with UW+5 µM AP39 during 18 h hypoxia at 21°C significantly increased renal tubular epithelial cell viability after 24 h of reoxygenation at 37°C compared to UW alone. Also, AP39-supplemented UW solution was significantly more cytoprotective during hypoxia at 21°C than hypoxia at 37°C, regardless of AP39 concentration. Using an ex vivo DCD organ preservation model, we found that DCD porcine kidneys stored for 24 h in UW+200 nM AP39 at 21°C showed significantly lower tissue necrosis than DCD porcine kidneys preserved using SCS in UW solution, the clinical standard of care. Overall, our findings suggest that exogenous H2S supplementation improves the viability of the gold standard organ preservation solution, UW solution, for subnormothermic preservation at 21°C.

The role of circumcision in preventing urinary tract infections in children with antenatal hydronephrosis: Systematic review and meta-analysis.

INTRODUCTION: Circumcision has been reported to reduce the risk of urinary tract infections (UTIs) in boys with antenatal hydronephrosis (HN). Our aim was to compare the incidence of UTIs in circumcised vs. uncircumcised boys with antenatal HN by conducting a systematic review and meta-analysis. STUDY DESIGN: A comprehensive search was performed until December 2022. Comparative studies were evaluated according to Cochrane collaboration recommendations. Assessed measures included: UTIs, continuous antibiotic prophylaxis (CAP) use, renal outcomes, and circumcision complications. Odds ratios (OR) and mean difference with 95% confidence interval (CI) were extrapolated from available data. Random-effects meta-analysis were performed. RESULTS: Twenty-three studies describing 9093 boys with antenatal HN were identified, including 4677 uncircumcised and 4416 circumcised boys. Overall effect estimates demonstrate that circumcised boys have significantly reduced odds of developing any UTI [OR 0.26, 95%CI 0.21, 0.32; p < 0.001]]. In addition, there a significantly reduced odds of developing UTI when circumcised and on CAP [OR 0.19, 95% CI 0.13, 0.30; p < 0.001]. When stratifying by etiology, circumcision reduced the odds of UTI in boys with isolated HN [OR 0.33, 95% CI 0.16, 0.68; p = 0.003], vesicoureteral reflux [OR 0.23, 95% CI 0.13, 0.42; P < 0.00001], or with posterior urethral valves [OR 0.29, 95% CI 0.13, 0.64; p = 0.002]. DISCUSSION: Circumcision reduces the incidence of UTIs in boys with antenatal HN. This review is limited by the varied definitions of UTIs and inconsistent reporting on HN etiology, renal outcomes, and circumcision complications. CONCLUSIONS: Circumcision should be considered in boys with antenatal HN to prevent the risk of developing UTI. Further research is warranted to individualize the prophylactic role of circumcision for patients with HN.

Primary ablation versus urinary diversion in posterior urethral valve: Systematic review and meta-analysis.

PURPOSE: To determine differences in long-term kidney and bladder outcomes in boys with posterior urethral valves (PUV) managed by a primary valve ablation or primary urinary diversion. MATERIALS AND METHODS: A systematic search was performed in March 2021. Comparative studies were evaluated according to Cochrane collaboration recommendations. Assessed measures included kidney outcomes (chronic kidney disease, end-stage renal disease, kidney function) and bladder outcomes. Odds ratios (OR) and mean difference (MD) with 95% confidence interval (CI) were extrapolated from available data for quantitative synthesis. Random-effects meta-analysis and meta-regression were performed according to study design, and potential covariates were assessed with subgroup analysis. The systematic review was prospectively registered on PROSPERO (CRD42021243967). RESULTS: Thirty unique studies describing 1547 boys with PUV were included in this synthesis. Overall effect estimates demonstrate that patients undergoing primary diversion have significantly increased odds of developing renal insufficiency [OR 0.60, 95% CI 0.44, 0.80; p < 0.001]. However, when adjusting for baseline kidney function between intervention groups, there was no significant difference in long term kidney outcomes [p = 0.09, 0.35], or the development of bladder dysfunction or requiring clean-intermittent catheterization with primary ablation rather than diversion [OR 0.89, 95% CI 0.49, 1.59; p = 0.68]. CONCLUSIONS: Current low-quality evidence suggests that medium-term kidney outcomes in children are similar between primary ablation and primary diversion after adjusting for baseline kidney function, while bladder outcomes are highly heterogenous. Further research with covariate control is warranted to investigate sources of heterogeneity. LEVEL OF EVIDENCE: Level III.

Predictors of urosepsis in struvite stone patients after percutaneous nephrolithotomy.

PURPOSE: This study aims to identify clinical factors that may predispose struvite stone patients to urosepsis following percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A retrospective review was conducted on patients who received PCNL for struvite stones. The Systemic Inflammatory Response Syndrome (SIRS) criteria and quick-Sepsis Related Organ Failure Assessment (q-SOFA) criteria were used to identify patients who were at an increased risk for urosepsis. Statistical analysis was performed using Fisher's exactness test, Wilcoxon rank test, and logistic regression. RESULTS: Chart review identified 99 struvite stone patients treated with PCNL. Post-operatively, 40 patients were SIRS positive (≥2 criteria) and/or q-SOFA positive (score ≥2). Using SIRS as an approximation for urosepsis, longer operative times (p<0.001), higher pre-operative white blood cell counts (p=0.01), greater total stone surface area (p<0.0001), and pre-operative stenting (OR, 5.75; p=0.01) were identified as independent risk factors for urosepsis. Multivariate analysis demonstrated pre-operative stenting (OR, 1.46; p=0.01) to be a risk factor. With q-SOFA, univariable analysis found that antibiotic use within 3 months prior to a PCNL (OR, 4.44; p=0.04), medical comorbidities (OR, 4.80; p=0.02), longer operative times (p<0.001), lengthier post-operative hospitalization (p<0.01), and greater total stone surface area (p<0.0001) were risk factors for urosepsis. Multivariate analysis revealed that bladder outlet obstruction (OR, 2.74; p<0.003) and pre-operative stenting (OR, 1.27; p=0.01) significantly increased odds of being q-SOFA positive. CONCLUSIONS: Several risk factors for urosepsis following PCNL for struvite stones have been identified. These risk factors should be taken into consideration in peri-operative care to mitigate the risks of urosepsis.