Assessing the Utility of Tamsulosin in Delaying Progression to Clean Intermittent Catheterization and End-stage Renal Disease in Patients With Posterior Urethral Valves: Are We Postponing the Inevitable?

Long-Term Kidney Outcomes in Children with Posterior Urethral Valves: A Population-Based Cohort Study

Key Points

Background

Posterior urethral valves represent the most common cause of lower urinary tract obstruction in male infants (approximately 1/4000 live births). Long-term kidney outcomes of posterior urethral valves remain uncertain. We aimed to determine the time-varying risk of major adverse kidney events (MAKE) following children with posterior urethral valves into adulthood.

Methods

A population-based retrospective cohort study of all male children (<2 years) diagnosed with posterior urethral valves between 1991 and 2021 in Ontario, Canada. Comparator cohorts were (1) male general population and (2) male children with pyeloplasty (both <2 years). The primary outcome was MAKE (death, long-term KRT [dialysis or kidney transplant], or CKD). Time to MAKE was analyzed using multivariable-adjusted Cox proportional hazards models. We censored for provincial emigration or administrative censoring (March 31, 2022).

Results

We included 727 children with posterior urethral valves, 855 pyeloplasty comparators, and 1,013,052 general population comparators. The median follow-up time was 16.6 years (Q1–3, 8.6–24.5) overall. Throughout follow-up, 32% of children with posterior urethral valves developed MAKE versus 1% of the general population and 6% of pyeloplasty comparators. Their adjusted hazard ratio for MAKE was 36.6 (95% confidence interval, 31.6 to 42.4) versus the general population. The risk of developing MAKE declined over the first 5 years after posterior urethral valves diagnosis but remained elevated for >30-year follow-up. Children with posterior urethral valves were also at higher risk of death, CKD, long-term KRT, hypertension, and AKI than the general population or pyeloplasty comparators.

Conclusions

Children with posterior urethral valves are at higher risk of adverse long-term kidney outcomes well into adulthood.

Assessing safety and tolerability of super selective alpha-1 adrenergic blockers in infants under 3 years: Insights from a single-center study on lower urinary tract obstruction (LUTO)

BACKGROUND

Little is known about alpha blocker use in young children, particularly in those with lower urinary tract obstruction (LUTO). Therefore, we aimed to assess the safety and tolerability of selective alpha-blockers in children under 3 years of age with LUTO.

METHODS

A prospectively-collected database captured 93 patients born between 12/2005 and 01/2023. Assessed data included baseline characteristics, ultrasound features, blood pressure (BP), side effects and creatinine values. Primary outcome was side effects or discontinuation of alpha-blockers. Secondary outcomes were BP parameters, growth, and kidney function. Data are shown as median with interquartile range (IQR), Odds Ratio (OR) with 95% CI and mean value with standard deviation (SD).

RESULTS

A total of 33 patients less than 3 years of age were started on alpha-blockers at 16.8 ± 11.8 months and followed for 48.9 ± 40.5 months. At last follow-up, no significant effect on systolic/diastolic BP percentiles (p > 0.9 and p > 0.9), creatinine levels (p > 0.9). Weight percentiles increased to the last follow-up (37.8 ± 33.2 vs. 53.6 ± 32.9, p = 0.0133) while height percentiles increased from 28 to 100 days to last follow-up (12.9 ± 18.3 vs. 39.6 ± 35.2, p=0.001). Four patients discontinued alpha-blockers; however, no side-effects were reported during the study period.

CONCLUSIONS

No severe clinical or systemic side effects were observed, demonstrating safety and tolerability in young children with LUTO. Although alpha-blockers did not significantly improve kidney function in short term follow-up, and failure to thrive was not observed in these children. Additional studies with more patients are required to assess the optimal dosing and timing leading to maximal benefits for these infants.

Fetal urinary tract dilation: What to tell the parents

Urinary tract dilation (UTD), which refers to the abnormal dilation of the urinary collection system, is the most common finding on prenatal ultrasound and presents with varying severity, presentation, etiology, and prognosis. Prenatal classification and risk stratification aim to prevent postnatal complications, such as urinary tract infections and further kidney dysfunction. Parents expecting a child with UTD should be counseled by a multidisciplinary team consisting of maternal-fetal medicine specialists, and pediatric urology and nephrology providers. This review summarizes the key points in the diagnostic evaluation and management during the prenatal and initial postnatal period, focusing on the information that should be provided to future parents. We address frequently asked parental questions and concerns that our multidisciplinary clinical practice faces.