Predicting Renal Outcomes in Children With Anterior Urethral Valves: A Systematic Review

Abstract

Prognostic information is limited on children with congenital anterior urethral valves or a diverticulum. We reviewed the literature and examined our clinical database to identify clinical features predicting a poor renal outcome, defined as azotemia, renal failure or death. We reviewed 97 English language studies of patients 18 years old or younger. Seven patients from our institutions were also included in analysis. After data abstraction we used multivariate models to define factors associated with outcomes of interest. We identified 239 male patients with anterior urethral valves, of whom 139 had adequate data available for study inclusion. Of these patients 108 (78%) had normal renal function after treatment. On bivariate analysis vesicoureteral reflux (OR 22.4, p <0.0001), pretreatment azotemia (OR 17.1, p <0.0001), urinary tract infection (OR 3.3, p = 0.006), hydronephrosis (OR 10.0, p = 0.0004) and bladder trabeculation (OR 7.3, p = 0.01) were associated with renal failure or death while treatment method (p = 0.9), obstruction type (valve vs diverticulum, p = 0.4) and valve location (p = 0.6) were not. After adjusting for other factors only pretreatment azotemia (p = 0.0005) and vesicoureteral reflux (p = 0.01) remained associated with renal failure and/or death with a trend toward significance for urinary tract infection (p = 0.06). When all 3 factors were present, the odds of a poor renal outcome increased 25-fold (p = 0.005). Congenital anterior urethral obstruction in children has a generally good prognosis but may occasionally result in a poor renal outcome. The combination of pretreatment azotemia, vesicoureteral reflux and urinary tract infection is highly predictive of a poor renal outcome.