Antibiotic prophylaxis for urinary tract infections in antenatal hydronephrosis.

BACKGROUND AND OBJECTIVE Continuous antibiotic prophylaxis (CAP) is recommended to prevent urinary tract infections (UTIs) in newborns with antenatal hydronephrosis (HN). However, there is a paucity of high-level evidence supporting this practice. The goal of this study was to conduct a systematic evaluation to determine the value of CAP in reducing the rate of UTIs in this patient population. METHODS Pertinent articles and abstracts from 4 electronic databases and gray literature, spanning publication dates between 1990 and 2010, were included. Eligibility criteria included studies of children <2 years old with antenatal HN, receiving either CAP or not, and reporting on development of UTIs, capturing information on voiding cystourethrogram (VCUG) result and HN grade. Full-text screening and quality appraisal were conducted by 2 independent reviewers. RESULTS Of 1681 citations, 21 were included in the final analysis (N = 3876 infants). Of these, 76% were of moderate or low quality. Pooled UTI rates in patients with low-grade HN were similar regardless of CAP status: 2.2% on prophylaxis versus 2.8% not receiving prophylaxis. In children with high-grade HN, patients receiving CAP had a significantly lower UTI rate versus those not receiving CAP (14.6% [95% confidence interval: 9.3-22.0] vs 28.9% [95% confidence interval: 24.6-33.6], P < .01). The estimated number needed to treat to prevent 1 UTI in patients with high-grade HN was 7. CONCLUSIONS This systematic review suggests value in offering CAP to infants with high-grade HN, however the impact of important variables (eg, gender, reflux, circumcision status) could not be assessed. The overall level of evidence of available data is unfortunately moderate to low.