Pilot randomized, placebo controlled trial to investigate the effect of antibiotic prophylaxis on the rate of urinary tract infection in infants with prenatal hydronephrosis.

We determined the feasibility of a clinical trial of continuous antibiotic prophylaxis to prevent urinary tract infections in children with prenatal hydronephrosis. We piloted a blinded, randomized, placebo controlled study of the urinary tract infection rate in infants with grades III-IV prenatal hydronephrosis at our institution between August 2010 and June 2013. Study exclusion criteria were grades I/II prenatal hydronephrosis, vesicoureteral reflux, duplication anomalies and age at randomization greater than 5 months. Prospectively collected feasibility data were obtained on eligibility, enrollment status, adherence to followup schedule, and medication and protocol compliance. Of 301 screened patients 220 (73.1%) were ineligible for analysis and 2 (1%) missed the randomization window. Of the remaining 81 (26.9%) eligible patients 46 were enrolled (56.8%), 29 refused (39.5%) and consent is pending in 1 (1.2%). Reasons for declining participation included parental preference for or against continuous antibiotic prophylaxis and a lack of interest in participating in clinical research. Of 46 enrolled patients 29 (63%) completed the trial, 12 (26.1%) are still in followup and 5 (10.9%) withdrew. Of the 314 medication logs dispensed 263 were returned for a 95% mean medication compliance rate. Based on the results of our pilot study a realistic recruitment rate for this group of patients is established, making a definitive trial of this topic feasible. However, due to the low number of eligible patients multicenter collaboration is critical to address the effect of continuous antibiotic prophylaxis on the urinary tract infection rate in this population. After study enrollment high medication and followup compliance can be expected.