Laboratory Findings After Urinary Tract Infection and Antimicrobial Prophylaxis in Children With Vesicoureteral Reflux.

It is a common practice to monitor blood tests in patients receiving long-term trimethoprim-sulfamethoxazole (TMP-SMZ) prophylaxis for recurrent urinary tract infections. This multicenter, randomized, placebo-controlled trial enrolled 607 children aged 2 to 71 months with vesicoureteral reflux diagnosed after symptomatic urinary tract infection. Study participants received TMP-SMZ (n = 302) or placebo (n = 305) and were followed for 2 years.