Girls and renal scarring as risk factors for febrile urinary tract infection after stopping antibiotic prophylaxis in children with vesicoureteral reflux.

PURPOSE To clarify the incidence of and risk factors for febrile urinary tract infection in children with persistent vesicoureteral reflux (VUR) after the discontinuation of continuous antibiotic prophylaxis (CAP), retrospective chart review was performed. PATIENTS AND METHODS Among children with primary VUR at 10 years of age or younger at presentation, those who had persistent VUR despite conservative management with CAP and who were subsequently followed after discontinuation of CAP were included. Kaplan-Meier curve and Cox's proportional hazard regression model were used for evaluation of the incidence of and risk factors for febrile urinary tract infection (fUTI) after stopping CAP. RESULTS Among 144 children (99 boys and 45 girls), fUTI developed in 34. The 5-year fUTI-free rate after discontinuation of CAP was 69.4%. On multivariate analyses, girls (p = 0.008) and abnormalities on nuclear renal scans (p = 0.0019), especially focal defect (p = 0.0471), were significant factors for fUTI. Although the fUTI-free rate was not different between children who had no or 1 risk factor, it was significantly lower in children with 2 risk factors than in those with no or 1 risk factor. CONCLUSIONS The present study revealed that girls and abnormal renal scan, especially focal defect, are risk factors for fUTI. Active surveillance without CAP for persistent VUR seems to be a safe option for children with no or 1 risk factor. Prophylactic surgery or careful conservative follow-up may be an option for girls with abnormal renal scan results if VUR persists under CAP.