Retrospective Analysis to Determine the Optimal Timing to Discontinue Continuous Antibiotic Prophylaxis in Patients with Primary Vesicoureteral Reflux

Background: The management of febrile urinary tract infection (fUTI) in patients with vesicoureteral reflux (VUR) is crucial to prevent renal scarring. Continuous antibiotic prophylaxis (CAP) is the most widely used initial treatment for VUR. However, the optimal duration of CAP is still unclear. We aimed to clarify an appropriate patient population and the optimal timing to discontinue CAP. Methods: We reviewed the records of 247 patients with primary VUR between January 2000 and December 2015. Seventy-two patients who discontinued CAP despite persistent VUR were enrolled. Kaplan-Meier method and Cox proportional hazard model was used in statistical analysis. Results: Following the discontinuation of CAP, fUTI developed in 25 patients after a median of 9 months (range 0–81). VUR resolved spontaneously in 9 out of 47 patients without recurrence during follow-up. Multivariate analysis showed bilateral VUR and duration of CAP of less than 1 year after the last fUTI were significant risk factors for recurrence. Conclusion: Among the risk factors examined, patients administered CAP for less than 1 year after the last fUTI and those with bilateral VUR had significantly more frequent recurrence. Our study suggests that the administration of CAP for more than 1 year after the last fUTI is beneficial in avoiding recurrent fUTI.