Post-operative Urinary Tract Infection After Pediatric Pyeloplasty: A Multicenter Analysis of Drain Type, Surgical Approach, and Prophylactic Antibiotics.

OBJECTIVES: To determine whether antibiotic prophylaxis at discharge reduces post-operative urinary tract infection (UTI) after pediatric pyeloplasty, and to identify independent predictors of infection. METHODS: We retrospectively reviewed 435 consecutive patients who underwent pyeloplasty at two pediatric urology centers. Post-operative UTI was defined as a culture-proven infection accompanied by fever or urinary symptoms; asymptomatic bacteriuria was excluded. Univariate comparisons used chi-square, Fisher's exact and Mann-Whitney U tests. A multivariable logistic regression model with Wald-based confidence intervals identified independent predictors; collinearity was assessed by variance inflation factors and confirmed by sensitivity, interaction and surgical-era analyses. RESULTS: UTI occurred in 80 patients (18.4%). Drain type was the strongest predictor (p=0.003): 14.8% with double-J stent (DJS) alone, 26.6% with Pippi Salle external stent and 35.1% with combined DJS+PCN. Both externalized configurations remained independent risk factors after adjustment (OR 1.77, 95% CI 1.18-2.68, p=0.006; OR 1.63, 95% CI 1.21-2.21, p=0.001). Pelvic reduction was independently protective (OR 0.52, 95% CI 0.30-0.88, p=0.015). Open surgery was significant on univariate analysis (25.5% vs. 15.0%, p=0.011) but not after adjustment (OR 1.34, p=0.302). Prophylaxis, prescribed in 168 patients (38.6%), showed no association with infection (OR 0.96, p=0.781) and no benefit within any drainage subgroup. Drain duration was not associated with infection. CONCLUSIONS: Drainage configuration, not antibiotic prophylaxis, is the principal determinant of infection risk after pediatric pyeloplasty. Routine post-discharge prophylaxis confers no measurable benefit and may reasonably be withheld in patients managed with an internal stent, supporting a risk-stratified approach guided by drain selection.