Methenamine Hippurate With Cranberry Capsules Versus Cranberry Alone for Urinary Tract Infection Prevention in a Short-Term Indwelling Foley Catheter Population After Urogynecologic Surgery: A Double-Blinded Randomized Controlled Trial.

IMPORTANCE: There is little consensus on an effective nonantibiotic agent for the prevention of urinary tract infection (UTI) after pelvic reconstructive surgery. OBJECTIVE: The aim of the study was to investigate the impact of methenamine hippurate with cranberry capsules on rates of UTI after pelvic reconstructive surgery, among patients requiring short-term catheterization. STUDY DESIGN: In this randomized, double-blinded placebo-controlled trial, patients discharged with a catheter after pelvic reconstructive surgery were approached to participate. Participants were randomized to receive cranberry with methenamine or cranberry with placebo. Primary outcome was number of UTIs treated within 1 week after surgery. Secondary outcomes included incidence of UTIs treated within 6 weeks postoperatively, bacterial species on culture, urinary pH, catheter duration, patient adherence, and satisfaction. A sample size of 88 participants per arm was planned. RESULTS: From June 2019 to July 2021, 185 patients were randomized and 182 analyzed; 89 received placebo and 93 received methenamine. Both groups were similar. Incidence of UTI at 1 week was significantly higher in the placebo group (79.8%) compared with the methenamine group (66.7%; odds ratio, 1.97; 95% confidence interval, 1.01-3.87; P = 0.048). This difference increased by 6 weeks postoperatively (89.9% vs 72.0%; odds ratio, 3.45; 95% confidence interval, 1.51-7.87; P = 0.003). There were fewer pseudomonal UTIs in the methenamine group (P = 0.041). Duration of catheterization and urinary pH were similar. Overall adherence and level of satisfaction was high. CONCLUSIONS: In this high-risk population, methenamine was well tolerated and significantly reduced UTI rates. Methenamine with cranberry should be considered as an effective prophylactic therapy to reduce this common complication after pelvic surgery.