Intravesical Gentamicin for Prevention of Recurrent Urinary Tract Infections in Patients With Neurogenic Lower Urinary Tract Dysfunction Performing Intermittent Catheterization: A Systematic Review

INTRODUCTION: Patients with neurogenic lower urinary tract dysfunction (NLUTD) performing clean intermittent catheterization (CIC) are at increased risk of recurrent urinary tract infections (rUTIs). Oral antimicrobial prophylaxis has limited efficacy and fosters resistance. Intravesical gentamicin (IVG) has emerged as an alternative, but evidence remains limited and heterogeneous. This systematic review evaluated the efficacy and safety of IVG for rUTI prevention in adults with NLUTD and summarized reported instillation protocols and additional clinically relevant outcomes. METHODS: A systematic review was performed according to PRISMA guidelines. PubMed, Embase, Scopus, and the Cochrane Library were searched for English-language articles published up to April 2025 assessing IVG efficacy and/or safety in adults with NLUTD. RESULTS: Four studies (two prospective, two retrospective) comprising 130 patients met inclusion criteria. IVG was most often administered as 80 mg in 20 mL saline, instilled during the final catheterization and left to dwell overnight. Across studies, IVG reduced rUTI frequency by 83%-89.9%, decreased oral antibiotic use by 71.4%, and lowered the prevalence of multidrug-resistant bacteria. The overall safety was 94.2%. Mild adverse events occurred in 5.8%-21.7% of cases (mainly diarrhea or fungal infections). No serious adverse events were reported. CONCLUSION: Current evidence supports IVG as a safe and effective prophylactic strategy for preventing rUTIs in NLUTD patients performing CIC. However, the small number of studies, heterogeneous protocols, and absence of randomized controlled trials underscore the need for high-quality research to define standardized regimens and inform broader clinical adoption.