Safety of Fluoroquinolones and Cotrimoxazole in Urinary Tract Infections in Older Males

Abstract

Background

Guidelines recommend fluoroquinolones or cotrimoxazole for urinary tract infections in men (UTIm), but safety data in frail older patients remain limited. The aim of this study was to compare the tolerability of these antibiotics in UTIm patients over age 75 years.

Methods

This multicenter retrospective study included patients age ≥75 years who were hospitalized for UTIm in 8 hospitals and treated with oral fluoroquinolone or cotrimoxazole. Adverse events (AEs) during hospitalization were compared.

Results

Among 228 patients (median age, 85 years), 131 (57.4%) received fluoroquinolones and 97 (42.6%) cotrimoxazole. Baseline characteristics were similar. AEs occurred in 29.7% of fluoroquinolone-treated patients vs 48.5% treated with cotrimoxazole (P = .006), leading to treatment discontinuation in 2.3% vs 11.3% (P = .009). Acute kidney injury was observed in 7.2% vs 29.4% (P < .001), metabolic disorders in 7.6% vs 18.6% (P = .023). Other AEs and mortality did not differ significantly. Cotrimoxazole was associated with a doubled risk of AEs (adjusted odds ratio, 2.10; 95% CI, 1.18–3.74; P = .01).

Conclusions

These results suggest a better safety profile of fluoroquinolones than cotrimoxazole in the treatment of UTI in older men. These results need to be confirmed in a prospective design.

Camille Gouraud, Alain Putot, Thibaut Fraisse, Messaline Bermejo, Benjamin Viala, Charlotte Golstein, Nadège Lemarie, Claire Roubaud Baudron, Pauline Caraux-Paz, on Behalf of the Infectious diseases and Geriatrics French Research Group (GInGer), Safety of Fluoroquinolones and Cotrimoxazole in Urinary Tract Infections in Older Males, Open Forum Infectious Diseases, Volume 13, Issue 5, May 2026, ofag271, https://doi.org/10.1093/ofid/ofag271