Safety of fluoroquinolones and cotrimoxazole in urinary tract infections in older males

Objectives 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 75 years. Participants and Methods This multicentre retrospective study included patients ≥75 years hospitalized for UTIm in 8 hospitals and treated with oral fluoroquinolone or cotrimoxazole. Adverse events (AEs) during hospitalization were compared. Results Among 228 patients included (median age 85), 131 (57.4%) received fluoroquinolones and 97 (42.6%) cotrimoxazole. Baseline characteristics were similar. AEs occurred 29.7% of fluoroquinolone-treated patients versus 48.5% with cotrimoxazole (p=0.006), leading to treatment discontinuation in 2.3% vs 11.3% (p=0.009). Acute kidney injury was observed in 7.2% vs 29.4% (p<0.001); metabolic disorders in 7.6% vs 18.6% (p=0.023). Other AEs and mortality did not differ significantly. Cotrimoxazole was associated with a doubled risk of AEs (adjusted OR 2.10 [1.18–3.74], p=0.01). 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.