Questioning the Addition of Fluoroquinolone on Mortality in Severe Community-Acquired Pneumonia: A multicenter study in Korea

J Microbiol Immunol Infect. 2025 May 9:S1684-1182(25)00086-6. doi: 10.1016/j.jmii.2025.04.004. Online ahead of print.

Abstract

Background: The use of fluoroquinolone (FQ) combination therapy as empirical treatment for severe community-acquired pneumonia (sCAP) remains unclear. In this study, we aimed to evaluate its clinical impact.

Methods: This retrospective study was conducted in seven large university-affiliated hospitals in Korea. It included adult inpatients (age ≥19 years) diagnosed with sCAP between March 2020 and February 2023, identified through third-ranked pneumonia codes, who received anti-pseudomonal beta-lactam (APBL) and/or FQ within 24 h of admission. Propensity-score matching compared monotherapy and combination therapy outcomes.

Results: Of 588 enrolled patients with sCAP, 177 per group were analyzed post-matching. No significant differences were found in all-cause in-hospital mortality (36.7 % vs. 36.2 %, P = 0.917), in-hospital mortality from pneumonia aggravation (29.9 % vs. 30.5 %, P = 1.000), or 30-day mortality (26.6 % vs. 29.4 %, P = 0.251). FQ combination therapy did not affect 30-day mortality significantly (P = 0.489). None of the variables significantly influenced 30-day mortality, pneumonia recurrence within 28 days, total antibiotic duration, or hospital stay.

Conclusions: In patients with sCAP, outcomes did not differ significantly between APBL monotherapy and FQ combination therapy. This suggests that even in severe CAP, an individualized treatment strategy based on the causative agent may be more appropriate than indiscriminate combination therapy.

Keywords: Anti-bacterial agent; Community-acquired pneumonia; Fluoroquinolone; Mortality.