Survival benefit of beta-lactam plus macrolide combined therapy versus beta-lactam plus quinolones in hospitalized community-acquired pneumonia

Background: Guidelines do not state a specific advantage regarding the addition of macrolides or quinolones to beta-lactams in empirical combined antibiotic therapy. But little is known if there exists a survival benefit of the different regimes. We aim to evaluate the impact in mortality of two different guidelines-recommended combined antibiotic therapies. Methods: We stratified patients from a prospective multicenter cohort according to the use of combined antibiotic treatment [beta-lactam plus macrolide (B+M) or beta-lactam plus quinolones (B+Q)]. Demographic, clinical, radiographic, microbiologic and complication characteristics were analyzed. Outcomes were analyzed performing a multivariate analysis using the different antibiotic combinations as the dependent variable. Results: From an initial population of 2,013 patients, 758 (37.6%) were treated with combination therapy: B+M, 575 (75.9%); B+Q 183 (24.1%). Comorbities were more frequent in patients treated with B+Q but this was not confirmed by multivariate analysis. B+M showed a protective effect regarding the development of acute kidney injury (OR 0.51, 95%CI 0.28-0.93) and ICU admission (OR 0.43, 95%CI 0.22-0.85). Mortality was significantly higher in B+Q group (11.6 vs 4.6, p Conclusions: Empiric combination antibiotic therapy with beta-lactams plus macrolides is associated with better survival than beta-lactam plus quinolones in CAP. Randomized control trials are needed to confirm this finding.