Meta-analysis of vancomycin versus linezolid in pneumonia with proven methicillin-resistant Staphylococcus aureus

American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines suggest that linezolid (LZD) is preferred over vancomycin (VCM) for treating methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. We conducted a systematic review and comparative meta-analysis to compare VCM and LZD efficacy against proven MRSA pneumonia.We searched EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed up to November 2019. The outcomes of the meta-analysis were mortality, clinical cure, microbiological evaluation, and adverse events.Seven randomized controlled trials (RCTs) with a total of 1239 patients and eight retrospective cohort or case-control studies (CSs) with a total 6125 patients were identified. Clinical cure and microbiological eradication rates were significantly increased in patients treated with LZD in RCTs (clinical cure: risk ratio (RR) = 0.81, 95% confidential interval (CI) = 0.71-0.92; microbiological eradication: RR = 0.71, 95% CI = 0.62-0.81) and CSs (clinical cure: odds ratio (OR) = 0.35, 95% CI = 0.18-0.69). However, mortality was comparable between patients treated with VCM and LZD in RCTs (RR = 1.08, 95% CI = 0.88-1.32) and CSs (OR = 1.20, 95% CI = 0.94-1.53). Likewise, there was no significant difference in adverse events between VCM and LZD in CSs (thrombocytopenia: OR = 0.95, 95% CI = 0.50-1.82; nephrotoxicity: OR = 1.72, 95% CI = 0.85-3.45).According to our meta-analysis of RCTs and CSs conducted worldwide, we found robust evidence to corroborate the IDSA guidelines for the treatment of proven MRSA pneumonia.