Background: Empirical broad-spectrum antibiotics including anti-MRSA therapy are often selected because of concerns for resistant organisms. However, the outcomes of empirical anti-MRSA therapy among patients with pneumonia are unknown.
Study design: A national retrospective multicenter cohort study of hospitalizations for pneumonia.
Setting: This cohort study included 88,605 hospitalizations for pneumonia in the Veterans Health Administration health care system during 2008-2013, in which patients received either anti-MRSA or standard therapy for community-onset pneumonia.
Synopsis: Among 88,605 hospitalizations for pneumonia, 38% of the patients received empirical anti-MRSA therapy within the first day of hospitalization and vancomycin accounted for 98% of the therapy. The primary outcome was 30-day all-cause mortality after adjustment for patient comorbidities, vital signs, and laboratory results. Three treatment groups were studied: patients receiving anti-MRSA therapy (vancomycin hydrochloride or linezolid) plus guideline-recommended standard antibiotics (beta-lactam and macrolide or tetracycline hydrochloride, or fluoroquinolone); patients receiving anti-MRSA therapy without standard antibiotics; and patients receiving standard therapy alone. There was no mortality benefit of empirical anti-MRSA therapy versus standard antibiotics, even in those with risk factors for MRSA or in those whose clinical severity warranted admission to the ICU. Empirical anti-MRSA treatment was associated with greater 30-day mortality compared with standard therapy alone, with an adjusted risk ratio of 1.4 (95% confidence interval, 1.3-1.5) versus empirical anti-MRSA treatment plus standard therapy and 1.5 (1.4-1.6) versus empirical anti-MRSA treatment without standard therapy.
Bottom line: Empirical anti-MRSA therapy does not improve mortality and should not be routinely used in patients hospitalized for community-onset pneumonia, even in those with MRSA risk factors.
Citation: Jones BE et al. Empirical anti-MRSA vs. standard antibiotic therapy and risk of 30-day mortality in patients hospitalized for pneumonia. JAMA Intern Med. 2020 Feb 17;180(4):552-60.
Dr. Li is assistant professor of medicine, section of hospital medicine, at the University of Virginia School of Medicine, Charlottesville.