Effectiveness of Vancomycin or Beta-Lactam Therapy in Ampicillin-Susceptible Enterococcus spp. Bloodstream Infections:

Background:De-escalation to a beta-lactam improves outcomes for patients with a methicillin-susceptible Staphylococcus aureus bloodstream infection (BSI). Whether a similar strategy is appropriate for enterococcal species is less clear.Objective:To determine whether definitive antibiotic selection affects outcomes for patients with an ampicillin-susceptible enterococcal BSI.Methods:This retrospective cohort study included patients over 18 years of age receiving definitive therapy with vancomycin or a beta-lactam for one or more blood cultures positive for Enterococcus spp. isolates between 2007 and 2014. Survival differences were examined using a Kaplan-Meier curve with log-rank test.Results:One-hundred eighty-six patients received definitive therapy with either vancomycin (n = 45, 24.2%) or a beta-lactam (n = 141, 75.8%). The primary outcome, 30-day all-cause mortality, was not different between groups (6.7% vs 7.1%; P = .992). A post hoc analysis of all-cause mortality 1 year after the index BSI was sig...