Linezolid as rescue treatment for left-sided infective endocarditis: an observational, retrospective, multicenter study.

The increasing number of resistant bacterial strains in infective endocarditis (IE) emphasizes the need for a constant development of antimicrobials. Linezolid is an oxazolidinone with an effect on Gram-positive cocci. Only a few casuistic reports describe its utilization in the treatment of IE. The objective of this study is to report our experience with linezolid from a large consecutive cohort of IE patients. In a retrospective cohort study, data on 550 consecutive IE patients were collected at two tertiary University Hospitals in Copenhagen, Denmark. The main endpoints were differences in the in-hospital and 12 months post-discharge mortality between IE patients receiving linezolid for a part of the treatment and IE patients receiving conventional treatment. Of the 550 patients enrolled in the study, 38 patients received linezolid treatment and 512 received conventional treatment. Reasons for adding linezolid were antibiotic intolerance (n = 13), nephrotoxicity (n = 5), pharmaceutical interactions (n = 1), inadequate clinical response (n = 14), or inadequate microbial response (n = 5). No significant differences in the cure rate (74 % vs. 71 %, p > 0.05), in-hospital mortality (13 % vs. 14 %, p > 0.05), or post-discharge mortality at 12 months follow-up (26 % vs. 26 %, p > 0.05) were observed. In the current study, we found that linezolid, in general, was well tolerated and associated with the same outcome as in patients with Gram-positive IE treated with other antibiotics.