Clinical Outcomes Associated With Linezolid Resistance in Leukemia Patients With Linezolid-Resistant Bacteremia

Background: Coagulase-negative staphylococci, including , are the most common cause of bloodstream infection in cancer patients. Linezolid resistance is increasingly identified in but whether such resistance alters the clinical course of infections is unknown. The purpose of this study was to assess the clinical impact of linezolid resistance in leukemia patients with bloodstream infection.

Methods: This was a retrospective, single-center cohort study of all adult leukemia patients with bacteremia treated with empiric linezolid between 2012 and 2015. The primary end point was adverse clinical outcome on day 3, defined as a composite of persistent bacteremia, fever, intensive care unit admission, or death. Fourteen- and 30-day mortality were also assessed.

Results: Eighty-two unique leukemia patients with were identified. Linezolid resistance was identified in 33/82 (40%). Patients with linezolid-resistant were significantly more likely to have persistent bacteremia (41% vs 7%; adjusted relative risk [aRR], 5.15; 95% confidence interval [CI], 1.63-16.30; = .005); however, adverse short-term clinical outcomes overall were not more common among patients with linezolid-resistant (61% vs 33%; aRR, 1.46; 95% CI, 0.92-2.32; = .108). No differences were observed in 14- or 30-day mortality.

Conclusions: Leukemia patients with linezolid-resistant bacteremia who were treated with linezolid were significantly more likely to have persistent bacteremia compared with those with linezolid-sensitive isolates. Interventions to limit the clinical impact of linezolid-resistant are warranted.