LAUSR

BACKGROUND Linezolid is an antibiotic frequently used to treat vancomycin-resistant enterococcal infections. Vancomycin-susceptible Enterococcus faecalis can develop resistance to linezolid in environments with excessive linezolid use. AIM To define risk factors and outcome associated with the acquisition of linezolid-resistant Enterococcus faecalis. METHODS A retrospective study of cases and controls was designed involving patients hospitalized from January 2014 to October 2017 at the Hospital Civil de Guadalajara "Fray Antonio Alcalde." Fifty patients with a culture positive for Enterococcus faecalis resistant to linezolid and 100 controls hospitalized in the same room and date as the cases were included. Clinical and demographic data were collected and analyzed. RESULTS Risk factors for the presence of E. faecalis resistant to linezolid included prior linezolid use (OR 6.7), prior clindamycin use (OR 6.7), and previous surgery (OR 5.7). The mortality rate for cases was 18% on the LREF versus 9% for controls. CONCLUSIONS Linezolid-resistant Enterococcus faecalis has emerged and spread in our hospital, an environment in which linezolid use is considerable. Risk factors for linezolid-resistant E. faecalis are prior antibiotic use, including linezolid, and previous surgery.