title: Response to emerging infection leading to outbreak of linezolid-resistant enterococci.
abstract: Linezolid was approved in 2000 for treatment of gram-positive coccal infections. We performed a case-control study during a hospital outbreak of linezolid-resistant enterococci (LRE) infections, comparing cases of LRE infection (cases) with linezolid-sensitive enterococci infections (controls). Nasal and perirectal swab samples were obtained from all patients in a 1-day point-prevalence survey. We examined antimicrobial drug use and calculated the defined daily dose of linezolid per 1,000 patient-days. Fifteen LRE cases were identified (13 Enterococcus faecalis and 2 E. faecium); 7 were vancomycin-resistant. Compared with controls, case-patients had increased in-hospital mortality rates and lengths of stay. Multivariate analysis identified independent predictors of LRE infection: prior cultures positive for methicillin-resistant Staphylococcus aureus (adjusted odds ratio [AOR] 27), hospitalization duration before index culture (AOR 1.1 per day), and duration of preceding linezolid therapy (AOR 1.1 per day). Linezolid exposure and patient-to-patient transmission appear to be responsible for LRE infections, an important emeraina hospital problem.
authors.affiliation: Tennessee Department of Health, Communicable and Environmental Disease Services, Nashville, Tennessee 37243, USA. marion.kainer@state.tn.us
authors.forename: Marion A
authors.initials: MA
authors.lastname: Kainer
authors.forename: Rose A
authors.initials: RA
authors.lastname: Devasia
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Jones
authors.forename: Bryan P
authors.initials: BP
authors.lastname: Simmons
authors.forename: Kelley
authors.initials: K
authors.lastname: Melton
authors.forename: Susan
authors.initials: S
authors.lastname: Chow
authors.forename: Joyce
authors.initials: J
authors.lastname: Broyles
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Moore
authors.forename: Allen S
authors.initials: AS
authors.lastname: Craig
authors.forename: William
authors.initials: W
authors.lastname: Schaffner
mesh_terms: D000081:Acetamides / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D016022:Case-Control Studies; D015169:Colony Count, Microbial; D021821:Communicable Diseases, Emerging / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D013293:Enterococcus faecalis / Q000187:drug effects*; D016984:Enterococcus faecium / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay; D000069349:Linezolid; D008826:Microbial Sensitivity Tests; D015999:Multivariate Analysis; D023303:Oxazolidinones / Q000494:pharmacology*; D020713:Vancomycin Resistance
chemical_list: D000081:Acetamides; D000890:Anti-Infective Agents; D023303:Oxazolidinones; D000069349:Linezolid