title: The clinical impact of linezolid susceptibility reporting in patients with vancomycin-resistant enterococci.
abstract: Linezolid remains a mainstay of therapy for vancomycin-resistant enterococci (VREs), but resistance has emerged. We describe a cohort of 20 patients with linezolid-intermediate or resistant VRE (LIRVRE) reported by Etest and disk diffusion testing, 18 of whom demonstrated linezolid susceptibility by agar dilution on further investigation. Patients with reported LIRVRE were matched based on culture site and enterococcal species to patients with linezolid-susceptible VRE (LSVRE) in a 1:3 ratio. Patients with reported LIRVRE developed more nosocomial infections (P = .04), had more central lines placed (P = .04), and underwent more computed tomography scans related to VRE infection (P = .02). Multivariate analysis revealed increased surgical procedures related to VRE infections (P = .008), increased linezolid use during hospital stay (P = .03), and delayed culture and susceptibility results compared with those with LSVRE (P = .006). Therefore, inaccurate detection and reporting of LIRVRE by disk diffusion and Etest is associated with increased patient morbidity and resource use.
authors.affiliation: Department of Pharmacy, Northwestern Memorial Hospital, Chicago, IL 60611, USA. mscheetz@nmh.org
authors.forename: Marc H
authors.initials: MH
authors.lastname: Scheetz
authors.forename: Chao
authors.initials: C
authors.lastname: Qi
authors.forename: Gary A
authors.initials: GA
authors.lastname: Noskin
authors.forename: John R
authors.initials: JR
authors.lastname: Warren
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Postelnick
authors.forename: Michael
authors.initials: M
authors.lastname: Malczynski
authors.forename: Jie
authors.initials: J
authors.lastname: Huang
authors.forename: Teresa R
authors.initials: TR
authors.lastname: Zembower
mesh_terms: D000046:Academic Medical Centers; D000081:Acetamides / Q000494:pharmacology* / Q000627:therapeutic use; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D015331:Cohort Studies; D003428:Cross Infection / Q000473:pathology; D004198:Disease Susceptibility; D024901:Drug Resistance, Multiple, Bacterial; D013293:Enterococcus faecalis / Q000187:drug effects*; D016984:Enterococcus faecium / Q000187:drug effects*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D006801:Humans; D007902:Length of Stay; D000069349:Linezolid; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods*; D008875:Middle Aged; D023303:Oxazolidinones / Q000494:pharmacology* / Q000627:therapeutic use; D012189:Retrospective Studies; D016896:Treatment Outcome; D014640:Vancomycin / Q000494:pharmacology* / Q000627:therapeutic use; D020713:Vancomycin Resistance
chemical_list: D000081:Acetamides; D000890:Anti-Infective Agents; D023303:Oxazolidinones; D014640:Vancomycin; D000069349:Linezolid