title: Emergence of resistance to chloramphenicol among vancomycin-resistant enterococcal (VRE) bloodstream isolates.
abstract: Therapeutic options for vancomycin-resistant enterococcal (VRE) bloodstream infections are extremely limited. Chloramphenicol is effective when VRE isolates are susceptible to this agent. However, longitudinal trends in chloramphenicol-resistant VRE (CR-VRE) are unknown. The possible association between CR-VRE and antibiotic use has not been studied. We analyzed the antimicrobial susceptibility profiles of all VRE blood isolates from 1991-2000 at our institution. We performed a correlational study to examine the relationship between annual hospital-wide use of specific antibiotics and antibiotic classes and CR-VRE prevalence. During the 10-year study period, the prevalence of CR-VRE increased from 0 to 11% ( P< 0.001, trend). CR-VRE prevalence was correlated only with chloramphenicol use (P=0.05 ) and quinolone use (P= 0.01 ). If these trends continue, dependence on newer, more expensive agents will increase. The correlation between both chloramphenicol use and quinolone use and the prevalence of CR-VRE suggests that efforts to preserve the utility of chloramphenicol in VRE infections may depend on optimizing the use of these agents.
authors.affiliation: Department of Medicine, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, 825 Blockley Hall, 423 Guardian Drive, Philadelphia, PA 19104-6021, USA. elautenb@cceb.med.upenn.edu
authors.forename: Ebbing
authors.initials: E
authors.lastname: Lautenbach
authors.forename: Carolyn V
authors.initials: CV
authors.lastname: Gould
authors.forename: Lori A
authors.initials: LA
authors.lastname: LaRosa
authors.forename: Ann Marie
authors.initials: AM
authors.lastname: Marr
authors.forename: Irving
authors.initials: I
authors.lastname: Nachamkin
authors.forename: Warren B
authors.initials: WB
authors.lastname: Bilker
authors.forename: Neil O
authors.initials: NO
authors.lastname: Fishman
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D001769:Blood / Q000382:microbiology; D002701:Chloramphenicol / Q000494:pharmacology* / Q000627:therapeutic use; D024901:Drug Resistance, Multiple, Bacterial; D016983:Enterococcus / Q000187:drug effects* / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D015995:Prevalence; D015363:Quinolones / Q000627:therapeutic use; D020713:Vancomycin Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015363:Quinolones; D002701:Chloramphenicol