title: Incidence, risk factors, and outcomes for Enterococcus spp. blood stream infections: a population-based study.
abstract: BACKGROUND
  Enterococci are a clinically significant cause of bloodstream infections (BSI), particularly in the nosocomial setting. The purpose of this study was to characterize the incidence, risk factors for acquisition, microbiological characteristics and mortality of enterococcal BSI within the well-defined population of a large Canadian health region.
  
  
  METHODS
  Surveillance for all episodes of enterococcal BSI occurring among residents of the Calgary Health Zone (population 1.2 million) between 2000 and 2008 was conducted using an electronic surveillance system. Clinical features, microbiology, and outcomes were obtained.
  
  
  RESULTS
  A total of 710 incident episodes of enterococcal BSI were identified for an annual incidence of 6.9 episodes per 100,000; the incidences of E. faecalis and E. faecium BSI were 4.5, and 1.6 per 100,000, respectively. Enterococcus faecalis infections were associated with a urinary focus, genitourinary malignancy, and abnormal genitourinary anatomy. E. faecium infections were associated with a gastrointestinal focus. Resistance to ampicillin, vancomycin and ciprofloxacin was higher in E. faecium infection. The overall case fatality rate was 22.8%, and was higher for E. faecium infection.
  
  
  CONCLUSIONS
  This is the second population-based study to assess the risk factors for enterococcal BSI and compare the characteristics of infection with E. faecalis and E. faecium. Results suggest that BSI with E. faecalis and E. faecium should be regarded as two clinically different entities with unique sets of risk factors and microbiologic characteristics.
authors.affiliation: Department of Medicine.
authors.forename: E O
authors.initials: EO
authors.lastname: Billington
authors.affiliation: Department of Medicine.
authors.forename: S H
authors.initials: SH
authors.lastname: Phang
authors.affiliation: Microbiology and Infectious Diseases; Calgary Laboratory Services, Calgary, AB CANADA.
authors.forename: D B
authors.initials: DB
authors.lastname: Gregson
authors.affiliation: Microbiology and Infectious Diseases; Calgary Laboratory Services, Calgary, AB CANADA.
authors.forename: J D D
authors.initials: JD
authors.lastname: Pitout
authors.affiliation: Microbiology and Infectious Diseases; Calgary Laboratory Services, Calgary, AB CANADA.
authors.forename: T
authors.initials: T
authors.lastname: Ross
authors.affiliation: Department of Medicine; Microbiology and Infectious Diseases; Calgary Laboratory Services, Calgary, AB CANADA.
authors.forename: D L
authors.initials: DL
authors.lastname: Church
authors.affiliation: Department of Medicine; Community Health Sciences; Critical Care Medicine, The University of Calgary, Calgary, AB CANADA.
authors.forename: K B
authors.initials: KB
authors.lastname: Laupland
authors.affiliation: Department of Medicine; Microbiology and Infectious Diseases. Electronic address: mdparkin@ucalgary.ca.
authors.forename: M D
authors.initials: MD
authors.lastname: Parkins
mesh_terms: D000368:Aged; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D002170:Canada; D024881:Drug Resistance, Bacterial; D016983:Enterococcus / Q000187:drug effects / Q000302:isolation & purification; D013293:Enterococcus faecalis / Q000187:drug effects / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000187:drug effects / Q000302:isolation & purification; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
keywords: Enterococcus faecalis; Enterococcus faecium; VRE; bacteremia; bacterial infections; outcomes; population-based