title: Epidemiology, Management, and Risk-Adjusted Mortality of ICU-Acquired Enterococcal Bacteremia.
abstract: BACKGROUND
  Enterococcal bacteremia has been associated with high case fatality, but it remains unknown to what extent death is caused by these infections. We therefore quantified attributable mortality of intensive care unit (ICU)-acquired bacteremia caused by enterococci.
  
  
  METHODS
  From 2011 to 2013 we studied consecutive patients who stayed >48 hours in 2 tertiary ICUs in the Netherlands, using competing risk survival regression and marginal structural modeling to estimate ICU mortality caused by enterococcal bacteremia.
  
  
  RESULTS
  Among 3080 admissions, 266 events of ICU-acquired bacteremia occurred in 218 (7.1%) patients, of which 76 were caused by enterococci (incidence rate, 3.0 per 1000 patient-days at risk; 95% confidence interval [CI], 2.3-3.7). A catheter-related bloodstream infection (CRBSI) was suspected in 44 (58%) of these, prompting removal of 68% of indwelling catheters and initiation of antibiotic treatment for a median duration of 3 (interquartile range 1-7) days. Enterococcal bacteremia was independently associated with an increased case fatality rate (adjusted subdistribution hazard ratio [SHR], 2.68; 95% CI, 1.44-4.98). However, for patients with CRBSI, case fatality was similar for infections caused by enterococci and coagulase-negative staphylococci (CoNS; adjusted SHR, 0.91; 95% CI, .50-1.67). Population-attributable fraction of mortality was 4.9% (95% CI, 2.9%-6.9%) by day 90, reflecting a population-attributable risk of 0.8% (95% CI, .4%-1.1%).
  
  
  CONCLUSIONS
  ICU-acquired enterococcal bacteremia is associated with increased case fatality; however, the mortality attributable to these infections is low from a population perspective. The virulence of enterococci and CoNS in a setting of CRBSI seems comparable.
authors.affiliation: Department of Medical Microbiology Department of Intensive Care Medicine Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht.
authors.forename: David S Y
authors.initials: DS
authors.lastname: Ong
authors.affiliation: Department of Medical Microbiology Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht.
authors.forename: Marc J M
authors.initials: MJ
authors.lastname: Bonten
authors.affiliation: Department of Intensive Care Medicine.
authors.forename: Khatera
authors.initials: K
authors.lastname: Safdari
authors.affiliation: Department of Medical Microbiology Department of Mathematics, Utrecht University.
authors.forename: Cristian
authors.initials: C
authors.lastname: Spitoni
authors.affiliation: Department of Intensive Care Medicine Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht.
authors.forename: Jos F
authors.initials: JF
authors.lastname: Frencken
authors.affiliation: Department of Intensive Care, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: Esther
authors.initials: E
authors.lastname: Witteveen
authors.affiliation: Department of Intensive Care, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Horn
authors.affiliation: Department of Medical Microbiology Department of Intensive Care Medicine Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht.
authors.forename: Peter M C
authors.initials: PM
authors.lastname: Klein Klouwenberg
authors.affiliation: Department of Intensive Care Medicine.
authors.forename: Olaf L
authors.initials: OL
authors.lastname: Cremer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology* / Q000401:mortality; D003428:Cross Infection / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology* / Q000401:mortality; D016983:Enterococcus / Q000302:isolation & purification*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology* / Q000401:mortality; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009426:Netherlands / Q000453:epidemiology; D011446:Prospective Studies
keywords: bacteremia; bloodstream infection; enterococcus; intensive care unit; mortality