title: Would earlier microbe identification alter antibiotic therapy in bacteremic emergency department patients?
abstract: BACKGROUND
  Although debate exists about the treatment of sepsis, few disagree about the benefits of early, appropriately targeted antibiotic administration.
  
  
  OBJECTIVE
  To determine the appropriateness of empiric antimicrobial therapy and the extent to which therapy would be altered if the causative organism for sepsis was known at the time of administration.
  
  
  METHODS
  This was a retrospective cohort study, conducted in an academic Emergency Department (ED), on consecutive positive blood cultures between November 1, 2008 and February 1, 2009. Blood cultures and the appropriateness of administered antimicrobial therapy were evaluated. Therapy choices were categorized based on whether or not a physician, complying with antimicrobial guidelines, would have made changes to empiric antibiotic therapy had the causative organism initially been known.
  
  
  RESULTS
  There were 90 positive blood cultures obtained from 84 patients. Of these, 21.1% (n=19) were considered contaminants. The final categorization of empiric antibiotics given in the ED for the remaining blood culture results were: 1) therapy would be changed to narrower-spectrum antibiotics (n=34, 55.7%); 2) therapy would be changed because the organism was not covered (n=13, 21.3%); and 3) therapy would remain the same (n=14, 23.0%). There was 90.2% inter-rater agreement for these classifications (p<0.0001), with a kappa of 0.84. Polymerase chain reaction analysis had a statistically significant advantage (p<0.0001) over Infectious Disease Society of America protocols in facilitating accurate antimicrobial therapies.
  
  
  CONCLUSIONS
  This study confirms the need for more rapid and accurate laboratory methods for bloodstream pathogen identification.
authors.affiliation: Department of Emergency Medicine, University of Arizona, Tucson, Arizona 85724, USA.
authors.forename: Lisa R
authors.initials: LR
authors.lastname: Stoneking
authors.forename: Asad E
authors.initials: AE
authors.lastname: Patanwala
authors.forename: John P
authors.initials: JP
authors.lastname: Winkler
authors.forename: Albert B
authors.initials: AB
authors.lastname: Fiorello
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Lee
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Olson
authors.forename: Donna M
authors.initials: DM
authors.lastname: Wolk
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology*; D017848:Blood-Borne Pathogens; D042241:Early Diagnosis; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents