title: Adjustment of antibiotic treatment according to the results of blood cultures leads to decreased antibiotic use and costs.
abstract: BACKGROUND
  To avoid the use of unnecessary broad-spectrum antibiotics, empirical therapy of bacteraemia should be adjusted according to the results of blood cultures.
  
  
  OBJECTIVE
  To investigate whether the results of blood cultures led to changes in antibiotic use and costs in a tertiary-care university hospital in Norway.
  
  
  METHODS
  Medical records from all patients with positive blood cultures in 2001 were analysed retrospectively. Factors predisposing to infections, results of blood cultures, antibiotic use and outcome were recorded. The influence of blood culture results on antibiotic treatment and costs were analysed.
  
  
  RESULTS
  The antibiotic use in 226 episodes of bacteraemia in 214 patients was analysed. According to the guidelines empirical antibiotic treatment should be adjusted in 166 episodes. Antibiotic use was adjusted in 146 (88%) of these 166 episodes, which led to a narrowing of therapy in 118 (80%) episodes. Compared with empirical therapy there was a 22% reduction in the number of antibiotics. Adjustment of therapy was more often performed in Gram-negative bacteraemia and polymicrobial cultures than in Gram-positive bacteraemia. In bacteraemia caused by ampicillin-resistant Escherichia coli, ampicillin was mostly replaced by ciprofloxacin. The cost for 7 days adjusted therapy in 146 episodes was euro19,800 (23%) less than for 7 days of empirical therapy.
  
  
  CONCLUSIONS
  Adjustment of antibiotic therapy according to the results of blood cultures led to a reduction in the number of antibiotics and a narrowing of antibiotic therapy. The costs for antibiotics decreased.
authors.affiliation: Department of Internal Medicine, Aker University Hospital, N-0514 Oslo, Norway. dag.berild@medisin.uio.no
authors.forename: Dag
authors.initials: D
authors.lastname: Berild
authors.forename: Atefeh
authors.initials: A
authors.lastname: Mohseni
authors.forename: Lien My
authors.initials: LM
authors.lastname: Diep
authors.forename: Mogens
authors.initials: M
authors.lastname: Jensenius
authors.forename: Signe Holta
authors.initials: SH
authors.lastname: Ringertz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000191:economics / Q000627:therapeutic use*; D016470:Bacteremia / Q000097:blood / Q000188:drug therapy* / Q000191:economics; D016527:Drug Costs; D004926:Escherichia coli / Q000187:drug effects; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D017408:Guidelines as Topic; D006785:Hospitals, University / Q000191:economics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents