title: Clinical and economic impact of contaminated blood cultures within the hospital setting.
abstract: Blood cultures have an important role in the diagnosis of serious infections, although contamination of blood cultures (i.e. false-positive blood cultures) is a common problem within the hospital setting. The objective of the present investigation was to determine the impact of the false-positive blood culture results on the following outcomes: length of stay, hotel costs, antimicrobial costs, and costs of laboratory and radiological investigation. A retrospective case-control study design was used in which 142 false-positive blood culture cases were matched with suitable controls (patients for whom cultures were reported as true negatives). The matching criteria included age, comorbidity score and month of admission to the hospital. The research covered a 13-month period (July 2007 to July 2008). The findings indicated that differences in means, between cases and controls, for the length of hospital stay and the total costs were 5.4 days [95% CI (confidence interval): 2.8-8.1 days; P<0.001] and £5,001.5 [$7,502.2; 95% CI: £3,283.9 ($4,925.8) to £6,719.1 ($10,078.6); P<0.001], respectively. Consequently, and considering that 254 false-positive blood cultures had occurred in the study site hospital over a one-year period, patients with false-positive blood cultures added 1372 extra hospital days and incurred detrimental additional hospital costs of £1,270,381 ($1,905,572) per year. The findings therefore demonstrate that false-positive blood cultures have a significant impact on increasing hospital length of stay, laboratory and pharmacy costs. These findings highlight the need to intervene to raise the standard of blood-culture-taking technique, thus improving both the quality of patient care and resource use.
authors.affiliation: Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, UK.
authors.forename: Y M
authors.initials: YM
authors.lastname: Alahmadi
authors.forename: M A
authors.initials: MA
authors.lastname: Aldeyab
authors.forename: J C
authors.initials: JC
authors.lastname: McElnay
authors.forename: M G
authors.initials: MG
authors.lastname: Scott
authors.forename: F W
authors.initials: FW
authors.lastname: Darwish Elhajji
authors.forename: F A
authors.initials: FA
authors.lastname: Magee
authors.forename: M
authors.initials: M
authors.lastname: Dowds
authors.forename: C
authors.initials: C
authors.lastname: Edwards
authors.forename: L
authors.initials: L
authors.lastname: Fullerton
authors.forename: A
authors.initials: A
authors.lastname: Tate
authors.forename: M P
authors.initials: MP
authors.lastname: Kearney
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000191:economics / Q000627:therapeutic use; D001431:Bacteriological Techniques / Q000191:economics; D001769:Blood / Q000382:microbiology*; D001800:Blood Specimen Collection / Q000379:methods; D016022:Case-Control Studies; D003362:Cost-Benefit Analysis; D003428:Cross Infection / Q000188:drug therapy / Q000191:economics*; D003470:Culture Media / Q000191:economics*; D004866:Equipment Contamination / Q000191:economics*; D005189:False Positive Reactions; D005260:Female; D017721:Hospital Costs; D006761:Hospitals; D006801:Humans; D007902:Length of Stay / Q000191:economics; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media