title: Predicting bloodstream infection via systemic inflammatory response syndrome or biochemistry.
abstract: BACKGROUND
  The yield of blood cultures is approximately 10%. This could be caused by inaccurate prediction of patients with bloodstream infection (BSI).
  
  
  OBJECTIVE
  To evaluate the usability of systemic inflammatory response syndrome (SIRS) or biochemical analyses as predictors for positive blood culture.
  
  
  METHODS
  We conducted a prospective cohort study at a Danish regional hospital from February 1 to April 30, 2010. All adult patients were included on the first time blood cultures were sampled during admission. Data were obtained from medical records, databases on microbiology, biochemistry, and antibiotic treatment. Data included time of admission, date and result of blood culture, results of biochemical analyses, and clinical measurements on the day of blood culture. Prediction of BSI was analyzed according to both individual parameters and parameters combined in different sepsis score groups. Associations were calculated using multiple logistic regression.
  
  
  RESULTS
  Patients with BSI (68 patients) were compared to patients without BSI (828 patients). Respiratory rate, body temperature, and C-reactive protein were strongest associated with BSI, with adjusted odds ratio (OR) 5.42, 95% confidence interval (CI) 1.13-25.9; OR 2.55, 95% CI 1.34-4.87; and OR 6.06, 95% CI 0.82-44.6, respectively. SIRS was associated with BSI, with crude OR 7.25, 95% CI 1.75-30.1. Neutrophil count and p-carbamide were not associated with BSI: adjusted OR 0.88, 95% CI 0.36-2.13 and OR 1.44, 95% CI 0.82-2.52, respectively. Only one of the sepsis score groups was associated with BSI: crude OR 2.13, 95% CI 1.08-4.19.
  
  
  CONCLUSIONS
  SIRS is an adequate predictor of BSI. By contrast, biochemical parameters were not useful as predictors of BSI.
authors.affiliation: Department of Clinical Microbiology, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: Rita Andersen
authors.initials: RA
authors.lastname: Leth
authors.forename: Bodil Elisabeth
authors.initials: BE
authors.lastname: Forman
authors.forename: Brian
authors.initials: B
authors.lastname: Kristensen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000175:diagnosis*; D001831:Body Temperature; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000378:metabolism; D011446:Prospective Studies; D056152:Respiratory Rate; D012680:Sensitivity and Specificity; D018746:Systemic Inflammatory Response Syndrome / Q000453:epidemiology*; D014508:Urea / Q000378:metabolism; D055815:Young Adult
chemical_list: D014508:Urea; D002097:C-Reactive Protein