title: Recurrent bacteraemia: A 10-year regional population-based study of clinical and microbiological risk factors.
abstract: BACKGROUND
  A population-based nested case-control study was conducted in order to characterize patient factors and microbial species associated with recurrent bacteraemia.
  
  
  METHODS
  All patients with bacteraemia in a Danish region during 1996-2006 were investigated. Recurrence was defined based on pathogen identity, site of infection and time frame, and not restricted to homologous pathogens.
  
  
  RESULTS
  We identified 8672 patients with first-time bacteraemia, of whom 1003 (12%) had a recurrence within 1 year. The proportion of mono-microbial bacteraemia was similar for first (86%) and recurrent episodes (84%). An unknown focus was common in both episodes (22.7 and 29.1%, respectively). Independent predictors of a recurrence (incidence rate ratio, 95% confidence interval) included health care-associated (2.4; 1.9-3.0) and nosocomial bacteraemia (2.1; 1.8-2.6), poly-microbial Gram-positive bacteraemia (2.7; 1.6-4.6), and fungaemia (2.2; 1.4-3.5), a Charlson co-morbidity index score of 1-2 (1.7; 1.4-2.1), inappropriate empirical antimicrobial chemotherapy (1.3; 1.1-1.5), a gastro-intestinal tract focus (2.3; 1.7-3.0), a liver/biliary tract focus (2.7; 2.0-3.6), an iv-catheter focus (2.0; 1.4-2.8), endocarditis (2.7; 1.6-4.3), and an unknown focus (1.9; 1.5-2.3).
  
  
  CONCLUSIONS
  This study showed recurrent bacteraemia to be common and the following risk factors were identified: a health care-associated or nosocomial origin, poly-microbial or fungal aetiology, a focus within the abdomen, endocardium, iv-catheter-related or unknown, a Charlson co-morbidity index score of >1 and inappropriate empirical antimicrobial chemotherapy.
authors.affiliation: National Center for Antimicrobials and Infection Control, Statens Serum Institut, Copenhagen S, Denmark. uje@ssi.dk
authors.forename: Ulrich Stab
authors.initials: US
authors.lastname: Jensen
authors.forename: Jenny Dahl
authors.initials: JD
authors.lastname: Knudsen
authors.forename: Christian
authors.initials: C
authors.lastname: Ostergaard
authors.forename: Kim Oren
authors.initials: KO
authors.lastname: Gradel
authors.forename: Niels
authors.initials: N
authors.lastname: Frimodt-Møller
authors.forename: Henrik Carl
authors.initials: HC
authors.lastname: Schønheyder
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000453:epidemiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003428:Cross Infection / Q000453:epidemiology; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents