title: Healthcare-associated bloodstream infections in critically ill patients: descriptive cross-sectional database study evaluating concordance with clinical site isolates.
abstract: BACKGROUND
  Healthcare-associated bloodstream infections are related to both increased antibiotic use and risk of adverse outcomes. An in-depth understanding of their epidemiology is essential to reduce occurrence and to improve outcomes by targeted prevention strategies. The objectives of the study were to determine the epidemiology, source and concordance of healthcare-associated bloodstream infections with clinical site isolates.
  
  
  METHODS
  We conducted a descriptive cross-sectional study in critically ill adults admitted to a tertiary semi-closed intensive care unit in England to determine the epidemiology, source and concordance of healthcare-associated bloodstream infections with clinical site isolates. All nosocomial positive blood cultures over a 4-year study period were identified. Pathogens detected and concordances with clinical site are reported as proportions.
  
  
  RESULTS
  Contaminant pathogens accounted for half of the isolates. The most common non-contaminant pathogens cultured were Pseudomonas spp. (8.0%), Enterococcus spp. (7.3%) and Escherichia coli (5.6%). Central venous catheter-linked bloodstream infections represent only 6.0% of the positive blood cultures. Excluding contaminants and central venous line infections, in only 39.5% of the bloodstream infections could a concordant clinical site source be identified, the respiratory and urinary tracts being the most common.
  
  
  CONCLUSIONS
  Clinical practice should focus on a) improving blood culture techniques to reduce detection of contaminant pathogens and b) ensuring paired clinical site cultures are performed alongside all blood cultures to better understand the epidemiology and potential implications of primary and secondary discordant health-care associated bloodstream infections.
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Culshaw
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Guy
authors.initials: G
authors.lastname: Glover
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Craig
authors.initials: C
authors.lastname: Whiteley
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Katie
authors.initials: K
authors.lastname: Rowland
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Duncan
authors.initials: D
authors.lastname: Wyncoll
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Jones
authors.affiliation: Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, 1st Floor, East Wing, St Thomas' Hospital, London, SE1 7EH, UK ; Division of Asthma, Allergy and Lung Biology, King's College London, London, SE1 9RT, UK.
authors.forename: Manu
authors.initials: M
authors.lastname: Shankar-Hari
keywords: Bacteremia; Intensive care units; Nosocomial infections