title: Immature granulocytes predict microbial infection and its adverse sequelae in the intensive care unit.
abstract: BACKGROUND
  We evaluated the predictive value of immature granulocyte (IG) percentage in comparison with white blood cell counts (WBC) and C-reactive protein (CRP), for infection, its invasiveness, and severity in critically ill patients.
  
  
  METHODS
  In 46 consecutive patients, blood samples were collected at the day (0) of a clinical suspicion of microbial infection and at days 1 and 3 thereafter. We defined infections, bloodstream infection, and septic shock within 7 days after enrollment.
  
  
  RESULTS
  Of the 46 patients, 31 patients had infection, 15 patients developed bloodstream infection, and 13 patients septic shock. C-reactive protein and IG percentage increased with increasing invasiveness and severity of infection, from day 0 onwards. Receiver operating characteristic analysis to predict infection showed an area under the curve of 0.66 (P=.10) for WBC vs 0.74 (P=.01) for CRP and 0.73 (P=.02) for IG percentage on day 0. Comparing WBC and CRP to WBC and IG percentage results in comparable prediction of microbial infection. Comparing WBC and CRP with WBC, CRP, and IG percentage suggests an additional early value of IG percentage, when not elevated, in ruling out infection.
  
  
  CONCLUSIONS
  Immature granulocyte percentage is a useful marker, as CRP, to predict infection, its invasiveness, and severity, in critically ill patients. However, the IG percentage adds to WBC and CRP in the early exclusion of infection and can be obtained routinely without extra blood sampling or costs.
authors.affiliation: Department of Intensive Care Medicine, Erasmus Medical Center, Rotterdam, the Netherlands. Electronic address: p.vandergeest@erasmusmc.nl.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: van der Geest
authors.affiliation: Department of Intensive Care Medicine, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Mohseni
authors.affiliation: Department of Clinical Chemistry, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: Brouwer
authors.affiliation: Department of Intensive Care Medicine, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Ben
authors.initials: B
authors.lastname: van der Hoven
authors.affiliation: Department of Public Health, Erasmus MC, Rotterdam, the Netherlands.
authors.forename: Ewout W
authors.initials: EW
authors.lastname: Steyerberg
authors.affiliation: Department of Intensive Care Medicine, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: A B Johan
authors.initials: AB
authors.lastname: Groeneveld
mesh_terms: D000368:Aged; D001424:Bacterial Infections / Q000097:blood* / Q000382:microbiology; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D016638:Critical Illness; D005260:Female; D006098:Granulocytes / Q000166:cytology*; D006801:Humans; D007362:Intensive Care Units; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012772:Shock, Septic / Q000097:blood* / Q000382:microbiology
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein
keywords: Critically ill; Diagnostic value; Immature granulocytes; Nosocomial infection