title: Accuracy and feasibility of point-of-care white blood cell count and C-reactive protein measurements at the pediatric emergency department.
abstract: BACKGROUND
  Several point-of-care (POC) tests are available for evaluation of febrile patients, but the data about their performance in acute care setting is sparse. We investigated the analytical accuracy and feasibility of POC tests for white blood cell (WBC) count and C-reactive protein (CRP) at the pediatric emergency department (ED).
  
  
  METHODS
  In the first part of the study, HemoCue WBC and Afinion AS100 CRP POC analyzers were compared with laboratory's routine WBC (Sysmex XE-2100) and CRP (Modular P) analyzers in the hospital central laboratory in 77 and 48 clinical blood samples, respectively. The POC tests were then adopted in use at the pediatric ED. In the second part of the study, we compared WBC and CRP levels measured by POC and routine methods during 171 ED patient visits by 168 febrile children and adolescents. Attending physicians performed POC tests in capillary fingerprick samples.
  
  
  RESULTS
  In parallel measurements in the laboratory both WBC and CRP POC analyzers showed good agreement with the reference methods. In febrile children at the emergency department (median age 2.4 years), physician performed POC determinations in capillary blood gave comparable results with those in venous blood analyzed in the laboratory. The mean difference between POC and reference test result was 1.1 E9/L (95% limits of agreement from -6.5 to 8.8 E9/L) for WBC and -1.2 mg/L (95% limits of agreement from -29.6 to 27.2 mg/L) for CRP.
  
  
  CONCLUSIONS
  POC tests are feasible and relatively accurate methods to assess CRP level and WBC count among febrile children at the ED.
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland; Department of Paediatrics and Adolescent Medicine, University of Turku, Turku, Finland.
authors.forename: Lauri
authors.initials: L
authors.lastname: Ivaska
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland; MediCity Research Laboratory, University of Turku, Turku, Finland.
authors.forename: Jussi
authors.initials: J
authors.lastname: Niemelä
authors.affiliation: Tykslab, Turku University Hospital, Turku, Finland.
authors.forename: Pia
authors.initials: P
authors.lastname: Leino
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland.
authors.forename: Jussi
authors.initials: J
authors.lastname: Mertsola
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland; Department of Paediatrics and Adolescent Medicine, University of Turku, Turku, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Peltola
mesh_terms: D000293:Adolescent; D016470:Bacteremia / Q000097:blood* / Q000175:diagnosis; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D004636:Emergency Service, Hospital; D005240:Feasibility Studies; D005260:Female; D005334:Fever / Q000097:blood* / Q000175:diagnosis; D006801:Humans; D007159:Immunologic Tests; D007223:Infant; D007755:Laboratories, Hospital; D007958:Leukocyte Count; D008297:Male; D019095:Point-of-Care Systems; D000067716:Point-of-Care Testing; D011379:Prognosis; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein