title: Predictive value of white blood cell count and C-reactive protein in children with appendicitis.
abstract: OBJECTIVE
  Few studies have addressed the predictive value of white blood cells (WBCs) and C-reactive protein (CRP) at different cutoff values in appendicitis. Our purpose was to determine the cutoff values for WBC and CRP at different periods during clinical evolution of appendicitis and to establish their use for the diagnosis of appendicitis and differentiation of simple from perforated appendicitis.
  
  
  METHODS
  We studied 198 patients operated on for appendicitis, which were further divided into 4 subgroups according to the time from the onset of symptoms to diagnosis. Receiver operating characteristic curves were constructed for CRP and WBC; the best cutoff points were used to calculate the sensitivity and specificity to discriminate patients with and without appendicitis and patients with simple and perforated appendicitis.
  
  
  RESULTS
  White blood cell and CRP individually and together had a high sensitivity to differentiate patients with and without appendicitis. The specificity of WBC and CRP taken individually and together to differentiate patients with simple and perforated appendicitis was high, but the sensitivity was low.
  
  
  CONCLUSIONS
  White blood cell and CRP could be used to support the clinical diagnosis of appendicitis, and, depending on the time from the onset of symptoms to diagnosis, to differentiate patients with and without appendicitis and discriminate simple from perforated appendicitis.
authors.affiliation: Department of Surgery and Emergency Unit, Hospital de Ovalle, Ovalle IV Region, Chile. beltran_01@yahoo.com
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Beltrán
authors.forename: Jorge
authors.initials: J
authors.lastname: Almonacid
authors.forename: Alfonso
authors.initials: A
authors.lastname: Vicencio
authors.forename: Jorge
authors.initials: J
authors.lastname: Gutiérrez
authors.forename: Karina S
authors.initials: KS
authors.lastname: Cruces
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Cumsille
mesh_terms: D000293:Adolescent; D001064:Appendicitis / Q000097:blood* / Q000175:diagnosis* / Q000601:surgery; D002097:C-Reactive Protein / Q000378:metabolism*; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007223:Infant; D007416:Intestinal Perforation / Q000097:blood / Q000175:diagnosis; D007958:Leukocyte Count; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
chemical_list: D002097:C-Reactive Protein