title: Fecal calprotectin as a predictor of abnormal colonic histology.
abstract: OBJECTIVE
  Gastroenterologists have been seeking reliable noninvasive indices of inflammatory and malignant bowel disease. This prospective study was to assess the value of fecal calprotectin in predicting abnormal histologic findings in patients undergoing colonoscopy.
  
  
  METHODS
  Stool specimens supplied before colonoscopy by 72 consecutive patients were measured for calprotectin levels, and the findings correlated with the colonoscopy results and other fecal and blood parameters. Receiver operating characteristics curve analysis was used to determine the predictive value of fecal calprotectin for abnormal colonic histology.
  
  
  RESULTS
  Patients with abnormal histologic findings had significantly higher calprotectin levels (218 +/- 125 mg percent) than patients with normal colonoscopy (77 +/- 100 mg percent). There was a highly significant correlation between calprotectin levels and erythrocyte sedimentation rate (r = 0.45, P = 0.008), positive fecal occult blood test (r = 0.57, P = 0.0001), and abnormal colonic histology (r = 0.54, P = 0.0001). Patients with active inflammatory bowel disease had higher calprotectin levels than the rest of the study patients (r = 0.3; P = 0.01). On multivariate analysis, calprotectin was a significant predictor of abnormal colonic histology (P = 0.005; odds ratio, 1.007; 95 percent confidence interval, 1.002-1.012). The area under the receiver operating characteristics curve was 0.79. A fecal calprotectin concentration of 150 microg/ml had a sensitivity of 75 percent, specificity of 84 percent, positive predictive value of 80 percent, and negative predictive value of 75 percent in predicting abnormal colonic histology.
  
  
  CONCLUSIONS
  Fecal calprotectin may serve as a simple, noninvasive surrogate marker of abnormal histologic findings in patients scheduled for colonoscopy.
authors.affiliation: Department of Gastroenterology, Shaare-Zedek Medical Center, Jerusalem, Israel. davariel@zahav.net.il
authors.forename: Ariella Bar-Gil
authors.initials: AB
authors.lastname: Shitrit
authors.forename: Dan
authors.initials: D
authors.lastname: Braverman
authors.forename: Halina
authors.initials: H
authors.lastname: Stankiewics
authors.forename: David
authors.initials: D
authors.lastname: Shitrit
authors.forename: Nir
authors.initials: N
authors.lastname: Peled
authors.forename: Kalman
authors.initials: K
authors.lastname: Paz
mesh_terms: D015415:Biomarkers / Q000032:analysis; D003108:Colonic Diseases / Q000378:metabolism* / Q000473:pathology; D003113:Colonoscopy; D016001:Confidence Intervals; D003937:Diagnosis, Differential; D005243:Feces / Q000737:chemistry*; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex