title: Fecal calprotectin for the prediction of small-bowel Crohn's disease by capsule endoscopy: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Fecal calprotectin is a well-established marker of mucosal inflammation. Although the correlation of elevated calprotectin levels with colonic inflammation has been confirmed repeatedly, it is less established for the small bowel. The aim of the current study was to assess the diagnostic accuracy of calprotectin for the prediction of active small-bowel disease on capsule endoscopy by performing a diagnostic test meta-analysis.
  
  
  METHODS
  A comprehensive search was performed using PubMed/Embase. Studies addressing patients with suspected/established Crohn's disease (CD) evaluated with calprotectin and videocapsule were included. A diagnostic meta-analysis was carried out; pooled diagnostic sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for each cut-off.
  
  
  RESULTS
  Seven studies (463 patients) were entered into the final analysis. The DOR was significant for all the evaluated FC cut-offs (50 μg/g: sensitivity 0.83, specificity 0.53, DOR-5.64; 100 μg/g: sensitivity 0.68, specificity 0.71, DOR-5.01; 200 μg/g: sensitivity 0.42, specificity 0.94, DOR-13.64). On sensitivity analyses, when only studies addressing suspected Crohn's or retrospective studies were included, the results did not change significantly. For studies including patients with suspected CD only, the overall accuracy for FC cut-off 50 μg/g was further increased (sensitivity 0.89, specificity 0.55, DOR-10.3), with a negative predictive value of 91.8%.
  
  
  CONCLUSIONS
  Fecal calprotectin has a significant diagnostic accuracy for the detection of small-bowel CD. Our results suggest that in patients with suspected CD with calprotectin <50 μg/g, the likelihood of positive diagnosis is very low.
authors.affiliation: aDepartment of Gastroenterology, Sheba Medical Center, Tel Hashomer, and Sackler Medical School bDepartment of Medicine E, Rabin Medical Center, Petach Tikva and Sackler Medical School, Tel Aviv 52960, Israel cCentre for Liver & Digestive Disorders, The Royal Infirmary of Edinburgh, Edinburgh, Scotland, UK dDepartment of Gastroenterology, McGill University Health Center, Montreal, Québec, Canada.
authors.forename: Uri
authors.initials: U
authors.lastname: Kopylov
authors.forename: Diana E
authors.initials: DE
authors.lastname: Yung
authors.forename: Tal
authors.initials: T
authors.lastname: Engel
authors.forename: Tomer
authors.initials: T
authors.lastname: Avni
authors.forename: Robert
authors.initials: R
authors.lastname: Battat
authors.forename: Shomron
authors.initials: S
authors.lastname: Ben-Horin
authors.forename: John N
authors.initials: JN
authors.lastname: Plevris
authors.forename: Rami
authors.initials: R
authors.lastname: Eliakim
authors.forename: Anastasios
authors.initials: A
authors.lastname: Koulaouzidis
mesh_terms: D015415:Biomarkers / Q000032:analysis; D053704:Capsule Endoscopy; D003424:Crohn Disease / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D005243:Feces / Q000737:chemistry*; D006801:Humans; D007421:Intestine, Small / Q000737:chemistry* / Q000473:pathology*; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex