title: Accurate cut-offs for predicting endoscopic activity and mucosal healing in Crohn's disease with fecal calprotectin.
abstract: BACKGROUND
  Fecal biomarkers, especially fecal calprotectin, are useful for predicting endoscopic activity in Crohn's disease; however, the cut-off point remains unclear. The aim of this paper was to analyze whether faecal calprotectin and M2 pyruvate kinase are good tools for generating highly accurate scores for the prediction of the state of endoscopic activity and mucosal healing.
  
  
  METHODS
  The simple endoscopic score for Crohn's disease and the Crohn's disease activity index was calculated for 71 patients diagnosed with Crohn's. Fecal calprotectin and M2-PK were measured by the enzyme-linked immunosorbent assay test.
  
  
  RESULTS
  A fecal calprotectin cut-off concentration of ≥ 170 µg/g (sensitivity 77.6%, specificity 95.5% and likelihood ratio +17.06) predicts a high probability of endoscopic activity, and a fecal calprotectin cut-off of ≤ 71 µg/g (sensitivity 95.9%, specificity 52.3% and likelihood ratio -0.08) predicts a high probability of mucosal healing. Three clinical groups were identified according to the data obtained: endoscopic activity (calprotectin ≥ 170), mucosal healing (calprotectin ≤ 71) and uncertainty (71 > calprotectin < 170), with significant differences in endoscopic values (F = 26.407, p < 0.01). Clinical activity or remission modified the probabilities of presenting endoscopic activity (100% vs 89%) or mucosal healing (75% vs 87%) in the diagnostic scores generated. M2-PK was insufficiently accurate to determine scores.
  
  
  CONCLUSIONS
  The highly accurate scores for fecal calprotectin provide a useful tool for interpreting the probabilities of presenting endoscopic activity or mucosal healing, and are valuable in the specific clinical context.
authors.affiliation: Servicio de Aparato Digestivo, Hospital Juan Ramón Jiménez, España.
authors.forename: Juan María
authors.initials: JM
authors.lastname: Vázquez Morón
authors.affiliation: UGC Aparato Digestivo, Huelva University Hospital Complex - Hospital Juan Ramón Jiménez, Spain.
authors.forename: Héctor
authors.initials: H
authors.lastname: Pallarés Manrique
authors.affiliation: Evolutive, Educative, Social and Methodological Ps, University Jaume I of Castellón, Spain.
authors.forename: Francisco H
authors.initials: FH
authors.lastname: Machancoses
authors.affiliation: UGC Aparato Digestivo, Huelva University Hospital Complex - Hospital Juan Ramón Jiménez , Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ramos Lora
authors.affiliation: Environmental Biology and Public Health Department, University of Huelva, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Ruiz Frutos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D003424:Crohn Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000628:therapy; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011770:Pyruvate Kinase / Q000032:analysis; D012016:Reference Values; D055815:Young Adult
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex; D011770:Pyruvate Kinase