title: A new rapid quantitative test for fecal calprotectin predicts endoscopic activity in ulcerative colitis.
abstract: BACKGROUND
  Fecal calprotectin (FC) determined by the enzyme-linked immunosorbent assay (ELISA) test has been proposed as a promising biomarker of endoscopic activity in ulcerative colitis (UC). However, data on its accuracy in predicting endoscopic activity is scarce. Besides, FC determined by the quantitative-point-of-care test (FC-QPOCT) that provides rapid and individual results could optimize its use in clinical practice. The aims of our study were to evaluate the ability of FC to predict endoscopic activity according to the Mayo score in patients with UC when determined by FC-QPOCT and to compare it with the ELISA test (FC-ELISA).
  
  
  METHODS
  FC was determined simultaneously by FC-ELISA and FC-QPOCT in patients with UC undergoing colonoscopy. Clinical disease activity and endoscopy were assessed according to the Mayo score. Blood tests were taken to analyze serological biomarkers.
  
  
  RESULTS
  A total of 146 colonoscopies were performed on 123 patients with UC. FC-QPOCT correlated more closely with the Mayo endoscopic subscore (Spearman's correlation coefficient rank r = 0.727, P < 0.001) than clinical activity (r = 0.636, P < 0.001), platelets (r = 0.381, P < 0.001), leucocytes (r = 0.300, P < 0.001), and C-reactive protein (r = 0.291, P = 0.002). The prediction of "endoscopic remission" (Mayo endoscopic subscore ≤1) with FC-QPOCT (280 µg/g) and FC-ELISA (250 µg/g) presented an area under the curve of 0.906 and 0.924, respectively. The interclass correlation index between both tests was 0.904 (95% confidence interval, 0.864-0.932; P < 0.001).
  
  
  CONCLUSIONS
  FC determined by QPOCT was an accurate surrogate marker of "endoscopic remission" in UC and presented a good correlation with the FC-ELISA test.
authors.affiliation: Department of Gastroenterology, Bellvitge University Hospital, Barcelona, Spain.
authors.forename: Triana
authors.initials: T
authors.lastname: Lobatón
authors.forename: Francisco
authors.initials: F
authors.lastname: Rodríguez-Moranta
authors.forename: Alicia
authors.initials: A
authors.lastname: Lopez
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez
authors.forename: Lorena
authors.initials: L
authors.lastname: Rodríguez-Alonso
authors.forename: Jordi
authors.initials: J
authors.lastname: Guardiola
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D002097:C-Reactive Protein / Q000378:metabolism; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000378:metabolism; D004724:Endoscopy; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000737:chemistry*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex; D002097:C-Reactive Protein