title: Fecal level of calprotectin identifies histologic inflammation in patients with ulcerative colitis in clinical and endoscopic remission.
abstract: OBJECTIVE
  Histologic recovery of patients with ulcerative colitis (UC) often is incomplete, even among those in clinical and endoscopic remission. Persistent active microscopic inflammation is associated with an increased risk of relapse and colorectal neoplasia. A high level of fecal calprotectin (FC) is a reliable marker of endoscopic lesions in patients with UC. We evaluated the accuracy of FC in identifying patients with UC in clinical and endoscopic remission who still have histologic features of inflammation.
  
  
  METHODS
  We performed a prospective observational study of 59 patients with UC in clinical and endoscopic remission undergoing colonoscopy. Several biopsy specimens were collected from each colonic segment. Endoscopic remission was defined as a Mayo endoscopic subscore with a grade of 0 or 1. Active histologic inflammation was defined by the presence of neutrophils infiltrating crypt epithelial cells. FC was determined by enzyme-linked immunosorbent assay analysis.
  
  
  RESULTS
  Eighteen patients (30.5%) showed evidence of active histologic inflammation. Patients with active histologic inflammation had a significantly higher median level of FC (278 μg/g; interquartile range, 136-696 μg/g) than those without active histologic inflammation (68 μg/g; interquartile range, 30-172 μg/g) (P = .002). In multivariate analysis, the FC and Mayo endoscopic subscore (0 or 1) were each independent predictors of histologic inflammation. The level of FC identified active histologic inflammation in patients in clinical and endoscopic remission, with an area under the receiver operator characteristic curve value of 0.754.
  
  
  CONCLUSIONS
  Histologic inflammation is common among patients with UC in clinical and endoscopic remission. Patients with histologic features of inflammation can be identified reliably based on their fecal level of calprotectin.
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain. Electronic address: jguardiola@bellvitgehospital.cat.
authors.forename: Jordi
authors.initials: J
authors.lastname: Guardiola
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Triana
authors.initials: T
authors.lastname: Lobatón
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Rodríguez-Alonso
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Ruiz-Cerulla
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Claudia
authors.initials: C
authors.lastname: Arajol
authors.affiliation: Department of Pathology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Carolina
authors.initials: C
authors.lastname: Loayza
authors.affiliation: Department of Pathology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Sanjuan
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez
authors.affiliation: Department of Gastroenterology, Hospital Universitari de Bellvitge-Institut d'Investigació Biomédica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Rodríguez-Moranta
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D001706:Biopsy; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000473:pathology*; D003113:Colonoscopy; D005243:Feces / Q000737:chemistry*; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex
keywords: Deep Remission; Histologic Remission; IBD; Mucosal Healing