title: Fecal calprotectin and the clinical activity index are both useful to monitor medical treatment in patients with ulcerative colitis.
abstract: BACKGROUND
  Non-invasive monitoring of inflammatory bowel disease is an unmet clinical need as patients in clinical remission may have residual mucosal inflammation preceding clinical relapse.
  
  
  OBJECTIVE
  We aimed to assess the value of fecal calprotectin and standardized clinical activity scoring to monitor disease activity in ulcerative colitis under medical treatment.
  
  
  METHODS
  Forty-one patients with ulcerative colitis were included in a prospective observational study. Medical treatment was guided by clinical judgement of treating physicians. Fecal calprotectin and the clinical activity index (CAI) were measured blinded to treating physicians every 2 months until the end of follow-up. Twenty-six patients received colonoscopy for clinical reason.
  
  
  RESULTS
  As defined by the CAI, patients were in clinical remission (63.4 %), having mild (26.8 %) or moderate (11.2 %) disease activity. Of those in clinical remission (CAI ≤ 4), 86.4 % showed residual endoscopic activity (Mayo Score ≥1). Calprotectin levels were higher in endoscopically active disease (779.0 vs 331.5 μg/g, P = 0.034) and calprotectin testing identified more patients with endoscopic disease activity (86.4 %) than the CAI (45.5 %, P = 0.034). Medical treatment was escalated in 90.2 % during the study. Values of the CAI and calprotectin correlated with therapy escalation (OR 3.94 and 3.22, respectively). Only for calprotectin, changes between two measurements were related to intensified medical treatment (OR 1.39).
  
  
  CONCLUSIONS
  Fecal calprotectin was similarly useful to the CAI to monitor disease activity of ulcerative colitis during medical treatment but identified endoscopic disease activity far more reliably. Changes of calprotectin values between measurements might indicate clinical relapse earlier than the CAI.
authors.affiliation: Department of Gastroenterology, University Medical Clinic, Cantonal Hospital, Rheinstrasse 24, 4410, Liestal, Switzerland, emanuel.burri@ksbl.ch.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Burri
authors.forename: Christoph
authors.initials: C
authors.lastname: Beglinger
authors.forename: Stefanie
authors.initials: S
authors.lastname: von Felten
authors.forename: Frank Serge
authors.initials: FS
authors.lastname: Lehmann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000378:metabolism; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism; D003113:Colonoscopy; D005243:Feces / Q000737:chemistry*; D005260:Female; D005765:Gastrointestinal Agents / Q000627:therapeutic use*; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000378:metabolism*; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012074:Remission Induction; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; D015415:Biomarkers; D005765:Gastrointestinal Agents; D039841:Leukocyte L1 Antigen Complex