Fecal calprotectin concentration predicts outcome in inflammatory bowel disease after induction therapy with TNFα blocking agents.

Background: Fecal calprotectin (FC) concentration is a useful surrogate marker for mucosal healing (MH) during tumor necrosis factor alpha (TNFα)-blocking therapy for inflammatory bowel disease (IBD). Our aim was to evaluate whether a normal FC after induction therapy with TNFα antagonist predicts the outcome of IBD patients during maintenance therapy.
Methods: Sixty IBD patients (34 Crohn's disease [CD], 26 ulcerative colitis [UC]), treated with TNFα antagonists, either infliximab (n = 42) or adalimumab (n = 18), and having a documented FC level at baseline and after induction therapy were included. Disease activity was evaluated by partial Mayo score without endoscopy or Harvey-Bradshaw index at baseline, after induction, and at 12 months during maintenance therapy.
Results: After induction, FC was normalized (≤ 100 μg/g) in 31 patients (52%, median 42 μg/g, range 0-97), whereas the level remained elevated in 29 patients (48%, median 424 μg/g, range 116-5859). At ≈12 months, 26/31 (84%, 18 CD, 8 UC) of the patients with normal FC after induction were in clinical remission, whereas only 11/29 (38%, 9 CD, 2 UC) of those with an elevated (≥ 100 μg/g) postinduction FC were in clinical remission, P < 0.0001. After induction therapy with TNFα antagonists, a cutoff concentration of 139 μg/g for FC had a sensitivity of 72% and a specificity of 80% to predict a risk of clinically active disease after 1 year.
Conclusions: A normal FC after induction therapy with TNFα antagonists predicts sustained clinical remission in the majority of patients on scheduled therapy with active luminal disease.
(Copyright © 2012 Crohn's & Colitis Foundation of America, Inc.)