Martine De Vos, Edouard J. Louis, Jürgen Jahnsen, Jo G.P. Vandervoort, Maja Noman, Olivier Dewit, Geert R. D'Haens, Denis Franchimont, Filip J. Baert, Roald A. Torp, Magne Henriksen, Philippe M.R. Potvin, Philippe P. Van Hootegem, Pieter M. Hindryckx, Tom G. Moreels, Arnaud Collard, Lars Normann Karlsen, Eirik Kittang, Guy Lambrecht, Tore Grimstad, Jonas Koch, Idar Lygren, Jean-Claude R.J. Coche, Fazia Mana, Andre Van Gossum, Jacques Belaiche, Mike R. Cool, Fernand Fontaine, Jean-Marc G. Maisin, Vinciane Muls, Bart Neuville, Dirk A. J. Staessen, Gert A. Van Assche, Thomas de Lange, Inger Camilla Solberg, Bert J.K. Vander Cruyssen, and Severine A.R.A. Vermeire
BACKGROUND: This study examined whether fecal calprotectin can be used in daily practice as a marker to monitor patients with ulcerative colitis (UC) receiving infliximab maintenance therapy.
METHODS: This prospective multicenter study enrolled adult patients with UC in clinical remission under infliximab maintenance therapy. Fecal calprotectin levels were measured every 4 weeks. Sigmoidoscopies were performed at inclusion and at study end. Relapse was defined as a clinical need for change in treatment or an endoscopic Mayo subscore of $2 at week 52. Sustained deep remission was defined as a partial Mayo score ,3 at all points and an endoscopic Mayo score 0 at week 52.
RESULTS: Full analysis was possible for 87 of 113 included patients with UC (77%). Of these patients, 30 (34.4%) were considered to be in sustained deep remission and 13 (14.9%) to have relapsed. Calprotectin levels in patients with sustained deep remission remained very low (median , 40 mg/kg at all time points). Patients who flared had significantly higher calprotectin levels (median . 300 mg/kg) already 3 months before the flare.
Further receiver operator curve analysis suggested that a calprotectin level .300 mg/kg had a reasonable sensitivity (58.3%) and specificity (93.3%) to model flare. Two consecutive calprotectin measurements of .300 mg/kg with 1-month interval were identified as the best predictor of flare (61.5% sensitivity and 100% specificity).
CONCLUSIONS: Fecal calprotectin can be used in daily practice to monitor patients with UC receiving infliximab maintenance therapy. Two consecutive measurements. 300 mg/kg is more specific than a single measurement for predicting relapse.