Laharie D, Mesli S, El Hajbi F et al. Aliment Pharmacol Ther 2011;34:462–9.
Laharie et al. conducted a prospective study using fecal calprotectin (FC) to predict medium-term response in patients treated with infliximab. The study examined 65 adult patients with refractory luminal Crohn’s disease and measured C-reactive protein and FC at the start of infliximab treatment and post-induction (week 14), correlating this with continued clinical response at 1 year. The study did not demonstrate that FC values could predict response at 1 year even when different cut-off values for FC were used.
Fecal calprotectin (FC) is a neutrophil protein marker released in feces that is used to detect gastrointestinal inflammation [1]. It is a well-established test for diagnosing IBD, but well-designed studies validating its use in assessing response to treatment in patients with established Crohn’s disease are still needed. If FC assessment was validated as a good correlate of mucosal healing upon treatment in Crohn’s disease, it would potentially reduce the need for endoscopy for mucosal healing. Studies that have demonstrated mucosal healing after an induction course of infliximab by endoscopy have (in contrast with the findings of this study) shown that post-induction mucosal healing is a very good predictor of clinical response at 1 year [2]. Notably, only 58% of the 65 patients included in this study had active luminal Crohn’s disease at baseline. Of the 50 patients who responded to induction treatment, 23 had a clinical relapse at ≤1 year, making it difficult to make broad generalizations based on this specific patient group.