Surrogate markers of intestinal inflammation are predictive of relapse in patients with inflammatory bowel disease

Background&Aims: Prediction of relapse of inflammatory bowel disease has im portant implications for therapeutic stategies, We assessed whether measure ment of intestinal permeability and inflammation could predict relapse of i nflammatory bowel disease (IBD), Methods: Forty-three patients with Crohn's disease (CD) and 37 with ulcerative colitis (UC) in clinical remission pro vided a stool sample to be assayed for calprotectin (a neutrophil-specific marker), and patients with CD additionally underwent a small intestinal per meability test. Relapse was defined using clinical disease activity indices . Results: Twenty-five (58%) patients with CD and 19 (51%) with UC had a re lapse over the 12-month period. Median calprotectin levels in the relapse g roups (122 mg/L for CD, 123 mg/L for UC; normal <10 mg/L) differed signific antly (P < 0.0001) from those of the nonrelapse groups (41.5 mg/L for CD, 2 9.0 mg/L for UC), At 50 mg/L, the sensitivity and specificity of calprotect in for predicting relapse in all patients with IBD were 90% and 83%, respec tively. Permeability in the CD patients who relapsed (median, 0.075; normal <0.04) differed significantly (P = 0.004) from that in the nonrelapse grou p (median, 0,038), At the level of 0,05, the sensitivity and specificity of permeability in predicting relapse were 84% and 61%, respectively, Conclus ions: Fecal calprotectin predicts clinical relapse of disease activity in p atients with CD and UC, whereas small intestinal permeability is a useful p redictor of relapse in patients with small intestinal CD.