Evaluation of mucosal healing of ulcerative colitis with clinical remission by a fecal immunochemical test

Background: Although the definitions of endoscopic mucosal healing in ulcerative colitis (UC) have usually included both Mayo endoscopic score (MES) 0 and 1, we previously reported that UC patients with clinical remission with MES 1 had a significantly higher risk of clinical relapse than patients with MES 0. We also revealed that a quantitative fecal immunochemical test (FIT) was useful to evaluate endoscopic activity in UC (Am J Gastroenterol.2013;108:83-9). The aim of this study was to determine predictive values of a FIT to discriminate patients with MES 0 from those with MES 1in UC patients with clinical remission.Methods: A total of 329 colonocopy cases with a FIT result performed for 189 patients in remission were evaluated.Results: Significant correlation was observed between FIT results and MES (spearman rank correlation coefficient; 0.5976, p < 0.0001). A majority of the patients with MES 0 showed a negative FIT (< 100 ng/mL) result (93%), and the proportion of the patients with a negative FIT result decreased with the rise of the MES (MES 0: 93%, MES 1: 41%, MES 2: 19%, p < 0.0001). The sensitivity and specificity of the negative FIT for MES 0 in UC patients with clinical remission were 0.93 and 0.67, respectively. Conclusion: A FIT can efficiently discriminate patients with MES 0, who have better prognosis, in UC patients with clinical remission.