Abstract
BACKGROUND: Colonoscopy can assess disease activity and severity of ulcerative colitis (UC) accurately, but it is invasive and costly. Role of noninvasive biomarkers of intestinal inflammation in evaluation of patients with UC is not well understood. In this study, we assessed fecal eosinophil cationic protein (FECP), fecal myeloperoxidase (FMPO), and fecal calprotectin (FC) as surrogate markers of disease activity and severity in patients with UC, and then evaluated effect of the combination of these markers. METHODS: Sixty-three UC patients and 59 cases of age-matched controls were investigated. All patients underwent clinical, endoscopic, and histological assessment for disease activity and severity. Fecal samples were analyzed for FECP, FC, and FMPO. RESULTS: All three fecal biomarkers were elevated in patients compared with controls (P = 0.000). Significant differences were found between inactive UC and controls (P = 0.000). Cases with severe UC had significantly higher FECP levels than those with mild UC (p < 0.05), but there were no significant differences in FC and FMPO levels among disease severity groups. All three biomarkers showed positive correlation with Ulcerative Colitis Activity Index (UCAI). The areas under the ROC curve of FECP, FC, and FMPO were 0.939, 0.783, and 0.785, respectively. Sensitivity and specificity of fecal biomarkers in assessing disease activity were FECP-88.46%, 89.47%; FC-80.77%, 68.42%; and FMPO-84.62%, 63.16%. CONCLUSIONS: All three fecal biomarkers could be used as surrogate markers for assessing disease activity of UC, and FECP provided superior discrimination than FMPO and FC. Moreover, FECP could distinguish between mild disease and severe disease group.