The Value of Fecal Calprotectin As a Marker of Intestinal Inflammation in Patients with Ulcerative Colitis

BACKGROUND/AIMS To assess intestinal inflammation, simple, inexpensive and objective tools are desirable in inflammatory bowel disease. This study aimed to evaluate fecal calprotectin as a marker of active disease in ulcerative colitis. MATERIALS AND METHODS Sixty patients with a diagnosis of ulcerative colitis and 20 controls were recruited into the study. The disease activity of ulcerative colitis was determined by modified Truelove-Witts criteria and Rachmilewitz endoscopic index. The enzyme-linked immunosorbent assay was used to measure the concentrations of fecal calprotectin. C-reactive protein, erythrocyte sedimentation rate and hemogram were also measured, and inflammatory markers were compared with fecal calprotectin in determining disease activity. RESULTS Fecal calprotectin concentration in the patients with active ulcerative colitis (n=30) was significantly higher than that in the inactive ulcerative colitis group (n=30) and in the controls (n=20) (95% confidence interval: 232.5 (0.75-625) vs 11.7 (0.2-625), 7.5 (0.5-512) mg/L, p<0.001). There was no significant difference between the patients with inactive ulcerative colitis and controls (p>0.05). The calprotectin concentration was greater in the patients with a more severe clinical index, higher endoscopic activity (>4), elevated C-reactive protein, leukocytosis, and extensive colitis (p<0.05). The areas under the curve of the receiver operating characteristics were 0.817, 0.809, 0.532, and 0.507 for C-reactive protein, fecal calprotectin, leukocyte count, and erythrocyte sedimentation rate, respectively. There was a significant correlation between the fecal calprotectin concentration and the endoscopic activity in ulcerative colitis (r = 0.548, p<0.001). CONCLUSIONS Fecal calprotectin is a useful marker in the diagnosis of active disease and evaluation of clinical and endoscopic activity in ulcerative colitis.