Ulcerative colitis is a chronic and recurrent inflammatory disease characterized by the inflammation of the colon mucous membrane and causing abdominal pain, diarrhea, and hematochezia. Colonoscopy is considered as the method of choice for the diagnosis of this disease. Furthermore, the severity of this condition in the relapse periods is determined based clinical and laboratory criteria. Regarding this, the present study aimed to investigate the relationship between faecal calprotectin level, a cytosolic protein of neutrophils and macrophages, and the severity of disease in patients with ulcerative colitis relapse.

This cross-sectional study was conducted on 65 patients (i.e., 35 males and 30 females) with ulcerative colitis relapse. The results of clinical, laboratory, and colonoscopy examinations were collected using a checklist. Data analysis was performed in MED Cal statistical software (version 8).

According to the results, the mean age of the participants was 36.31±14.19 years. Out of the 65 patients, 26 (40%), 21 (32.3%), and 18 (27.7%) subjects had mild, moderate, and severe types of the disease, respectively. White blood cell count and erythrocyte sedimentation rate showed a significant decrease by the enhancement of disease severity and hemoglobin level (P<0.001). Furthermore, the mean level of faecal calprotectin demonstrated a significant elevation with the increase of the disease severity. The calprotectin level of > 387 μg/g with the sensitivity and specificity of 76.9% and 92.3%, respectively, was considered as indicating moderate and severe involvements.

As the findings indicated, faecal calprotectin level can be used as a non-invasive and reliable method to evaluate the severity of ulcerative colitis relapse.