Relationship between Fecal Calprotectin Level and Colonoscopy Findings in Ulcerative Colitis Patients Referred to the Gastroenterology Clinic, Gorgan, Iran (2020)

The diagnosis of inflammatory bowel disease (IBD) is performed by colonoscopy, sampling, and histopathology. Stool calprotectin is a test showing the presence of inflammation in the gastrointestinal tract. This study was done to determine the relationship between the calprotectin level in the feces and endoscopic findings in ulcerative colitis patients referred to the gastroenterology clinic in Gorgan, Iran.

This descriptive-analytical study was performed on 100 patients with ulcerative colitis referred to the gastroenterology clinic of Sayad Shirazi Hospital, Gorgan, north of Iran during 2020. The patients were asked to collect their stool samples one day before the procedure (just after taking the drug for bowel cleansing). Bowel cleansing was done by administering polyethylene glycol solution dissolved in water. The activity of ulcerative colitis was measured using the disease activity score. According to this criterion, a score greater than or equal to 5 is considered an active disease. Patients were classified into two groups: extensive or pan-colitis and left-sided colitis. Stool samples were evaluated for calprotectin in a single laboratory using a commercially available kit (Calprest- EuorociationspA. Trieste) at normal values of less than 50mg/g. The relationship between stool calprotectin with colonoscopic findings was evaluated.

The average duration of infection was 4±3.1 years in the time range of 1-14 years. The calprotectin level was less than 50 μg/g in 16 patients. Stool calprotectin less than 50 µg/g was seen in only 16 patients. There was no significant relationship between the level of calprotectin and the either age or gender of patients. Most patients (84%) had active disease based on colonoscopic findings. Left-sided involvement was seen in 60% of patients. Fecal calprotectin level was significantly higher in those with acute phase and those with severe disease (P<0.05). Additionally, the calprotectin level had no significant relationship with the location of bowel involvement, extension, and disease duration.

This study showed that the fecal calprotectin level in patients with ulcerative colitis had a significant relationship with the severity and activity of the disease in north of Iran.