The yield of systematic biopsies during a normal colonoscopy in patients with chronic diarrhea

Aims Chronic diarrhea is a common condition in gastroenterology, often requiring extensive investigations to determine its cause. Colonoscopy is the gold standard for the exploration and management of chronic diarrhea. The practice of performing systematic colonic biopsies on normal mucosa during colonoscopy is common, but its clinical utility remains debated. Our study aimed to evaluate the clinical interest of systematic colonic biopsies on normal mucosa in patients suffering from chronic diarrhea.

Methods It was a descriptive retrospective study conducted over 6 years from January 2019 to June 2024, including all patients who underwent colonoscopy for chronic diarrhea. Patients with macroscopically normal colonic mucosa were selected. Systematic colonic biopsies were standardly taken from the right colon, transverse colon, left colon, and rectum, and histopathological results were analyzed to detect microscopic pathologies.

Results 75 patients were included. The average age was 46.8 years (17 to 80). The M/F sex ratio was 0.44. Smoking was noted in 17 patients (22.7%) and medication intake in 11 patients (NSAIDs: n=4, PPIs: n=7). An associated autoimmune disease was found in 6.7% of cases (type I diabetes: n=2, hypothyroidism: n=3), and ankylosing spondylitis (AS) was noted in 3 patients. Colonoscopy was normal in all our patients and complete with ileocecal valve intubation in 88% of cases. Preparation was deemed good in 84% of patients. Abdominal pain and weight loss were described in 26.7% and 14.6% of cases, respectively. Blood tests revealed anemia in 16% of patients, biological inflammatory syndrome in 12% of patients, and malabsorption syndrome in 4% of cases. Ileocolic biopsies were normal in 84% of patients (n=63). Histological abnormalities were observed in 16% of cases, divided into microscopic colitis in 5 patients (4 cases of lymphocytic colitis and 1 case of eosinophilic colitis), infectious colitis in 3 patients, and foreign body colitis in 1 patient. Chronic inflammatory bowel disease was diagnosed in 3 patients.

Conclusions Our study shows that the practice of systematic colonic biopsies on macroscopically normal mucosa in patients suffering from chronic diarrhea has significant diagnostic value. The results obtained reinforce the idea and suggest that it is still relevant to perform biopsies due to the significant detection of microscopic pathologies that can influence treatment and prognosis.

Publication History

Article published online:
27 March 2025