Guidelines for Colonic Diverticular Bleeding and Colonic Diverticulitis: Japan Gastroenterological Association

Colonic diverticular disease has been increasing in prevalence in Japan due to the rapidly aging population. Colonic diverticular bleeding can result in hemorrhagic shock requiring blood transfusion, and it carries a high risk of recurrence within 1 year. Colonic diverticulitis can cause abscess, fistula formation, and perforation of the colon that may require surgery, and it often recurs. As a result, patients with colonic diverticular disease are often bothered by required frequent examinations, re-hospitalization, and a consequent decrease in quality of life. However, the management of diverticular disease differs between Japan and Western countries. For example, computed tomography (CT) is readily accessible at Japanese hospitals, so urgent CT may be selected as the first diagnostic procedure for suspected diverticular disease. Endoscopic clipping or band ligation may be preferred as the first endoscopic procedure for diverticular bleeding. Administration of antibiotics and complete bowel rest may be considered as first-line therapy for colonic diverticulitis. In addition, diverticula occur mainly in the sigmoid colon in Western countries, whereas the right side or bilateral of the colon is more commonly involved in Japan. As such, diverticular disease in the right-side colon is more prevalent in Japan than in Western countries. Against this background, concern is growing about the management of colonic diverticular disease in Japan and there is currently no practice guideline available. To address this situation, the Japanese Gastroenterological Association decided to create a clinical guideline for colonic diverticular bleeding and colonic diverticulitis in collaboration with the Japanese Society of Gastroenterology, Japan Gastroenterological Endoscopy Society, and Japanese Society of Interventional Radiology. The steps taken to establish this guideline involved incorporating the concept of the GRADE system for rating clinical guidelines, developing clinical questions (CQs), accumulating evidence through a literature search and review, and developing the Statement and Explanation sections. This guideline includes 2CQs for colonic diverticulosis, 24 CQs for colonic diverticular bleeding, and 17 CQs for diverticulitis.