Colonic diverticular bleeding due to a rupture of an ileocolic artery pseudoaneurysm secondary to colonic diverticulitis.

A 53-year-old woman with a history of recurrent right lower quadrant pain presented with slightly bloody stools in April 2023. She was initially diagnosed with acute diverticulitis using an abdominal computed tomography (CT) scan and was treated conservatively. On the second day, however, she reported significant hematochezia. A subsequent contrast-enhanced CT scan revealed an extravasation in the ascending colon, which was promptly managed with colonoscopy. Despite initial hemostasis, she experienced recurrent bleeding. Another contrast-enhanced CT scan revealed a pseudoaneurysm with ongoing extravasation in the same area. Angiography confirmed a pseudoaneurysm in a branch of the ileocolic artery, which was successfully treated by embolization. She was discharged after an 18 day hospital stay. This case highlights a pseudoaneurysm caused by diverticulitis.