A Case of Intraperitoneal Hemorrhage due to Arteriovenous Malformation in the Descending Colon

Abstract

A 72-year-old man presented to our hospital with left lower abdominal pain. Physical examination revealed mild rebound tenderness in the left lower abdomen. Contrast-enhanced computed tomography revealed a hematoma with extravasation of the contrast agent in the left lower mesentery ; hemorrhagic ascites and a diverticulum from the descending to the sigmoid colon were also seen. We made a diagnosis of acute peritonitis with peritoneal hemorrhage caused by penetration of the diverticulum of the descending colon into the mesentery. Emergency laparotomy revealed hemorrhagic ascites and a hematoma in the mesentery near the descending colon. After intraperitoneal lavage, we resected the descending colon and mesentery with a hematoma approximately 10 cm in length, and performed a descending colonostomy. The resected specimen demonstrated a hematoma and rupture of the mesentery without intraluminal hemorrhage. We modified our diagnosis to intraperitoneal hemorrhage due to an arteriovenous malformation (AVM) because histopathological examination revealed arteriovenous irregularity and a shunt in the submucosa. AVMs are one of the causes of gastrointestinal bleeding, but intraperitoneal hemorrhage caused by AVM of the colon is rare. Therefore, we present our case with the relevant literature.