Abstract
A 57-year-old man visited a hospital because of fever and right lower abdominal pain in September, 2006. One week later, he was referred to our surgery department with a suspicion of acute appendicitis. He had spontaneous right lower abdominal pain, tenderness and rebound tenderness. An egg sized elastic-hard tumor was palpable in the right lower quadrant of the abdomen. Laboratory tests showed elevated white blood cell count and C-reactive protein level. Abdominal CT scan disclosed a gas containing 5cm tumor shadow at the ileocecal region. Emergent surgery was performed with preoperative diagnosis of an abdominal abscess caused by the perforation of acute appendicitis or colon diverticulitis. Laparotomy revealed remarkable thickness and redness of terminal ileum, and a large sized mass with mesenteric abscess in the ileocecal region. Therefore, ileocecal resection and intraabdominal drainage was performed. On the resected specimen, an ileal diverticulum penetrating to the mesentery was found at the point 4cm proximal to the Bauhin's valve. Pathological examination demonstrated a mesenteric abscess cased by penetration of the terminal ileal diverticulum. The postoperative course was uneventful and the patient was discharged 20 days after the operation.
