Abdominal Wall Abscess Associated with Perforated Jejunal Diverticulitis: Report of a Case

We report a case of abdominal wall abscess caused by diverticulitis of the jejunum penetrating through the abdominal wall. A 53-year-old Japanese woman visited a local hospital complaining of abdominal pain and a mass in the left lower abdomen. An abdominal computed tomography scan showed a tumor with isodensity in the left lower abdominal wall. Magnetic resonance imaging showed a mass in the abdominal wall with isointensity in the T1-intensified image and high intensity in the T2-intensified images. The mass was heterogeneous inside and protruded partially toward the intraperitoneal cavity. Ultrasound examination showed a heteroechoic mass extending into the intraperitoneal cavity. Laparotomy revealed a tumor in the abdominal wall with a fistulous tract extending to the jejunum. We resected the abdominal wall tumor with partial resection of the small intestine. The resected specimen contained a tumor with a fistulous tract passing through the abdominal wall. Histological examination revealed remarkable infiltration of neutrophils and a bacterial mass in the abdominal wall tumor, with a fistulous tract connected to the area adjacent to the mesenteric border of the jejunum. These findings suggested that diverticulitis of the jejunum had penetrated through the abdominal wall, leading to the formation of an abscess. We report this case to highlight the need for complete gastrointestinal evaluation with gastrointestinal barium studies and imaging analysis to examine extension of intra-abdominal lesions in patients with an unexplained abdominal wall abscess.