Colouterine fistula caused by diverticulitis of the sigmoid colon

Colouterine fistula is an extremely rare condition because the uterus is a thick, muscular organ. Here, we present a case of a colouterine fistula secondary to colonic diverticulitis. An 81-year-old woman was referred to the emergency department with abdominal pain and vaginal discharge. Computed tomography showed a myometrial abscess cavity in the uterus adherent to the thick sigmoid wall. Upon contrast injection via the cervical os for fistulography, we observed spillage of the contrast into the sigmoid colon via the uterine fundus. Inflammatory adhesion of the distal sigmoid colon to the posterior wall of the uterus was found during surgery. The colon was dissected off the uterus. Resection of the sigmoid colon, primary anastomosis, and repair of the fistula tract of the uterus were performed. The postoperative course was uneventful. This case represents an unusual type of diverticulitis complication and illustrates diagnostic procedures and surgical management for a colouterine fistula.