Hyperammonemia complicating mesenteric vein thrombosis.

Hyperammonemic coma developed in a 69-year-old woman with prolonged symptoms of abdominal pain, dysphagia, and fever. At laparotomy for an acute condition within the abdomen, mesenteric vein thrombosis was found and partial intestinal resection was performed. Following surgery, the patient regained consciousness and blood ammonia levels became normal. Hyperammonemia and coma complicating mesenteric vein thrombosis have not yet been described. Venous shunts are suggested as being responsible for this rare complication.