A case report of postoperative superior mesenteric vein thrombosis extending to the intrahepatic portal vein occurring as a complication of appendectomy

Abstract

A 39-year-old Japanese male presented with right lower abdominal pain and fever. Appendicitis was diagnosed, and antibiotics were immediately given intravenously. The patient's symptoms did not improve after 3 days, and the patient had an appendectomy. The appendix was located retrocecally, and there was no perforation or abscess formation. Postoperatively, the patient continued to have a low-grade fever. On follow up abdominal CT scan done on the 4^th postoperative day (POD), an abscess located adjacent to the ileocecal region was noted ; superior mesenteric vein (SMV) thrombosis was also found. The abscess resolved with intravenous antibiotic treatment, and the patient was discharged home on POD 15. However, on POD 19, the patient developed a fever over 38°C. The emergency abdominal CT scan showed that the thrombus, which had initially been located solely in the SMV, had extended into the intrahepatic portal vein. The thrombus resolved completely on oral antibiotics, aspirin, and warfarin treatment. SMV thrombosis is a rare complication of acute appendicitis. The current case is only the 5^th case reported in Japan to date.