[Superior mesenteric vein syndrome: a case of duodenal stenosis caused by atypical malposition of the superior mesenteric vein].

Cases in which mesenteric vessels lead to stenosis of the duodenum are very rare. Several cases have been reported of patients suffering from stenosis of the last third of the duodenum due to a malpositioning of the superior mesenteric artery or the left renal vein. We report a 78-year-old patient who was suffering from dyspepsia, pain in the upper abdominal region, nausea, and vomiting. The medical history revealed that the patient had undergone a subtotal gastrectomy according to Billroth II at the age of 19 because of similar complaints. In the last 20 years the patient had to be laparotomized several times for ileus of the small intestine. Now the patient presented abdominal complaints with nausea and pressure in the upper abdominal region. Assuming an efferent-loop syndrome and adhesions, the patient was laparotomized. We discovered malpositioning of the superior mesenteric vein, leading to stenosis of the superior part of the duodenum. In fact, 60 years ago surgeons performed a duodenojejunostomy, circumvening the stenosis of the duodenum. With a "delay of 60 years", we then performed a subtotal gastrectomy according to Billroth II. The postoperative course was uneventful; the patient had no complaints and increased in body weight. To our knowledge, this is the first time that a stenosis of the duodenum due to malpositioning of the superior mesenteric vein has been observed.