Acute gastric dilatation due to a superior mesenteric artery syndrome: an autopsy case

Background: Superior mesenteric artery (SMA) syndrome occurs when the third portion of duodenum becomes tightly compressed between the SMA and the abdominal aorta (AA). Several causes of the SMA syndrome have been postulated such as marked weight loss, external compression of the abdomen, anatomic variation, and surgical alterations of anatomy. This is an autopsy case of a subject with atypical duodenal obstruction related SMA syndrome. Case presentation: A 71-year-old woman died one and a half days after eating a large meal of roast meat and vegetables and experiencing subsequent nausea and abdominal pain. At autopsy, fatal acute gastric dilatation was confirmed. The posterior parietal peritoneum around the duodenum was scarred and pulled the root of the mesentery involving the SMA. The complex compressed and narrowed the third portion of the duodenum. The root of the mesentery was also thickened and had adhered to the surface of the duodenum, which may have been due to past peritonitis and disturbance of duodenal motility. Aggregation of an excessively large food mass obstructed the lumen of the duodenum. The cause of death was diagnosed as SMA syndrome with intra-duodenal aggregation of an excessively large mass of food in the narrowed duodenal lumen. Conclusion: This is an atypical fatal case of acute gastric dilatation, through an excessively large mass of food obstruction at the latent narrowed duodenum.