ACUTE SUPERIOR MESENTERIC ARTERY SYNDROME

Clinical History

The patient was admitted with repeated bilious vomiting and severe abdominal pain after a regular diet with an irritable bowel.

Imaging Findings

The patient reported similar episode in the past and had lost 6 Kg in weight for 3 months. Physical examination revealed a dehydrated patient with tachycardia. Examination of the abdomen was unremarkable. Haematological and biochemical investigations were all within normal limits. A barium examination had been performed. This revealed a markedly dilated stomach and duodenum, with an abrupt cut off at the level of the third part of duodenum (fig 1). Computed tomography (CT) scan schowed a compression of the duodenum between the aorta and SMA (fig 2) and the aortomesenteric angle was lower. A diagnosis of superior mesenteric artery syndrome was made. Patient was treated by laparoscopic duodenojejunostomy

Discussion

The superior mesenteric artery syndrome is a rare form of intestinal obstruction (1). This syndrome is caused by an obstruction of the third part of the duodenum between the superior mesenteric artery anteriorly and the mid abdominal aorta posteriorly (2). The exact aetiology is not known, the syndrome has been associated with sudden weight loss, spinal surgery, rarely abdominal aortic aneurysm and pancreatitis. It usually affects young females 10 to 39 years (1). The symptomatology is commonly chronic, with weight loss, post-prandial epigastric pain due to a compression, bloating after meals, and vomiting (1,2). An acute presentation is uncommon (1). Barium meal examination may show constant dilatation of the proximal duodenum with a delay in the passage of contrast distally. The presence of a vertical linear extrinsic pressure defect in the third part of the duodenum is characteristic and disappears when the patient is placed in a prone position. These findings may be absent in the chronic form, their absence does not exclude the disease. If negative, the examination should be repeated, preferably during an acute attak. CT scan demonstrates compression of the duodenum (1). Treatment can be conservative or surgical. Non surgical treatments are recommended as an initial therapy of SMA syndrome. Conservative treatment entails decompression of the stomach intraveinous fluids and management of electrolytes. The patient can be advised to lie prone after meals to facilitate emptying of the stomach and duodenum and also, prescribed pro-kinetic agents. Surgery may be offered if symptoms are recurrent. Most surgeons agree that the most successful procedure for management of SMA syndrome is a duodenojejunostomy (1,2).  

Differential Diagnosis List

Final Diagnosis

superior mesenteric artery syndrome

URL:	https://www.eurorad.org/case/4740
DOI:	10.1594/EURORAD/CASE.4740
ISSN:	1563-4086