Superior Mesenteric Artery Syndrome

Superior mesenteric artery (SMA) syndrome — also called Wilkie's syndrome — is a rare cause of upper GI obstruction caused by extrinsic compression of the third part of the duodenum between the SMA anteriorly and the aorta posteriorly. The condition typically requires loss of the protective retroperitoneal fat pad, narrowing the aortomesenteric angle below 25° and the aortomesenteric distance below 8 mm.

Risk factors are unified by rapid weight loss: anorexia nervosa, malabsorptive states, post-bariatric surgery, severe burns, malignancy, and prolonged bed rest after spinal surgery. Symptoms include postprandial epigastric pain, early satiety, nausea, bilious vomiting, and progressive weight loss — often in a vicious cycle that exacerbates the underlying mechanical narrowing.

Diagnosis combines suggestive clinical history with cross-sectional imaging (CT angiography is the gold standard) showing a narrowed aortomesenteric angle. Initial management is conservative: nutritional rehabilitation (often via nasojejunal feeding distal to the obstruction or parenteral nutrition) and positional measures (left lateral decubitus, prone). Surgical bypass — duodenojejunostomy is the most common procedure — is reserved for patients who fail medical management or have advanced disease.