Superior mesenteric artery syndrome

Superior Mesenteric Artery Syndrome (SMA) is a rare but well recognized clinical entity characterized by compression of the third, or transverse, portion of the duodenum against the aorta by the superior mesenteric artery, resulting in chronic, intermittent, or acute, complete or partial duodenal obstruction. We describe a 14 -year-old African-American female with SMA syndrome who presented with a 6-month history of intermittent upper abdominal pain and postprandial vomiting. Past medical history was unremarkable except for dysmenorrhoea. Physical examination revealed a thin adolescent with a weight of 35 kg (10^th percentile), height of 150 cm (25^th percentile), and normal vital signs. The abdomen was slightly distended, with mild tenderness in the epigastric region and normal bowel sounds. Laboratory data including a complete blood count, ESR, and stool exam was normal. A plain roentgenogram of the abdomen revealed gastric distension. Abdominal and pelvic ultrasound were normal. An upper gastrointestinal contrast study showed duodenal dilatation of the first and second parts of the duodenum with characteristic vertical linear cutoff in the third part of the duodenum consistent with the diagnosis of SMA syndrome. Conservative treatment including adequate nutrition, gastrointestinal decompression, and proper positioning resulted in complete resolution of symptoms. Although SMA syndrome is uncommon, the feasibility of a clinical diagnosis and its therapeutic and prognostic implications justify a reminder to the physician. We recommend that an upper gastrointestinal barium study should always be performed in any patient with recurrent episodes of vomiting, particularly if the vomitus is bile stained and if vomiting is associated with evidence of undernutrition.