Superior Mesenteric Artery Syndrome in a 20-year-old Athletic Female with Abdominal Pain.

Correspondence To the Editor: A 20‑year‑old female college student and soccer player presented to the Emergency Department with acute onset of abdominal pain, nausea, and vomiting. On the morning of presentation, she woke up with sudden onset of epigastric pain that was constant and 10/10 in severity. The patient denied any obstipation, constipation, diarrhea, any recent trauma to the abdomen, or any potential inciting event. Of note, the patient did endorse previous episodes of postprandial epigastric pain, but it was never this severe. Her past medical and surgical history was unremarkable. Physical examination revealed an athletic female (height: 1.65 m, weight 45.0 kg, body mass index: 16.5 kg/m 2) who appeared uncomfortable on the stretcher. Her vitals were stable. Her abdomen was soft and non‑distended. There was moderate epigastric tenderness without guarding or rebound tenderness. A computed tomographic (CT) scan of the abdomen revealed moderate dilatation of the duodenum that measured up to 3.4 cm with an abrupt caliber change [Figure 1a and b] and decreased angle between the aorta and superior mesenteric artery (SMA) [Figure 1c]. The patient was diagnosed with SMA syndrome. SMA syndrome describes a constellation of symptoms due to duodenal compression by the SMA and abdominal aorta. In normal anatomy, the third portion of duodenum courses posteriorly to the SMA and anteriorly to the abdominal aorta at the level of the third lumbar vertebrae (L3). These three structures, along with the left renal vein, are surrounded by mesenteric fat pad and lymphatics. In patients with SMA syndrome, the aorto‑mesenteric angle is decreased to less than 25° (normal: 38–65°) and distance less than 8 mm (normal: 10–28 mm). SMA syndrome may be associated with entrapped left renal vein, or nutcracker, syndrome. Common etiologies of SMA syndrome include attenuation of mesenteric fat secondary to weight loss (most common) or surgical alteration of anatomy. Patient's presentation, physical exam, and laboratory findings are consistent with small bowel obstruction but are otherwise nonspecific. The patient's symptoms may include nausea, vomiting, and epigastric tenderness in either acute or chronic settings. The patient may endorse recent weight loss or abdominal surgery. Lying in positions that relieve tension between the SMA and aorta space such as the left decubitus or knee‑to‑chest may help alleviate symptoms. Differential diagnosis of SMA syndrome includes other causes of acute abdominal pain such as other causes of bowel obstruction, mesenteric ischemia, and gastroesophageal reflux disease (GERD). It may be …