Anatomy Gone Wrong: A Rare Tale of Superior Mesenteric Artery Syndrome and Duodenal Obstruction

TL;DR

This paper presents a rare case of a 16-year-old with SMA syndrome causing duodenal obstruction, highlighting the need for timely diagnosis and surgical treatment when conservative methods fail.

Contribution

The paper contributes a detailed clinical case emphasizing the importance of recognizing SMA syndrome in adolescents with unexplained gastrointestinal symptoms.

Findings

The patient had a significantly reduced aorto-mesenteric angle (12°) and a hilum-to-SMA diameter ratio of 7.4, confirming SMA syndrome and nutcracker syndrome.

Conservative treatments failed, but laparoscopic gastrojejunostomy led to clinical improvement and resolution of symptoms.

The case underscores the need for cross-sectional imaging in diagnosing SMA syndrome and considering surgery when conservative management is ineffective.

Abstract

Aorto-mesenteric compression syndrome, also known as superior mesenteric artery (SMA) syndrome, is a rare but potentially serious condition caused by compression of the third portion of the duodenum between the abdominal aorta and the SMA. This anatomical narrowing leads to partial or complete duodenal obstruction and is often associated with significant weight loss and gastrointestinal symptoms. We present a case of a 16-year-old male who experienced four months of progressive postprandial vomiting, early satiety, and an 8 kg weight loss. On examination, he appeared mildly undernourished (BMI: 18) with epigastric tenderness. Laboratory tests revealed hypokalemia and metabolic acidosis. Abdominal contrast-enhanced CT demonstrated a significantly reduced aorto-mesenteric angle (12°) and compression of the left renal vein with a hilum-to-SMA diameter ratio of 7.4, consistent with the diagnosis of both SMA syndrome and nutcracker syndrome. Conservative treatment with nutritional support and positional therapy failed to alleviate symptoms. The patient subsequently underwent laparoscopic gastrojejunostomy, resulting in clinical improvement and resolution of vomiting. This case highlights the importance of considering SMA syndrome in adolescents presenting with chronic vomiting, weight loss, and nonspecific upper abdominal symptoms. Timely diagnosis through cross-sectional imaging is crucial, and surgical intervention should be pursued when conservative management proves ineffective.

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