Superior Mesenteric Artery Syndrome Mimicking Functional Vomiting in an Adolescent: A Case Report

Abstract

Superior mesenteric artery (SMA) syndrome, also known as Wilkie or Cast syndrome, is a rare cause of proximal small bowel obstruction resulting from compression of the third part of the duodenum between the SMA and aorta due to a narrowed aorto-mesenteric angle. It typically presents with postprandial abdominal pain, nausea, and vomiting, with diagnosis primarily confirmed through radiological imaging. A 14-year-old male presented with persistent vomiting for one week, along with a history of similar episodes over the preceding six years. Physical examination revealed mild dehydration, a scaphoid, soft, and non-tender abdomen. Imaging demonstrated a reduced SMA angle, decreased aorto-mesenteric distance, and duodenal compression, consistent with SMA syndrome. The patient was managed conservatively with aprepitant, leading to symptom resolution and an uncomplicated discharge. SMA syndrome remains a rare and often under-recognised condition; delayed diagnosis can lead to significant morbidity. Prompt recognition and appropriate management, whether conservative or surgical, generally result in favourable outcomes. Clinicians should maintain a high index of suspicion in patients with chronic, unexplained upper gastrointestinal symptoms to avoid diagnostic delay.