Which symptom indicates the presence of superior mesenteric artery syndrome?

The presence of superior mesenteric artery syndrome is characterized by symptoms related to gastrointestinal distress, particularly those that suggest obstruction or compression in the intestinal tract. Vomiting and abdominal distention are indicative of this condition, as they arise from the compression of the third part of the duodenum due to the abnormal positioning of the superior mesenteric artery. This positioning can lead to a functional blockage, making it difficult for food and digestive contents to pass through the intestines, resulting in these symptoms.

In the context of superior mesenteric artery syndrome, vomiting is a common response as the body attempts to reject contents that cannot progress through the digestive system. Abdominal distention occurs as retained contents build up behind the obstruction, causing the abdomen to swell and become painful. Thus, these two symptoms effectively demonstrate the type of digestive complications associated with the syndrome.