What clinical feature is most suggestive of an abdominal aortic aneurysm?

A pulsatile abdominal mass is the clinical feature that is most suggestive of an abdominal aortic aneurysm (AAA). An AAA is characterized by localized dilation of the abdominal aorta, and as it enlarges, it becomes palpable as a mass in the abdomen. The pulsatile nature of the mass can be observed during examination, which is typically correlated with the heartbeat. This is a distinctive and critical sign that indicates the presence of the aneurysm and helps differentiate it from other abdominal conditions.

In patients with AAA, abdominal tenderness may be present if there is irritation of surrounding structures or if the aneurysm has ruptured; however, tenderness alone is not a specific indicator of an aneurysm. Acute flank pain can be associated with renal colic or other conditions affecting the kidneys or ureters rather than directly indicating an AAA. Abdominal distension may occur in various scenarios, including bowel obstruction or ascites, but it lacks the specific association with an AAA when compared to the pulsatile abdominal mass. Thus, identifying a pulsatile mass during a physical examination is instrumental in diagnosing an AAA and prompting further imaging and management.