Presentation
Acute onset severe abdominal pain.
Patient Data
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There is a paucity of bowel gas in the mid- and left abdomen. The outline of the left psoas muscle is not visible, indicating a positive psoas sign. No features of bowel obstruction.
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Large mixed density hematoma in the retroperitoneum on the left, extending into the left hemipelvis. Fusiform aneurysm of the infra-renal abdominal aorta with hyperdensity in the mural thrombus.
Interventricular septum sign present, usually indicative of anemia.
Case Discussion
The positive psoas sign on the left is a non-specific sign, but should raise the possibility of retroperitoneal pathology. The patient's age and clinical presentation were concerning for a possible aortic aneurysm rupture and an urgent non-contrast CT was subsequently obtained which confirmed a ruptured aortic aneurysm with a large left retroperitoneal hematoma. The imaging findings were confirmed at surgery. The patient had an uneventful post-operative recovery period.