Infected aortic aneurysm presenting as prevertebral abscess in magnetic resonance imaging: A case report

The differential diagnosis of mass-like lesions around the aorta includes saccular pseudoaneurysms and abscesses. A 69-year-old female was admitted with multiple abscesses and fluid collections in several muscles and joints. Methicillin susceptible Staphylococcus aureus was isolated from her blood and pus. Even though she was treated with repeated operations and appropriate antibiotics, her conditions worsened with persistent fever and newly developed abscesses at other sites. Serial enhanced computed tomography (CT) revealed a newly developed saccular abdominal aortic aneurysm in the retroaortic space at the celiac axis level. However, the infected aortic aneurysm mimicked a prevertebral abscess on enhanced spinal magnetic resonance imaging (MRI) due to its heterogeneous signal intensity caused by intraaneurysmal turbulent blood flow. We report to alert the pitfall in the diagnosis of saccular aortic aneurysm using spinal MRI and the importance of serial enhanced CT study in highly suspicious patients.