Intimal Sarcoma of the Descending Aorta Mimicking Aortitis.

We describe a 74-year-old male patient with an intimal sarcoma of the descending aorta mimicking aortitis. The patient presented with lower back pain, fever, and increased C-reactive protein, erythrocyte sedimentation rate, and immunoglobulin G4 (IgG4) serum levels, together with Staphylococcus epidermidis-positive blood cultures. These findings, together with evidence of a 49-mm pseudoaneurysm of the descending thoracic aorta, caused us to suspect aortitis. However, postoperative histology and immunohistochemistry demonstrated the presence of an intimal aortic sarcoma. At the 8-month follow-up, local recurrence of the neoplasm and lung metastases were noted.