Mycotic pseudoaneurysm of the aortic isthmus secondary to salmonella infection causing a diagnostic dilemma.

Mycotic pseudoaneurysms usually arise from an infectious arteritis or mycotic aneurysms secondary to weakening and destruction of the arterial wall resulting in a contained rupture. We report a case of a mycotic pseudoaneurysm affecting the aortic isthmus of the thoracic aorta which is an extremely rare infection. To our knowledge no case report of mycotic pseudoaneurysm of the aortic isthmus secondary to salmonella infection has thus far been described. The specific case we present is also unique in that it posed a diagnostic imaging dilemma where the initial imaging revealed a periaortic mass which could not be accurately characterized and only on subsequent imaging reveal itself to be a thrombosed mycotic pseudoaneurysm. We hope that our case report highlights to the medical community the high degree of suspicion one should have regarding pseudoaneurysms when dealing with a complex mass intimately related to a vascular structure.