Development of a mycotic aneurysm within 4 days.

A 60-year-old man with chronic myelomonocytic leukemia was admitted for bacterial meningitis. Initial cranial CT and CT angiography (figure, A) were normal. Four days after admission, the patient became comatose. A subsequent cranial CT (figure, B) revealed a subarachnoid hemorrhage, and CT angiography (figure, C) showed a newly developed aneurysm of the basilar artery. We diagnosed a mycotic aneurysm due to acute meningitis. Apart from endocarditis, meningitis is a frequent cause of mycotic aneurysms.1 Cases of such rapid aneurysmal development are extremely rare, but should be thought of particularly in immunocompromised patients.2