Case of the Week
Section Editors: Matylda Machnowska1 and Anvita Pauranik2
1University of Toronto, Toronto, Ontario, Canada
2BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
Sign up here to receive an email alert when a new Case of the Week is posted.
October 25, 2010 (Supplemental Case)
Mycotic/Infectious Aneurysm
- Incidence varies from 1.2-5.4% of all intracranial aneurysms.
- Symptomatology is frequently nonspecific and includes fever, headache, seizures, and occasionally, focal neurologic signs and symptoms. Presence of such symptoms in a patient with endocarditis or in an immunocompromised patient with fungal infection should be worrisome for an underlying mycotic aneurysm.
- These lesions are characterized by their distal location and multiplicity. They mostly affect the distal segments of the middle cerebral artery (MCA).
- They arise as a result of infectious emboli invading the vessel wall by hematogenous route or from local spreading.
- Mortality is greater than 90% in untreated patients because catastrophic hemorrhage may occur.
- Key Diagnostic Features: Digital Angiography (DSA) is the gold standard for evaluation of these lesions. Magnetic resonance angiogram (MRA) or CT angiogram (CTA) can be utilized to initially evaluate these aneurysms. An intensely enhancing lesion contiguous with its parent vessel or a prominent flow-void especially in the distal cerebral vasculature in a patient with a relevant clinical history should raise the suspicion for an underlying mycotic aneurysm.
- Treatment includes appropriate antibiotic therapy and surgical excision.