Abstracts

Rationale: New-onset refractory focal-onset seizures in the elderly population can present as a wide range of etiologies. Cerebral amyloid angiopathy-related inflammation (CAA-RI), a subset of cerebral amyloid angiopathy (CAA), is a rare and under-recognized disease that presents with focal-onset seizures, headaches, and subacute cognitive decline. This condition is characterized by perivascular inflammatory infiltration and amyloid deposition into cerebral tissue. This case describes an elderly female who presented with refractory focal-onset seizures secondary to CAA-RI, and who demonstrated dramatic clinical and radiological improvement from this condition with immunosuppressive therapy. Methods: An 82 year old woman with a history of migraines with visual auras was in her usual state of health until 3 months prior to her presentation. She described recurrent episodes of left sided paresthesia, associated with twitching of the left eyelid, and progression to involve the left face and arm, without associated leg involvement or alteration in mental status. Lamotrigine 100 mg BID and Keppra 250 mg BID decreased both the severity and frequency of these episodes, but they continued to persist. She also suffered from a mild but progressive decline in cognitive abilities. An initial MR Brain imaging study showed no acute abnormalities, but a repeat MR 2 months later showed hyperintensities on T2 and FLAIR sequences in the regions of right central sulcus and right occipital lobe with corresponding contrast enhancement mainly in the overlying leptomeninges. Results: A brain biopsy was performed with special stains sent for beta-amyloid and tau protein. The biopsy showed prominent beta-amyloid positive deposits in the walls of blood vessels, which were also hyalinized and associated with perivascular histiocytes (CD68+) and scattered T-lymphocytes (CD3+). Scattered extracellular amyloid plaques were also highlighted with a beta-amyloid immunostain. These findings were consistent with the diagnosis of cerebral amyloid-angiopathy-related inflammation. She was subsequently started on dexamethasone 4 mg tid. Upon this being initiated, her focal seizures completely resolved. She remained on the same dexamethasone dosing for seven days. A subsequent MR brain study performed one week after initiating treatment showed significant decrease in the leptomeningeal enhancement. Conclusions: CAA-RI is a rare subset of CAA, defined by the deposition of amyloid protein within the leptomeningeal and cortical arteries causing vasculitis or perivasculitis, and manifests by headaches, cognitive decline, and focal-onset seizures. Brain biopsy is necessary to confirm the diagnosis, and immunosuppressive therapy with corticosteroids results in clinical and radiological improvement. Our case highlights the importance of considering the diagnosis of CAA-RI in elderly patients with new refractory focal-onset seizures.