Dramatic cognitive improvement with acetylcholinesterase inhibitor in cerebral amyloid angiopathyrelated inflammation

Context: Cerebral amyloid angiopathy (CAA) is characterized by progressive deposition of amyloid-ß fibrils in the walls of small arterioles and capillaries of the leptomeninges and cerebral cortex. A rare subtype of CAA is CAA-related inflammation (CAA-RI), which exhibits marked perivascular or transmural inflammatory infiltration in brain tissue. The major clinical features of CAA-RI are rapidly progressive dementia, behavioral changes, headache, seizures, or stroke-like signs. Conclusive diagnosis requires histopathological confirmation, but validated clinicoradiological criteria for the diagnosis of probable CAA-RI have good sensitivity (82%) and specificity (97%). Treatment with high dose corticosteroids with or without other immunosuppressive therapy is recommended. We report a case of probable CAA-RI that did not respond to corticosteroid therapy but had a surprising improvement with acetylcholinesterase inhibitor. Case report: A 77-year-old illiterate woman presented with a history of subacute onset of seizures and behavioral changes. Her medical history was positive for a hearing loss due to a toxic exposure in childhood, and a cured breast cancer. The neurological examination showed attention impairment, disorientation, and incoherent speech. CSF showed a mildly elevated protein count. Brain MRI met criteria for probable CAA-RI. She had a poor response with high doses of corticosteroids, but after a trial with Donepezil she showed important cognitive and functional improvement. Conclusion: This result attracts attention to the importance of the cholinergic pathway in the etiology and pathological mechanisms of CAA. Randomized Controlled Trials would be required to confirm our hypothesis and to find new therapeutic options for CAA.