Cortical petechial hemorrhage, leukoencephalopathy, and subacute dementia associated with seizures due to cerebral amyloid angiopathy.

Although cerebral amyloid angiopathy is a well-known cause of cerebral lobar hemorrhage, subacute dementia, seizures, and acute encephalopathy without lobar hemorrhage are infrequently recognized as manifestations of this disease. In this report, we describe a case of cerebral amyloid angiopathy in a 74-year-old woman who had subacute progressive dementia and a superimposed rapid acute neurologic deterioration associated with seizures and the presence of cerebral edema on computed tomographic scans and leukoencephalopathy and cortical petechial hemorrhages on magnetic resonance imaging. A diagnosis of cerebral amyloid angiopathy in conjunction with small cortical infarcts and petechial hemorrhages was confirmed by antemortem biopsy. This clinical and radiologic picture is being increasingly recognized as characteristic of cerebral amyloid angiopathy.