Cortical petechial hemorrhage, subarachnoid hemorrhage and corticosteroid-responsive leukoencephalopathy in a patient with cerebral amyloid angiopathy.

We describe a 69-year-old woman who developed subacute onset cognitive decline after hitting the left side of her head. Cerebral spinal fluid showed yellowish discoloration with highly elevated protein content. FLAIR MRI revealed diffuse high signal intensity in all cortical sulci, and leptomeningeal enhancement in the left cerebral hemisphere was seen in the T1 image after contrast administration. She was treated with a corticosteroid. Consciousness disturbance was temporarily relieved but again worsened, resulting in an apathetic state due to communicating hydrocephalus. A shunt tube was placed in her right lateral ventricle. A brain biopsy disclosed multiple cortical microbleeds and heavy deposition of Abeta-immuoreactive amyloid on vascular walls. Inflammatory mononuclear cells surrounded a few leptomeningeal vessels. After the operation her condition further deteriorated and she fell into a coma. MRI showed diffuse swelling of the right cerebral white matter. She again received high-dose corticosteroid and gradually recovered during the following 2 months. On MRI the vast majority of abnormal signals in the right cerebral white matter disappeared. An initial manifestation of this patient was possibly caused by multiple microhemorrhages from fragile cortical and subarachnoid vessels with Abeta-amyloid deposition, which was triggered by head trauma. CAA-related inflammation possibly worsened this condition. Additionally, surgical intervention for communicating hydrocephalus might have induced cerebral amyloid angiopathy (CAA)-related leukoencephalopathy in her right cerebral hemisphere. These CAA-derived manifestations are unusual and high-dose corticosteroids seems to be useful for vascular events in CAA patients.