Postmortem findings in a patient with cerebral amyloid angiopathy actively treated with corticosteroid

We examined histopathological changes in cerebrovascular amyloid deposition in a patient with cerebral amyloid angiopathy receiving corticosteroid therapy. A 69-year-old female developed subacute onset cognitive decline, and magnetic resonance image (MRI) showed subarachnoid hemorrhage with leptomeningeal enhancement. She entered in an apathetic state due to communicating hydrocephalus and a ventricle-peritoneal (V-P) shunt operation was performed. Brain biopsy disclosed multiple cortical microhemorrhages and severe Congophilic angiopathy with positive Aβ-immunoreactivity in most vessels. Inflammatory mononuclear cells surrounded a few severe amyloid-laden leptomeningeal vessels. She received high-dose corticosteroid, which was slowly tapered. She gradually recovered but finally died 1.5 years later with no recurrence of CAA-related hemorrhages. Postmortem examination of the brain showed multiple old microhemorrhages in the cortex and extensive degeneration of cerebral white matter. The cortical and leptomeningeal vascular walls showed a few Congophilic amyloid deposits, but small deposits with Aβ-immunoreactivity were frequently seen. There was no infiltration of inflammatory cells in either leptomeninges or vascular walls. Electron microscopy revealed sparse aggregation of amyloid fibrils in significant numbers of vascular walls. Biochemical analysis disclosed that Aβ1-40-immunoreactive amyloid protein fractions obtained from the patient's leptomeninges were very small in amount. Comparing the previous biopsy findings with those at autopsy, the total disappearance of the inflammatory cell infiltration and diminishing of the cerebrovascular amyloid deposits were noted.