広範な出血性病変を伴う可逆性後頭葉白質脳症症候群がみられ，脳アミロイドアンギオパチー関連炎症の合併が疑われた1例

抄録

A 70-year-old man presented with a generalized seizure that persisted for 30 minutes with decreased consciousness. Because he lived alone and had no relatives, his past medical, family, and medication history were unknown. On admission, T2-weighted and fluid-attenuated inversion-recovery magnetic resonance imaging revealed patchy high-intensity areas in the bilateral frontotemporal and parietal lobes. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient map revealed that the edema within these lesions was of vasogenic origin. Posterior reversible encephalopathy syndrome with onset seizure was diagnosed. The patient was maintained at normal blood pressure and levetiracetam treatment was initiated. His consciousness level improved temporarily but deteriorated again. T2*-weighted imaging revealed multiple macro- and micro-hemorrhages in the bilateral cortical and subcortical regions, consistent with cerebral amyloid angiopathy. Because a brain biopsy could not be performed, probable cerebral amyloid angiopathy-related inflammation was considered in accordance with Chung’s diagnostic criteria. The patient was started on steroids, with both clinical and radiological improvement. Posterior reversible encephalopathy syndrome involves numerous neurologic emergencies and is not always reversible. Earlystage investigation of the cause of posterior reversible encephalopathy syndrome, such as cerebral amyloid angiopathy-related inflammation, is important. Neurologists should be aware of this clinical association because early treatment can reduce the outcome severity.