アルコール性肝炎患者に発生した進行性多発性白質脳症の1例

A Case of Progressive Multifocal Leukoencephalopathy with Alcoholic Liver Dysfunction

Ⅰ．はじめに

　進行性多発性白質脳症（progressive multifocal leukoencephalopathy：PML）は，免疫力の低下した患者においてJCウイルス（JCV）の日和見感染によって起きる中枢神経系疾患であり，そのウイルスがoligodendrocyteに感染増殖するために白質病変が主体となる脱髄性疾患である^4,6,10)．PML発症の基礎疾患としてはAIDS（acquired immunodeficiency syndrome）や臓器移植後の免疫抑制剤使用患者などに発生することが多い^4,6,10)．今回われわれは，human immunodeficiency virus（HIV）陰性で免疫抑制剤などを使用していないアルコール性肝炎患者にPMLの発生を経験したため，若干の文献的考察を含め報告する．

　Progressive multifocal leukoencephalopathy (PML) is caused by opportunistic infection by JC virus and presents with progressive demyelinating lesions in the central nervous system. A 59-year-old man with a history of alcoholic liver dysfunction presented with progressive weakness of his left leg over a period of one month. MRI showed multiple white matter lesions that were of low intensity on the T1 image and high intensity on the T2 image,heterogeneously high intensity on the diffusion image,and were not enhanced with contrast media. The patient underwent open biopsy of the right parietal lesion. The histological findings were the demyelination and the enlargement of nuclei of oligodendrocytes. Electron microscopic examination showed numerous viral particles in the nuclei of the oligodendrocytes. Infection by JC virus in the central nervous system was diagnosed with the polymerase chain reaction (PCR) products sampled from the cerebrospinal fluid. The incidence of PML has significantly increased in immunosuppressive patients,such as AIDS (acquired immunodeficiency syndrome). We presented the first case of PML in an immune-compromised state with alcoholic liver dysfunction.