抗レトロウイルス薬多剤併用療法（HAART）中にlower body parkinsonismの増悪を認めたHIV脳症の1例

A Patient with HIV Encephalopathy Presenting with Parkinsonism during HAART Therapy

　要旨　症例はパーキンソニズムを主徴とするHIV脳症を呈した32歳男性。神経学的に寡動を主体とするパーキンソニズム，知能低下，前頭葉徴候を認め，画像所見では前頭葉を主座とする広範な白質病変が示唆された。Highly active antiretroviral therapy（HAART）導入後，中枢神経症状の改善を認めた。しかし，副作用のため抗レトロウイルス薬の組み合わせを変更するごとに症状は変動し，さらにHAART導入後1年経過した後，血漿HIV RNA量，末梢血CD4数とも良好な状態であったにもかかわらず，中枢神経症状は進行性に増悪した。HIV脳症はパーキンソニズムを主徴としうること，HAARTは薬剤の組み合わせによってHIV脳症に対する効果が異なること，HAARTによりCD4数が増加した状態を維持してもHIV脳症は増悪しうることを示した点で本例は貴重な症例と考えられた。

　We report the case of a 32-year-old man presenting symptoms of parkinsonism. Neurological examination revealed parkinsonism symptoms such as akinesia and postural instability, dementia and frontal lobe signs. He was diagnosed as having human immunodeficiency virus（HIV）encephalopathy. Brain MRI, ^99mTc ECD-SPECT and ¹H-MR spectroscopy demonstrated symmetrical cerebral white matter lesions, predominantly in the bilateral frontal lobes. Frontal lobe dysfunction could be responsible for his parkinsonism associated with HIV encephalopathy. His neurological symptoms improved transiently after the initiation of HAART but fluctuated when antiretroviral drugs were changed because of their side effects. Although HAART effectively decreased plasma HIV-RNA load and increased peripheral blood CD4 cell count, his parkinsonism and dementia eventually exacerbated. Our results suggest that a combination of antiretroviral drugs affects the therapeutic efficacy against HIV encephalopathy, and that CNS symptoms could be aggravated during HAART, even when plasma HIV-RNA load and CD4 cell count are maintained under favorable conditions.