経過中にBálint症候群を発症し，塩酸メフロキンとミルタザピンの併用療法により改善した進行性多巣性白質脳症の1例

A Patient with Progressive Multifocal Leukoencephalopathy Who Developed Bálint Syndrome Improved by Combination Therapy Using Mefloquine and Mirtazapine

症例は62歳男性で，悪性リンパ腫に対する臍帯血移植後に急激な視力低下をきたした。頭部MRIにて両側頭頂葉および後頭葉の皮質下白質〜深部白質に高信号域を認め，脳生検および脳脊髄液中JCウイルス（JCV）検査にて進行性多巣性白質脳症（PML）と診断した。経過中にBálint症候群を合併したが，塩酸メフロキンとミルタザピンの併用療法によりBálint症候群および頭部MRI所見は改善し，脳脊髄液中JCVは陰性化した。PMLではBálint症候群を合併し得ること，ならびに塩酸メフロキンとミルタザピン併用療法は有効であることを示した。

Abstract

We describe a 62-year-old man who developed subacute visual loss after cord blood stem cell transplantation for malignant lymphoma. Brain magnetic resonance imaging (MRI) showed bilateral hyperintense lesions in the occipital and parietal lobes. A diagnosis of progressive multifocal encephalopathy (PML) was established following brain biopsy and detection of JC virus (JCV) deoxyribonucleic acid (DNA) in the cerebrospinal fluid (CSF). He developed optic ataxia and visual inattention, and was then diagnosed as having Bálint syndrome. After he was treated with mefloquine and mirtazapine, his Bálint syndrome and, MRI findings improved and the copy number of JCV DNA in the CSF decreased. In summary, we demonstrate that patient with PML may develop Bálint syndrome and that combination therapy using mefloquine and mirtazapine may be an effective treatment.

(Received August 23, 2018; Accepted November 29, 2018; Published March 1, 2019)