先行感染があり抗GQ1b抗体陽性であったフィッシャー症候群の3例

Three cases of Fisher syndrome with antecedent infection and positive anti-GQ1b antibody

要約　目的：フィッシャー症候群3例の報告。

症例：それぞれ32歳の男性，36歳の男性，43歳の女性で，全例が上気道感染に続き複視が発症していた。全例に腱反射の低下があり，抗CQ1b抗体が陽性で，フィッシャー症候群と診断した。1例には運動失調と異常感覚，1例には嚥下障害と構音障害があった。1例には免疫グロブリン療法，他の1例にはステロイドパルス療法，1例は無治療で軽快した。ステロイド療法を行った例は1年4か月後に再発し，免疫グロブリン療法で寛解した。

結論：フィッシャー症候群の3例すべてに上気道感染があり，複視が続発し，抗CQ1b抗体が陽性であった。突発する複視の症例では，フィッシャー症候群の可能性を考え，先行感染の有無についての問診と，抗CQ1b抗体の検索が重要である。

Abstract　Purpose：To report three cases of Fisher syndrome.

Cases：The present series comprised a 32-year-old male, 36-year-old male, and 43-year-old female. All the cases had a history of respiratory tract infection followed by diplopia. All the cases showed decreased tendon reflex and were positive for anti-CQ1b antibody, leading to the diagnosis of Fisher syndrome. One case showed, in addition, ataxia and another case showed signs of bulbar palsy. One case received immunoglobulin therapy and another case received corticosteroid pulse therapy. The third case received no specific therapy. All the 3 cases showed improvements. The patient who received corticosteroid pulse therapy showed relapse 16 months later and was successfully treated by immunoglobulin therapy.

Conclusion：All the 3 cases of Fisher syndrome showed infection of respiratory tract followed by diplopia. All the 3 cases were positive for anti-CQ1b antibody. Cases with diplopia of sudden onset may be manifestation of Fisher syndrome.