両眼の急激な視力障害で発症した自己免疫性視神経症の1例

A case of autoimmune optic neuropathy initiated by acute bilateral visual loss

要約　目的：視力障害で発症した自己免疫性視神経症の症例の報告。症例と経過：45歳女性に両眼の視力障害が突発して受診した。Basedow病と特発性血小板減少性紫斑病の既往があり，13日前から咽頭痛と熱発があり服薬中であった。視力は左右眼とも指数弁で，対光反射が減弱していた。2日後に両眼とも視力0となった。両眼に軽い乳頭浮腫があり，磁気共鳴断層検査（MRI）で両眼の視神経炎が推定された。血液検査で抗核抗体，抗サイログロブリン抗体，抗甲状腺ペルオキシダーゼ抗体が高値であり，自己免疫性視神経症と診断した。ステロイドパルス療法を行い，6か月後に矯正視力は右0.1，左0.04に回復した。結論：自己免疫性が疑われる視神経症では，早期であればステロイドの大量全身投与が奏効することがある。

Abstract.　Purpose：To report a case of autoimmune optic neuropathy with acute onset of visual failure in both eyes. Case：A 45-year-old female developed acute visual impairment in both eyes. She had Graves disease and purpura with idiopathic platelet decrease. She had fever and pharyngeal pain since 13 days before. When seen the same day, her visual acuity was counting fingers in either eye. Light reaction was decreased in both eyes. Her visual acuity became no light perception two days later. Both eyes showed disc edema. Magnetic resonance imaging（MRI）findings were suggestive of optic neuritis. Hematological studies showed elevation of antinuclear antibody, antithyroglobulin antibody, and antiperoxidase antibody. These findings led to the diagnosis of autoimmune optic neuropathy. Pulsed corticosteroid treatment resulted in visual acuity of 0.1 right and 0.04 left 6 months later. Conclusion：Systemic corticosteroid in massive dosis may be effective for autoimmune optic neuropathy if initiated early enough.