デング熱後に両眼視神経症を発症した1例

A case of bilateral optic neuropathy following infection by dengue fever

要約　目的：デング熱に罹患した後に視神経症が両眼に発症した症例の報告。症例：30歳女性が両眼の光視症で受診した。3か月前にタイで勤務中にデング熱の重症型であるデング出血熱に罹患した。その5日後から両眼の視力が低下し，人の顔が判別できなかった。所見：矯正視力は右0.6，左0.9であり，両眼の視神経乳頭の鼻側縁が不鮮明で，蛍光眼底造影で同部位に過蛍光があった。視野検査で両眼に中心暗点と盲点の拡大があった。ビタミンB₁₂の内服のみを行い，初診から1か月後に両眼とも視力が1.0に回復した。結論：本症例ではデング出血熱後に視神経症が両眼に発症し，自然寛解したと解釈される。

Abstract.　Purpose：To report a case who developed optic neuropathy in both eyes after acute infection by dengue fever. Case：A 30-year-old female presented with photopsy in both eyes. She had been infected by dengue hemorrhagic fever 3 months ago while staying in Thailand. She noticed severely impaired vision in both eyes 5 days later. Findings：Corrected visual acuity was 0.6 right and 0.9 left. Both eyes showed blurring of nasal margin of optic disc. Fluorescein angiography showed hyperfluorescence in the same area. Perimetry showed enlarged blind spot and central scotoma in both eyes. Visual acuity improved to 1.0 in both eyes after treatment with peroral cyanocobalamin for one month. Conclusion：The present case illustrates that acute infection may be followed by severe optic neuropathy in both eyes which may heal spontaneously after a few months.