急性散在性脳脊髄炎後に発症した小児視神経炎の1例

Optic neuritis in a child following acute disseminated encephalomyelitis

要約　目的：急性散在性脳脊髄炎後に視神経炎を呈した4歳児の症例報告。症例：4歳女児が左眼の視力低下で受診した。4か月前に急性散在性脳脊髄炎に罹患していた。所見と経過：視力は右1.0，左0.1であった。視神経乳頭の腫脹はなかった。MRIで左視神経に脱髄性病変を認めた。左視神経炎と診断し，ステロイドパルス療法を施行し，視力は左1.0に改善した。結論：急性散在性脳脊髄炎後に視神経炎を呈した症例であり，小児多発性硬化症への移行の可能性を考慮して長期の経過観察が必要と考えられた。

Abstract.　Purpose：To report a child who developed optic neuritis after disseminated encephalomyelitis. Case：A 4-year-old girl presented with impaired vision in the left eye. She had had acute disseminated encephalomyelitis 4 months before. Findings：Visual acuity was 1.0 right and 0.1 left. There was no swelling of optic disc in either eye. Magnetic resonance imaging（MRI）showed demyelinating lesions in the left optic nerve. She was diagnosed with optic neuritis. Treatment with pulsed corticosteroid was followed by improvement of left visual acuity to 1.0. Conclusion：In spite of favorable course of optic neuritis in this case, due precaution is needed as acute disseminated encephalomyelitis may be manifestation of pediatric multiple sclerosis.