進行性の偽網膜色素変性を呈したwhite dot syndromeの1例

A case of pseudoretinitis pigmentosa with white dot syndrome as the initial manifestation

目的：多発消失性白点症候群（multiple evanescent white dot syndrome：以下，MEWDS）に続発した偽網膜色素変性症例の報告。症例と経過：生来健康な39歳女性が右眼をMEWDSと診断された。矯正視力は0.4であった。プレドニゾロンの全身投与を受けた。発症から2か月後に白斑は消失したが，夜盲が悪化し当科を受診した。矯正視力は0.3であり，広範な網膜色素上皮の萎縮があった。以後5年間硝子体内に炎症細胞が持続し，脈絡膜血管の萎縮が徐々に進行し視野とERGが悪化した。感染症を示唆する異常所見はなかった。全経過中，左眼に異常はなかった。結論：本症はMEWDSに続発した偽網膜色素変性の稀有例であると推定される。

Purpose：To report a case of white dot syndrome followed by pseudoretinitis pigmentosa. Case and Findings：A 39-year-old healthy woman had been diagnosed with multiple evanescent white dot syndrome（MEWDS）in her right eye. Her corrected visual acuity was reportedly 0.4. She was given peroral prednisolone. She was referred to us 2 months after onset. Corrected visual acuity was 0.3. Funduscopy showed extensive atrophy of retinal pigment epithelium in the right eye. No white dot was present. During the ensuing 5 years,the right eye showed persistent vitreous cells and progressive atrophy of choroidal vessels with deterioration of visual field and electroretinogram. She showed no laboratory findings suggestive of infection. Her left eye had remained normal throughout. Conclusion：The present case seems to be an extremely rare instance of pseudoretinitis pigmentosa secondary to MEWDS.