COVID-19ワクチン接種後に両眼性樹氷状網膜血管炎を発症した1例

Bilateral frosted branch angiitis following COVID-19 vaccination

要約　目的：COVID-19ワクチン接種後にぶどう膜炎発症のリスクがあることが知られている。今回，COVID-19ワクチン接種後に樹氷状網膜血管炎（FBA）を発症した症例を経験したので報告する。

症例：49歳，女性。既往歴はなし。4回目のCOVID-19ワクチン接種翌日に飛蚊症，2日後より両眼の充血，霧視，眼痛を自覚し，近医眼科を受診したところ，両眼のぶどう膜炎との診断で，同日に順天堂大学医学部附属浦安病院に紹介となった。初診時矯正視力は左右ともに1.2，前眼部所見は毛様充血，前房内炎症性細胞2＋，虹彩後癒着を認めた。眼底所見は両眼とも4象限にわたり樹氷状の網膜血管の白鞘化と一部網膜出血を認め，フルオレセイン蛍光眼底造影検査では網膜血管および視神経乳頭からの蛍光漏出および網膜周辺部に血管閉塞による無灌流領域を認めた。FBAと診断しベタメタゾン点眼とプレドニゾロン内服を開始したところ，視力は一時右（0.7），左（0.3）まで低下したが，眼内炎症所見と樹氷状変化は改善を認め，最終的には両眼（1.2）まで改善した。

結論：FBAは稀なぶどう膜炎であるが，COVID-19ワクチン接種を契機に健常成人において発症する可能性がある。

Abstract　Purpose：The risk of developing uveitis after coronavirus disease 2019（COVID-19）vaccination is well known. We report a case of frosted branch angiitis（FBA）that developed after COVID-19 vaccination.

Case：The patient was a 49-year-old woman with no medical history. She experienced floaters in both eyes a day after receiving her fourth dose of the COVID-19 vaccine. Two days post-vaccination, she experienced redness, blurred vision, and pain in both eyes. She was referred to our hospital with a diagnosis of uveitis. Visual acuity was 25/20 in both eyes. Slit lamp examination revealed ciliary injection, 2＋ inflammatory cells in the anterior chamber, and posterior synechiae. Fundus examination showed frosted branch-like retinal vasculitis with sheathing of the arteries and veins in all four quadrants of both eyes and retinal hemorrhages. Fluorescein angiography showed vascular leakage and vascular occlusion in the retinal periphery. Treatment with betamethasone eye drops and oral prednisolone improved the intraocular inflammation and sheathing of retinal vessels；her vision, which had decreased during the treatment course, improved to 25/20 in both eyes.

Conclusion：FBA is a rare form of uveitis that can occur in healthy adults and is triggered by COVID-19 vaccination.