両眼に重篤な眼所見を呈し視力予後が不良であった猫ひっかき病の1例

A case of cat scratch disease with severe ocular findings and poor visual outcome in both eyes

要約　目的：猫ひっかき病は，一般的に予後良好な人畜共通感染症である。眼病変が合併した場合も，典型的には視力予後が良好であることが多い。今回，非典型的な臨床像を呈する猫ひっかき病の1例を経験したため報告する。

症例：患者は41歳，男性。飼い猫から咬傷を受け，その1か月後に発熱と悪寒が出現したが，リンパ節腫脹はなかった。同時期に右眼の視力低下，飛蚊症を自覚した。さらに約1か月後に両眼の著明な視力低下を自覚し，近医から鹿児島大学病院眼科（当科）へ紹介となった。矯正視力は右15cm指数弁，左0.06。両眼に視神経乳頭腫脹，漿液性網膜剝離，黄斑浮腫，硝子体出血を認めた。当科初診から1週間後に左眼に星芒状白斑が出現した。臨床所見から猫ひっかき病を疑い，アジスロマイシン内服，ステロイドパルス療法を行ったところ，両眼の視神経乳頭腫脹や漿液性網膜剝離は改善した。さらにプレドニゾロン，ドキシサイクリン内服を行ったが，視力の改善は限定的だった。その後，抗Bartonella henselae抗体陽性が確認され，猫ひっかき病による視神経網膜炎と診断した。

結論：猫ひっかき病では視神経網膜炎を呈することがある。非典型的で重篤な眼所見を合併する場合には鑑別に挙がりにくく視力予後が不良である可能性があり，十分な問診と早期の治療介入の検討が望ましい。

Abstract　Purpose：Cat scratch disease is a zoonosis with a generally good prognosis. Even when ocular symptom is present, the prognosis is typically favorable. We report a case of cat scratch disease with an atypical and severe ocular presentation and poor visual outcome.

Case：A 41-year-old man presented with fever and chills, without lymphadenopathy one month after being bitten by his cat. At the same time, he was aware of decreased vision and floaters in his right eye. One month later, he became aware of markedly decreased vision in both eyes and was referred to our department from a local practice.

Findings and Clinical Course：The corrected visual acuity was counting finger in the right eye and 0.06 in the left eye, and there was optic nerve papillary swelling, serous retinal detachment, macular edema, and vitreous hemorrhage in both eyes. One week after the first visit to our department, an exudative macular star was observed in the left eye. After oral azithromycin and steroid pulse therapy, the optic nerve papillary swelling and serous retinal detachment in both eyes were improved. Prednisolone and doxycycline were also administered, but the improvement in visual acuity was limited. Subsequently, it was confirmed that anti-Bartonella henselae antibody was positive in the patient, and then, the diagnosis of neuroretinitis due to cat scratch disease was confirmed.

Conclusion：Cat scratch disease can sometimes present as neuroretinitis. Atypical and severe ocular findings made the diagnosis difficult and may lead to a poor visual prognosis. It is important to take the disease into account when we examine severe case of neuroretinitis and to start the therapy as soon as possible.