視神経乳頭の腫脹から猫ひっかき病の診断に至った2例

Two cases of cat scratch disease with optic disc edema as the initial manifestation

要約　目的：視神経乳頭の浮腫で初発し，Bartonella henselae抗体が陽性で，猫ひっかき病と診断した2症例の報告。

症例：2症例とも男性で，年齢は27歳と52歳である。いずれも片眼性で，羞明または見えにくさが主訴であった。両患者ともネコの飼育歴はなかった。

所見と経過：いずれも片眼のみに病的所見があり，患眼の矯正視力はそれぞれ1.2と0.04であった。1例には乳頭浮腫と網膜静脈炎が初診時にあり，他の1例には乳頭浮腫と漿液性網膜剝離があった。両症例とも黄斑部に脂質沈着が生じた。両症例とも血清学的にB. henselae抗体が陽性で，猫ひっかき病と診断した。1例にはプレドニゾロン内服，他の1例にはステロイドパルス療法と抗菌薬投与を行った。両症例とも寛解し，それぞれ1.2と0.8の最終視力を得ている。

結論：ネコの飼育歴または濃厚接触がなくても，乳頭浮腫，網膜静脈炎，黄斑部の脂質沈着などがあれば，猫ひっかき病の可能性がある。

Abstract　Purpose：To report two cases who showed unilateral optic disc edema and who were positive for antibody to Bartonella henselae, leading to the diagnosis of cat scratch disease.

Cases：Both were males and were aged 27 and 52 years respectively. Both were unilaterally affected, and complained of photophobia or haziness in the involved eye. They had no relationship with domestic or wild cat.

Findings and Clinical Course：One eye only was affected in both cases. Corrected visual acuity in the affected eye was 1.2 and 0.04 respectively. One case showed optic disc edema with retinal periphlebitis. The other case showed optic disc edema and serous retinal detachment. Both cases showed lipid deposit in the macular area later. Both cases were positive for antibody to B. henselae, and were diagnosed with cat scratch disease. One case was treated by peroral prednisoslone. The other case received pulsed steroid therapy and systemic antifungal medication. The ocular lesion subsided in both cases, with 1.2 and 0.08 respectively as the final visual acuity.

Conclusion：These two cases illustrate that cat scratch disease may manifest as optic disc edema, retinal phlebitis, or lipid deposits in the macula even with no previous contact with domestic or cat.