右動眼神経麻痺のみを呈した梅毒性髄膜炎の1例

A Case Report of Syphilitic Meningitis with Right Oculomotor Nerve Palsy

要旨　患者は右眼瞼下垂および複視を主訴とする63歳男性。右動眼神経不全麻痺を認めるが，その他，失調症状および歩行障害を認めなかった。髄液細胞数の増加，血清および髄液迅速血漿レアギン試験陽性およびterponema pallidum抗体の上昇を認め，梅毒性髄膜炎による右動眼神経麻痺と診断した。ペニシリンG大量療法2,400万単位/日にて，特に副作用の出現なく，髄液細胞数は正常化した。その後，ステロイドパルス療法（ソル・メドロール^(R)1g/日，3日間）を2クール施行し，右眼瞼下垂および複視は改善した。神経梅毒は，動眼神経麻痺の重要な鑑別疾患であることを再認識し，また長期経過例においてもステロイドパルス療法を施行すべきであると考えた。

A 63-year-old man presented with acute-onset right ptosis and diplopia. The patient reported having engaged in unspecified sexual activities during his third decade and was found to have positive syphilitic serological findings at the age of 56 years. No clinical symptoms were noted at this time. On admission, he showed only right oculomotor nerve palsy. The patient's intelligence, gait and sensory functions were normal. Laboratory analysis revealed positive syphilitic serological findings and examination of the cerebrospinal fluid（CSF）further revealed pleocytosis, a higher IgG index and positive syphilitic reactions. A computed tomographic scan and other imaging studies were diagnostically nonspecific. We made a diagnosis of right oculomotor nerve palsy due to syphilitic meningitis. We treated the syphilitic meningitis with intravenous injections of penicillin G（24 million units per day for 21 days）. Jarisch-Herxheimer reaction and other side effects were not apparent. We first made a thorough examination of the CSF to rule out diagnosis of meningitis, and pursued methylprednisolone pulse therapy（MPP, 1g/day for 3 days）to treat the oculomotor nerve palsy. The ptosis and diplopia showed signs of improvement following the second MPP therapy session. The present case suggests that neurosyphilis is an important differential diagnosis for presentations of unspecific oculomotor nerve palsy and that MPP therapy may prove an effective treatment for it, even where there has been the long clinical onset.