顔面神経・外転神経麻痺を呈した悪性外耳道炎の1例

A Case of Malignant External Otitis with Cranial Nerve Involvement

I．はじめに

　悪性外耳道炎は，高齢の糖尿病を有する患者に発症する壊死性外耳道炎である^1）。本疾患は緑膿菌感染により生じ，難治性で頑固な耳痛が持続する。外耳道の炎症は骨破壊を伴い周囲組織に広がり，頭蓋底に浸潤して脳神経障害や髄膜炎などの重篤な病態を呈することがある。

　今回われわれは，慢性腎不全による血液透析患者において顔面神経麻痺，外転神経麻痺を生じた悪性外耳道炎の1例を経験したので，文献的考察を加えて報告する。

A 58-year-old male visited our hospital with a complaint of left ear pain. The patient had diabetes for 20 years,and had been receiving hemodialysis due to chronic renal failure. On the examination,an external otitis was observed in the left ear,and Pseudomonas aeruginosa was detected in otorrhea. The external otitis was improved within 10 days,but the ear pain persisted. Three months later the patient suddenly developed left facial nerve palsy. CT of temporal bone showed bone destruction in mastoid air cells and inflammatory change involving the facial nerve canal. Conservative therapy was seemingly successful in controlling the inflammation and gradual improvement of the facial nerve palsy. Eight months later,double vision due to left abducent nerve paralysis occurred. MRI showed inflammation extending to the apex of petrous part and cavernous sinus. Additional therapy was performed but the abducent nerve paralysis showed no change. The patient died of MRSA pneumonia,22 months after the onset of the malignant external otitis.