両側外耳道に生じた限局性皮膚アミロイドーシスの1例

A case of localized cutaneous amyloidosis of bilateral external auditory canals

はじめに

　アミロイドーシスは，全身の諸臓器の細胞外に線維状構造をもつ特異な蛋白質であるアミロイドが沈着し，機能障害を引き起こす疾患群で，全身諸臓器にアミロイドが沈着する全身性アミロイドーシスと，ある臓器に沈着が限局する限局性アミロイドーシスに大別される。耳鼻咽喉科領域でもアミロイドーシスの報告は散見されるが，部位別では喉頭が多く^1），外耳道に生じたアミロイドーシスの報告は少ない。今回われわれは，両外耳道限局性皮膚アミロイドーシスの1例を経験したので，文献的考察を加え報告する。

　A 66-year-old man with itchy ear was referred for further examination about his external auditory canal nodules. Several small nodules were seen in his bilateral external auditory canals. Tympanic membrane in both ears were clear and he had no hearing loss or ear fullness. The biopsy of the mass revealed amyloid deposit beneath the epithelium. Systemic examination showed no evidence of multiple myeloma, renal insufficiency, and amyloid deposit or symptoms of other organs. A final diagnosis of localized cutaneous amyloidosis of the external auditory canal was made.