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Keratinic amyloidosis of the external auditory canal
Koichiro Wasano1, Hideyuki Saito2, Sho Kanzaki2
1Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan; Department of Otolaryngology, Japanese Red Cross Shizuoka Hospital, Shizuoka, Japan.
Objective:
We present a rare case of keratinic amyloidosis of the external auditory canal. This is only the seventh case reported of localized cutaneous amyloidosis of the external auditory canal with no systemic symptoms.
Patient:
A 62-year-old man, who had complained of an itchy external auditory canal and left-side hearing loss, was referred to our hospital because of a bilateral external auditory canal mass.
Intervention:
Biopsy of the external auditory canal mass suggested a diagnosis of amyloidosis. However, total systemic examination failed to identify any disease due to systemic amyloidosis. This led us to diagnose him with localized cutaneous amyloidosis of the external auditory canal.
Main Outcome Measure:
We follow up periodically with systemic examination and local observation.
Results:
Thirty months after the initial diagnosis, he remains in follow-up and has not shown any significant aggravation of the disease.
Conclusion:
In previous cases, the chief complaints were itching sensations and pain in the external auditory canal as well as a sense of discomfort when wearing a hearing aid. This suggests that chronic stimulation and inflammation of the skin lining the external auditory canal induced amyloidosis.
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