An unusual dark pigmentation on the tympanic membrane

Abstract

Objective: To report an extremely rare case of dark pigmentation on the tympanic membrane due to alkaptonuria, and to discuss the probable association between this condition and hearing loss.Case report: A 58-year-old man with alkaptonuria was admitted with tinnitus and hearing loss in both ears. Physical examination showed bluish-black pigmentation on the helixes of both ears and both sclerae. Otoscopic examination revealed dark discolouration of both tympanic membranes. Audiological evaluation revealed mixed high frequency hearing loss in both ears. Tympanometric examination revealed type A tympanograms bilaterally, and absence of acoustic reflexes both ipsilaterally and contralaterally. Computed tomography of the temporal bones revealed no abnormality.Conclusion: Clinicians should consider alkaptonuria in the differential diagnosis of patients with abnormal tympanic membrane pigmentation and hearing loss.