Sudden hearing loss in multiple sclerosis: case report.

This case illustrates the occurrence of a sudden hearing sensitivity loss that, in all likelihood, was the result of brainstem disorder resulting from multiple sclerosis (MS). Subject LD is a young woman who developed a sudden hearing loss while hospitalized for exacerbation of symptoms related to multiple sclerosis. By her own report, she had normal hearing in her left ear at the time of hospitalization. Four days after admission, she developed a hearing loss in her left ear, accompanied by roaring tinnitus and fullness. An audiologic evaluation revealed a substantial high-frequency sensitivity loss in the left ear. The combination of absent acoustic reflexes, depressed speech understanding, abnormal Bekesy audiometry, and an abnormal auditory brainstem response (ABR) was consistent with brainstem site of disorder. Over the next 2 weeks, hearing sensitivity recovered to within normal limits. This change in hearing sensitivity coincided with the recovery of acoustic reflexes, improvement in speech understanding, and partial recovery of the ABR.