Hearing loss as an initial symptom of the opsoclonus-myoclonus syndrome.

A patient in whom opsoclonus-myoclonus syndrome associated with a viral encephalitis developed was seen initially because of a hearing loss. Audiometric testing revealed the hearing loss to be bilateral and retrocochlear in type. Four days after the onset of hearing loss, the full opsoclonus-myoclonus syndrome developed. A review of the literature failed to disclose any other cases of the syndrome associated with hearing loss. On the basis of the available pathologic material in this disorder, the retrocochlear hearing loss was believed to have been caused by diffuse involvement of the brain-stem auditory pathways.