Preserved otoacoustic emissions in postparotitis profound unilateral hearing loss: a case report.

We report a case of a profound unilateral sensorineural hearing loss following epidemic parotitis, with good response of otoacoustic emissions. The patient was a 12-year-old girl who had developed a unilateral hearing impairment 2 weeks after the onset of mumps. Pure tone audiometry confirmed a profound left sensorineural hearing loss. The affected ear showed an absence of auditory brain stem responses, whereas transient evoked otoacoustic emissions and distortion product otoacoustic emissions were preserved. Epidemic parotitis virus is likely responsible for an impairment of inner hair cells, primary afferent fibers or their synapses, or a combination of these areas, and it does not seem to have a specific tropism for cochlear outer hair cells. Further follow-up will be necessary to differentiate the present case from auditory neuropathy.