Audiometric manifestations of Waardenburg's syndrome.

We studied 23 patients (from 11 families) who had Waardenburg's syndrome. Patients were evaluated by conventional audiometric methods and by distortion-product otoacoustic emissions to determine the penetrance and the degree and type of hearing loss. Twelve of the patients had the type I form of the syndrome and 11 had type II. Overall, we found hearing loss in 19 of the 23 patients (83%); hearing loss affected nine type I patients (75%) and 10 type II patients (91%). Five type I patients (42%) and eight type II patients (73%) had a hearing loss of > 100 dB. Bilateral symmetrical hearing loss was the most common type of loss, as it was seen in six of the type I patients (50%) and eight of the type II patients (73%). At lower frequencies, distortion-product otoacoustic emission amplitudes were found to be significantly above the noise floor in five of the 11 patients whose hearing thresholds were 60 dB HL or worse by click auditory brainstem response testing. These findings led us to conclude that it is necessary to use otoacoustic emissions in patients with Waardenburg's syndrome in order to provide optimum fitting of hearing aids, especially in children.