Sensorineural hearing loss in Vogt-Koyanagi-Harada syndrome.

BACKGROUND: Vogt-Koyanagi-Harada (VKH) syndrome is a systemic condition characterized by ocular inflammatory disease as well as skin, ear, and meningeal manifestations. Patients with VKH often report tinnitus and hearing loss, but these symptoms tend to be given secondary consideration because most undergo treatment with steroids to prevent blindness resulting from granulomatous uveitis, exudative retinal detachment, and optic nerve inflammation. METHODS/STUDY DESIGN: In the current retrospective review, 24 patients with this syndrome were screened for auditory system abnormalities. All patients denied history of noise exposure or ototoxic agent exposure. The age range of the patients was 13 to 42 years. RESULTS: Three patients reported tinnitus and two patients reported sudden hearing loss. One patient experienced vertigo and aural fullness. Eight of 24 patients had pure-tone thresholds greater than 25 dB hearing loss at two or more frequencies. Five of 24 of these patients experienced hearing loss outside of the 95% confidence interval for published age-matched control populations. There was sloping sensorineural hearing loss at 4 kHz and above in five of 24 patients. All eight patients with hearing loss experienced some degree of hearing loss at 4 kHz or above. Three patients had mild to moderate low-frequency sensorineural hearing loss. There were no tympanometric abnormalities suggestive of conductive involvement. Abnormal acoustic reflex decay was observed in one patient. CONCLUSIONS: We conclude that a significant number of patients with VKH experience sensorineural hearing loss and that every patient with VKH should undergo a review of systems for auditory abnormalities and referral for audiologic testing if symptomatic. It is possible that untreated patients may experience worse symptoms.

Knock-in mouse model for resistance to thyroid hormone (RTH): an RTH mutation in the thyroid hormone receptor beta gene disrupts cochlear morphogenesis.

Thyroid hormone and the beta isoform of its receptor, Trb, are essential for normal development of the mammalian auditory system. We have analyzed auditory system function and structure in a mouse strain with a targeted Thrb mutation, Thrb(PV), which leads to the loss of binding of thyroid hormone (T3) to the Trb protein. Heterozygosity for the orthologous human THRB(PV) mutation and other similar mutations in human THRB cause resistance to thyroid hormone (RTH), which is occasionally associated with mild sensorineural hearing impairment. Auditory brainstem response analysis of heterozygous Thrb(PV)/+ mice demonstrates that they develop normal hearing. In contrast, Thrb(PV)/Thrb(PV) mice have severe hearing impairment that is already present at 3 weeks of age. This hearing loss is associated with disruption of postnatal morphogenesis of the tectorial membrane and organ of Corti. Comparison with the previously described phenotype of a Thrb -/- knockout strain suggests that Thrb(PV) disrupts the function of other genes that are critical for development and/or maintenance of these structures.