A 29% prevalence rate of in-flight episodes consistent with alternobaric vertigo was obtained.

the age of 12. After that, the threshold moved to the stable. The audiogram indicated an asymmetric pattern and sensorineural hearing loss predominantly. A caloric test revealed a normal response on both sides. Corticosteroids were not effective in improving hearing loss. A diffuse goiter was noticed at the age of 15 years. The goiter slightly enlarged over the 12 years follow-up period.Conclusion: Although the His723Arg missense mutation is a change at unconserved position in the pendrin protein, it is a pathological mutation in our case because it was found in the homozygous state. It is possible that different mutations within the same gene lead to different phenotypes.