Immune-mediated inner ear disorders.

Immune-mediated inner ear disease is characterized by sensorineural hearing loss which is most often rapidly progressive and bilateral, may be accompanied by vestibular symptoms, and for which no cause can otherwise be identified. The problem may occur alone or in combination with other systemic autoimmune disorders. Recognition of this entity is important as a substantial number of such patients experience improvement in hearing following treatment with corticosteroids with or without other immunosuppressive agents. Immune response to inner ear antigens can be helpful in establishing the diagnosis. The lymphocyte transformation assay has been used in identifying such responses but is limited by sensitivity and inhibited by immunosuppression. Western blot identification of serum antibodies to a 68-kD antigen of the inner ear appears to be a promising means of identifying patients with immune-mediated inner ear disease. The antibody is present in the majority of patients with clinical features consistent with the disorder; it correlates with disease activity and is predictive of response to treatment. Nevertheless, response to corticosteroid therapy remains the most convincing evidence of the disease.