Role of autoimmunity in contralateral delayed endolymphatic hydrops.

Contralateral delayed endolymphatic hydrops is described as the development of fluctuating hearing loss and episodic vertigo in a normal ear years following sensorineural hearing loss in the opposite ear. This condition is a variant of delayed endolymphatic hydrops in which new symptoms of severe episodic vertigo develop years later in an ear that has lost most or all of its hearing. The possible etiologies of these two conditions are unknown and may be different. This report presents seven cases of the contralateral form of this disease and experimental evidence that suggests that these patients may be suffering from the initiation of an autoimmune event directed against the remaining inner ear. In Western blot analysis, their serum was reacted against cow cochlear inner ear antigen preparations, and six of the seven cases had serum antibodies directed against a 68 or a 35-36 kilodalton (kd) molecular weight antigen in contrast to three of 43 normal controls (p < .001 Fisher's exact test), the significance of which had previously been reported for autoimmune inner ear disease.