Allergic and immunologic aspects of Meniere's disease.

Meniere's disease, although idiopathic by definition, has been ascribed to a variety of causes, which more recently include autoimmune factors. Interest in the role of allergy in Meniere's disease has also increased. Studies from this institution and elsewhere provide evidence that allergy and immunologic factors play a role in Meniere's disease in at least some patients. The symptoms of Meniere's disease are thought to be produced by a sudden influx of fluid into the endolymphatic sac, producing a rupture of Reissner's membrane in the cochlea. The endolymphatic sac is capable of trapping antigen and generating its own immune response. It has a highly vascular subepithelial space containing numerous fenestrated blood vessels that are peripheral and "leaky." At least three mechanisms by which allergy may play a role in the production of fluid in the endolymphatic sac are described: the endolymphatic sac itself might be a "target organ" of mediator released from systemic inhalant or food reactions; deposition of circulating immune complex may produce inflammation and interfere with the sac's filtering capability; and a predisposing viral infection in childhood that produces a mild impairment of endolymphatic sac function may interact with allergies in adulthood and cause the endolymphatic sac to decompensate, resulting in endolymphatic hydrops. The endolymphatic sac is the seat of immune reactivity in the inner ear. Repeated inflammatory reactions can produce sac dysfunction and eventual production of Meniere's disease.