Autoimmune Inner Ear Disease at the Otology–Rheumatology Interface: Mechanisms, Diagnosis and Treatment

Autoimmune inner ear disease (AIED) encompasses immune-mediated sensorineural hearing loss occurring either in isolation or in association with systemic autoimmune, vasculitic or autoinflammatory disorders. Its diagnosis remains difficult because progressive or fluctuating hearing loss is not specific to immune-mediated cochlear injury, and no disease-specific biomarker has been validated. This review examines AIED from the combined perspectives of otology and rheumatology, focusing on systemic disease associations, pathogenic mechanisms, diagnostic limitations and therapeutic evidence. Experimental studies implicate blood–labyrinth barrier disruption, inflammatory cell recruitment, adaptive immune responses and microvascular injury, although direct confirmation of these mechanisms in primary human AIED remains limited. Clinically, serial audiometry, exclusion of alternative causes and targeted assessment for systemic inflammatory disease remain central to evaluation. Corticosteroids are commonly used as initial treatment, but therapeutic responsiveness does not establish the diagnosis. Evidence supporting conventional immunosuppressants and biologic agents remains insufficient for routine application in primary AIED. We distinguish findings obtained directly from patients with suspected AIED from evidence derived from related systemic disorders and experimental models, and identify the methodological priorities needed to improve diagnostic classification and treatment evaluation.