Autoimmune inner ear disorders

Incidence of autoimmune inner ear disease (AIED) is difficult to determine: probably it is a rare disease, accounting for less than 1% of all cases of hearing impairment or dizziness. Nevertheless, the diagnosis of AIED might be overlooked because of the lack of specific diagnostic tests. The hallmark of this clinically diagnosed condition is the presence of a rapidly progressive, often fluctuating, bilateral SNHL over a period of weeks to months. The progression of hearing loss is too rapid to be diagnostic for presbycusis and too slow to conclude a diagnosis of sudden SNHL. Vestibular symptoms, such as generalized imbalance, ataxia, positional vertigo and episodic vertigo may be present in almost 50% of patients. Occasionally only one ear is affected initially, but bilateral hearing loss occurs in most patients, with symmetric or asymmetric audiometric thresholds. Almost 25%-50% of patients have also tinnitus and aural fullness, which can fluctuate. Systemic autoimmune diseases coexist in 15%-30% of patients.