Review of experimental and clinical studies of autoimmune sensorineural hearing loss

The purpose of this review was to analyze recent studies, both clinical and experimental, on diagnosis and treatment of autoimmune sensorineural hearing loss (ASNHL). Relevant studies were identified by searching Chinese Biomedical Literature Database and China Academic Journals Full-text Database for articles published nationally during the period of 1993-2013. The manuscripts were analyzed for the following aspects: selection of patients, sample size, presence of control group, experimental methods, study outcomes including audiological evaluation results, and efficacy of treatment. Forty-one manuscripts were identified including 12 reviews, 2 case reports, 20 experimental studies, and 7 clinical studies. The patient numbers in clinical studies ranged from 14 to 71 patients. Five clinical studies included control group of healthy individuals, while further two studies had no control group. Patients with ASNHL were treated with corticosteroids (prednisone or dexamethasone) in all seven clinical studies. However, statistical analyses of therapeutic efficacy were not carried out. Animal models were developed by immunization with allogeneic inner ear antigen, and some pathological changes were not specific to the disease. Experimental animals also had various degrees of changes in auditory brainstem response. Treatment guidelines need to be developed, while specific criteria of treatment efficacy need to be established. Further research is needed to demonstrate that experimental ASNHL resembles pathophysiologically the clinical situation.