Audiological Patterns in Patients with Autoimmune Hearing Loss

[Autoimmune hearing loss and a chance of its development in children: literature review and own observations]

Autoimmune sensorineural hearing loss (AiSNHL) is an uncommon auditory disorder characterized by rapidly progressive bilateral hearing loss and a positive clinical response to treatment with corticosteroids and cytostatics. The prevalence of the disease in the adult population is less than 1% among all cases of subacute and permanent sensorineural hearing loss (precise data are unknown), it is even rarer in children. AiSNHL can be primary (isolated, organ-specific) or secondary (manifestation of another systemic autoimmune disease). The pathogenesis of AiSNHL is based on the proliferation of autoaggressive T cells and the pathological production of autoantibodies to the protein structures of the inner ear, which leads to damage to various parts of the cochlea (possibly also to the retrocochlear parts of the auditory system), less frequently to the vestibular labyrinth. Pathologically, the disease is most often represented by cochlear vasculitis with degeneration of the vascular stria, damage to hair cells and spiral ganglion cells, and endolymphatic hydrops. In 50% of cases, the result of autoimmune inflammation may be fibrosis and/or ossification of the cochlea. The most characteristic symptoms of AiSNHL at any age are episodes of sudden progression of hearing loss, fluctuations of hearing thresholds, and bilateral, often asymmetric impairments. The article presents contemporary ideas of the clinical and audiological manifestations of AiSNHL, the possibilities of diagnosing and treating the disease, and highlights the current approaches to (re)habilitation. Along with literature data, two own clinical cases of an extremely rare pediatric AiSNHL are given.

Recurrent sudden sensorineural hearing loss-A literature review

Objective

Sudden sensorineural hearing loss (SSNHL) is one of the few emergent otologic conditions. Although more than half of all patients would benefit from timely treatment, recurrence occasionally develops unexpectedly. The aim of our study is to evaluate the recurrence rate after SSNHL, and present the prognosis after first-episode and recurrent SSNHL.

Methods

A literature search was conducted of the PubMed and Embase electronic databases.

Results

Seven studies with a total of 3781 patients were included, and 96 patients experienced recurrence. The recurrence rate ranged between 1.4% and 17%. The average time to recurrence was about 2 years in most studies. The majority of the studies reported using systemic steroids for treating first-episode SSNHL, and one study used a plasma expander in patients with recurrent SSNHL. The recovery rate for first-episode patients was 58%-79%, while that for recurrent SSNHL ranged widely, from 21% to 86%. There were no common risk factors for SSNHL recurrence among the studies, although low-frequency hearing loss, the presence of tinnitus during follow-up, and an increased neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio have been proposed.

Conclusion

Understanding the recurrence rate, risk factors, and prognosis after recurrence of SSHNL is crucial for comprehensive medical care; in this respect, further prospective studies with long-term follow-up may be instructive.

Level of Evidence

4.