Immunological Mechanisms of Sensorineural Hearing Impairment in Patients with Different Clinical Phenotypes of Chronic Rhinosinusitis: A Narrative Review.

Background: In this review article, we aimed to discuss the pathogenesis of sensorineural hearing loss (SNHL) in patients with different forms of chronic rhinosinusitis (CRS), with special reference to the connection of the immune response of the nasal and middle ear mucosa and inner ear structures.

Methods: Articles for this review were identified using PubMed and Google© Scholar databases.

Results: Different phenotypes of CRS may be associated with impaired function of the inner and outer cells of the organ of Corti. This is primarily due to the secondary CRS, which occurs within systemic diseases, such as granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (EGPA). Also, the tetrad, which includes CRS with nasal polyps, non-allergic asthma, hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs), and so-called eosinophilic otitis media can lead to SNHL.

Conclusion: Previous studies suggest that disrupted harmony between the immune response in the nasal and middle ear mucosa and inner ear structures may contribute to developing SNHL in CRS patients. This especially applies to CRS as part of NSAID-exacerbated respiratory disease and systemic necrotizing vasculitis, including GPA and EGPA. However, the exact mechanisms of development of SNHL in different forms of CRS have not been sufficiently investigated and new studies are necessary soon. Apart from the pathophysiological basis of SNHL, different therapeutic approaches in the clinical phenotypes of CRS have also been discussed.