Recent pathogenetic aspects of hearing loss in COVID: A literature review

Abstract

The World Health Organisation predicts that by 2050, up to 10% of the world's population will need rehabilitation to address disability-related hearing loss. The purpose of this study was to identify the main mechanisms of hearing loss associated with Severe Acute Respiratory Syndrome Coronavirus 2 infection. The study included modern English-language scientific publications, mainly those with a high citation index, through the professional platforms MEDLINE/PubMed and Index Medicus. A total of 48 sources were selected. Research papers devoted to the development of conductive or sensorineural hearing loss, which occurred directly as a result of a viral disease, or is associated with the processes that accompany it (treatment, concomitant pathology, vaccination, etc.), were analysed. It was found that the development of viral-induced hearing loss in COVID has a multifactorial nature. The heterogeneity of audiological changes is primarily conditioned by direct viral damage to auditory analyser cells that express membrane receptors of the angiotensin converting enzyme of the second type. In addition, there is a reactivation of latent viral infection, extravasation of exudate into the middle ear cavity, blood clotting disorders, immune-mediated cell damage, local and generalised inflammatory reactions that affect both sound conduction and sound perception in one ear or both. Some cases of audiological disorders may also be of iatrogenic origin, since post-vaccination complications and ototoxic effects of medications used in the treatment of COVID-19 are not excluded, which should be considered by clinicians at all levels of healthcare to effectively manage a specific clinical scenario