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VOLUME 1 , ISSUE 2-4 ( April-December, 2022 ) > List of Articles


Olfactory and Gustatory Dysfunction in Patients with COVID-19

Osman Sinanović

Keywords : COVID-19, Etiopathogenesis, Gustatory dysfunction, Olfactory dysfunction, Treatment

Citation Information : Sinanović O. Olfactory and Gustatory Dysfunction in Patients with COVID-19. 2022; 1 (2-4):229-236.

DOI: 10.5005/jp-journals-11005-0038

License: CC BY-NC 4.0

Published Online: 20-03-2023

Copyright Statement:  Copyright © 2022; The Author(s).


Introduction: Infection with the new coronavirus [severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)] was first registered in December 2019 in China and then later spread rapidly to the rest of the world. On 31st December 2019, the World Health Organization on 11th March 2020 declared a pandemic with this virus. In Bosnia and Herzegovina, the first infected person was registered on 5th March 2020 in Banja Luka. Aim: To present some aspects of the olfactory and gustatory dysfunction in patients with the coronavirus disease of 2019 (COVID-19). Methods: The article has an analytical character and review of the literature. Results and Discussion: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a high similarity with SARS-CoV-1 and uses the same receptors to enter the human body [angiotensin-converting enzyme 2 (ACE2)].2 COVID-19 is a respiratory infection that is primarily transmitted via respiratory droplets. In the first year of the pandemic, the SARS-CoV-2 coronavirus has mutated several times, resulting in genetically different variants. The variants are named by using letters of the Greek alphabet. The Alpha variant (Wuhan, China), Beta variant (first outbreak in South Africa), the Gamma variant (first outbreak in Brazil), and the Delta variants (first outbreak in India and Omicron variant) have caused an increase in cases worldwide. Typical symptoms of COVID-19 infection can be very moderate to very severe, with severe respiratory symptoms and fatal outcomes. COVID-19 is primarily a disease of the respiratory system, but SARS-CoV-2 also penetrates the central nervous system (CNS) and apparently could be responsible for fatal outcomes in some cases. The entry of the virus into the brain can lead to different neurological and psychiatric manifestations, including headache, loss of smell (anosmia) and the loss of taste (ageusia), encephalopathy, encephalitis, paresthesia, myalgia, Guillain-Barre syndrome, and cerebrovascular diseases. Conclusion: The coronavirus disease of 2019 (COVID-19) is primarily a disease of the respiratory system, but SARS-CoV-2 also penetrates the CNS, leading to serious neurological disorders, and apparently, it is also responsible for mortality. The frequency of anosmia and ageusia in patients with COVID-19 varies widely, from 10 to 65%, being the primary symptom in about 12% of patients. Most of the analyzed subjects reported olfactory recovery. However, anosmia and ageusia can last several months or even longer. For now, the etiopathogenesis of anosmia and ageusia in SARS-CoV-2 infection is still unknown. Nasal or systemic corticosteroids were recommended in the acute phase as well as olfactory training (sniffing the smell of rose, lemon, and cloves) in the acute and chronic phases, and many other drugs as potential therapeutics.

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