Affordable Access

Access to the full text

Anosmia: a missing link in the neuroimmunology of coronavirus disease 2019 (COVID-19)

Authors
  • Yazdanpanah, Niloufar1, 2
  • Saghazadeh, Amene2, 1
  • Rezaei, Nima2, 3, 1
  • 1 Universal Scientific Education and Research Network (USERN), Iran , (Iran)
  • 2 Research Center for Immunodeficiencies, Tehran University of Medical Sciences, Children’s Medical Center, Dr. Qarib St, Keshavarz Blvd , (Iran)
  • 3 Tehran University of Medical Sciences, Iran , (Iran)
Type
Published Article
Journal
Reviews in the Neurosciences
Publisher
De Gruyter
Publication Date
Aug 10, 2020
Volume
31
Issue
7
Pages
691–701
Identifiers
DOI: 10.1515/revneuro-2020-0039
Source
De Gruyter
Keywords
License
Yellow

Abstract

Just before 2020 began, a novel coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), brought for humans a potentially fatal disease known as coronavirus disease 2019 (COVID-19). The world has thoroughly been affected by COVID-19, while there has been little progress towards understanding the pathogenesis of COVID-19. Patients with a severe phenotype of disease and those who died from the disease have shown hyperinflammation and were more likely to develop neurological manifestations, linking the clinical disease with neuroimmunological features. Anosmia frequently occurs early in the course of COVID-19. The prevalence of anosmia would be influenced by self-diagnosis as well as self-misdiagnosis in patients with COVID-19. Despite this, the association between anosmia and COVID-19 has been a hope for research, aiming to understand the pathogenesis of COVID-19. Studies have suggested differently probable mechanisms for the development of anosmia in COVID-19, including olfactory cleft syndrome, postviral anosmia syndrome, cytokine storm, direct damage of olfactory sensory neurons, and impairment of the olfactory perception center in the brain. Thus, the observation of anosmia would direct us to find the pathogenesis of COVID-19 in the central nervous system, and this is consistent with numerous neurological manifestations related to COVID-19. Like other neurotropic viruses, SARS-CoV-2 might be able to enter the central nervous system via the olfactory epithelium and induce innate immune responses at the site of entry. Viral replication in the nonneural olfactory cells indirectly causes damage to the olfactory receptor nerves, and as a consequence, anosmia occurs. Further studies are required to investigate the neuroimmunology of COVID-19 in relation to anosmia.

Report this publication

Statistics

Seen <100 times