[Olfactory dysfunction in COVID-19, a review of the evidence and implications for pandemic management]

Neurological manifestations of COVID-19 in patients: from path physiology to therapy

Coronavirus is a family of ARN positive single-stranded belonging to the family of Coronaviridae. There are several families of coronavirus that transmit more or less serious diseases. However, the so-called coronavirus-19 (SARS-CoV2) is the one that is currently causing most of the problems; in fact, biological dysfunctions that this virus causes provoke damage in various organs, from the lung to the heart, the kidney, the circulatory system, and even the brain. The neurological manifestations caused by viral infection, as well as the hypercoagulopathy and systemic inflammation, have been reported in several studies. In this review, we update the neurological mechanisms by which coronavirus-19 causes neurological manifestation in patients such as encephalomyelitis, Guillain-Barré syndrome, lacunars infarcts, neuropsychiatry disorders such as anxiety and depression, and vascular alterations. This review explains (a) the possible pathways by which coronavirus-19 can induce the different neurological manifestations, (b) the strategies used by the virus to cross the barrier system, (c) how the immune system responds to the infection, and (d) the treatment than can be administered to the COVID-19 patients.

Anosmia and COVID-19: perspectives on its association and the pathophysiological mechanisms involved

With the spread of SARS-CoV-2, contingency measures and plans to facilitate the screening of infected patients are needed. Changes in olfaction have been cited as symptoms of the disease, and it is important to prove or exclude its association with this condition to refine the symptomatic criteria for early isolation. This article aims to analyze the association between olfactory disorders and SARS-CoV-2 infection as well as investigate the possible underlying pathophysiological mechanisms. The research was carried out using the PubMed, Science Direct, and LILACS databases on May 9, 2020, and updated on May 21. Combinations of MeSH descriptors and the Boolean operator, "AND," were used: coronavirus infections AND olfactory disorders, coronavirus infections, and neurological manifestations. A total of 1187 articles were found in the databases, of which 17 were included in the study. The data suggest that changes in smell are strongly associated with Covid-19, especially in women and patients with fever; these changes increase the degree of suspicion of Covid-19, and they warrant early implementation of isolation and surveillance measures. There are still gaps in the elucidation of the pathways involved in the loss of smell caused by SARS-CoV-2; however, the great affinity of the virus for ACE-2 receptors, which are present in large quantities in the nasal cavity and olfactory bulb, has been considered.