CHARACTERISTICS AND DYNAMICS OF NEUROLOGICAL DISORDERS AFTER COVID-19 INFECTION

Abstract

In the review, literature presents data on neurological disorders and complications after a sustained COVID-19 infection. In the initial stages of the pandemic, headache, weakness, impaired sense of smell, cognitive dysfunction were mainly recorded, then cases of ischemic strokes, thromboembolism, dementia, acute inflammation, which indicated a specific viral damage to the vessels of the brain and hemocoagulation systems, encephalopathy were registered later, demyelinating injuries, mental disorders. Many factors and mechanisms may underlie neurological manifestations, including possibly immune reactions, when the virus damages nerve and microvascular cells and induces the formation of new neuron-specific autoantigens to which autoimmune reactions develop, and inflammatory reactions that determine the clinical course of neurological disorders. Neurological and mental disorders with different manifestations occur both in patients in the acute phase of the disease, which requires inpatient treatment, as well as in a significant part of infected persons who did not require hospitalization for pneumonia and were treated on an outpatient basis, in patients who had a mild course of the disease, various complications also developed after clinical recovery, which received the name «prolonged covid syndrome» or «consequences after acute covid», «Long Covid». Dynamic follow-up of patients over 6-8 and 18 months showed that the resulting nervous disorders may partially or completely disappear, while others persist for a long time. Almost all symptoms after 18 months were detected in a smaller number of observations, but the frequency of smell and taste disorders probably only decreased, almost by 2-2.5 times, which indicates, as some that is, the gradual restoration of the functions of the nervous system and reducing neuro covid symptoms. The review analyzes in detail some of the causes and mechanisms of the development of Long Covid, special attention is paid to autoimmune reactions that are activated during Covid-19, namely antigenic mimicry, the similarity of the virus and human proteins, the cytotoxic effect of anti-covid immunoglobulins, inhibition of autoimmunity reactions. The review notes that many issues of the development of neurological disorders require further study and improvement of treatment and rehabilitation methods. Keywords: Covid 19, Long Covid, neurological manifestations and complications.