Scientists have found a link between COVID-19 and cerebrovascular damage. Neurophysiological research published in the New England Journal of Medicine.
Coronavirus does not penetrate the brain tissue, but it weakens the walls of small vessels inside it, which can affect bleeding and strokes.
Avindra Nath, one of the authors of the work, a researcher at the National Institute of Neurological Disorders and Stroke (USA), explained that this is due to inflammatory reactions that are associated with the penetration of the virus into the body.
During the study, Nat and his colleagues decided to find out how SARS-CoV-2 can enter the human brain and disrupt its work. They studied how the state of the circulatory system of the brain changed in several dozen patients with coronavirus who died between March and July this year. Initial analysis indicated that their deaths were related to brain damage.
MRI scans showed many foci of inflammation and minor bleeding in the brain, the walls of small capillaries and other vessels have become permeable to blood and proteins contained in it. Specialists examined sections of these departments. “We expected to see traces of damage from infection and chronic oxygen deprivation. Instead, there was a lot of small damage to the nervous tissue, which usually occurs after strokes or brain inflammation,” explained Nat.
The virus was not found either in the brain of the patients or in its vessels. It turned out that the capillaries of the brain collapsed not due to infection with SARS-CoV-2, but because of the very high activity of the immune system: it began to attack not only the virus, but also healthy cells of the blood vessels. As a result, “holes” appeared there, some of which were filled with blood clots and microglia.
Scientists now have to figure out how long the damage to the blood vessels in the brain persists and find a therapy that can prevent or eliminate them.
Previously, Associate Professor of the Department of Psychology and Pedagogy of the 1st St. Petersburg State Medical University named after Pavlov, occupational therapist Maria Maltseva revealed the consequences that the coronavirus may have on the human brain. According to her, patients with COVID-19 may experience delirium.