Studies of the dead have shown how COVID-19 affects the brain: the injuries are horrible

With the onset of the pandemic, we found out fairly quickly that COVID-19 attacks not only the respiratory system, but also the stomach, intestines and heart, increasing the likelihood of blood clots forming, writes sciencealert. com.

Now, with the pandemic lasting more than a year, full autopsies of people who have died from COVID-19 have revealed more information about the widespread inflammation and the damage to brain tissue it causes.

Some experts speculate that up to 50 percent. COVID-19 patients admitted to the hospital may experience neurological symptoms that make it difficult to perform even everyday activities such as cooking.

“We were very surprised. At first, we expected to see injuries caused by lack of oxygen, admitted Dr. Avindra Nathas, clinical director of the National Institutes of Health (NSI).” However, we have seen many sources of injuries, commonly associated with cerebrovascular accidents and neuroinflammatory diseases “.

The NSI researchers, including Dr. Myoung-Hwa Lee and A. Nath, thoroughly examined the brain tissues of 19 dead patients. The age of the coronavirus victims ranged from 5 to 73 years. Many of them had risk factors for severe coronavirus, such as diabetes and cardiovascular disease.

Using a powerful microscope based on magnetic resonance imaging technology, Mr. Lee and his team identified 10 patients with abnormalities in the brain. In a more detailed study, hyperintensities were observed in light samples from photographs of brain samples taken under a microscope. Fluorescence microscopy revealed that these spots were leaking fibrinogen (a protein in the blood).

In the brains of several patients, these spots were surrounded by T cells and special microglia of brain immune cells. Dark clots of clotted blood were also detected. They led the researchers to conclude that these patients experienced several mini-bleeds in the brain. These injuries are usually caused by inflammation of the brain.

“The small blood vessels in the brain were bleeding,” Nath told NPR. “But the bleeding was not uniform.”

By the way, the neurological symptoms caused by COVID-19 were not limited to people with more serious illnesses or comorbidities.

“We saw a group of young people who did not have the usual risk factors, but their members suffered strokes. We also had to deal with patients whose mental health had changed drastically, apparently without any logical explanation, “Benedict Michael, a neurologist at the University of Liverpool, told Nature in September.

The patients suffered hallucinations and developed psychosis. A 55-year-old woman began seeing lions and monkeys in her home and later believed that her friend or relative had been replaced by an identical imposter (Capgras syndrome).

Despite research to detect the virus in brain tissue, Ms Lee and her team found no traces of SARS-CoV-2, but the researchers said in their report: Although other studies found traces of coronavirus in the brain, such findings were rare and the amount of virus was small.

“So far, our results suggest that the lesions detected were probably not caused by the SŪRS-CoV-2 virus, which directly infected the brain,” said Nath. Most likely they were caused by the body’s inflammatory reaction to the virus, he explained.

Due to the small sample size and limited clinical information, the research team is not in a rush to draw conclusions yet. However, their findings are consistent with EEGs, which revealed encephalopathy in patients with COVID-19, a disorder of normal brain function that can be caused by swelling and inflammation in the brain. The results of the study also coincide with studies that found that the coronavirus can elicit another dangerous response in the immune system, which in some cases does more damage than the virus itself.

Researchers are concerned about the long-term effects of brain inflammation on human health, as the injuries are linked to memory loss and Alzheimer’s disease. Some patients already suffer from long-lasting neurological consequences, such as chronic fatigue and Guillain-Barré syndrome.

“In the future, we plan to investigate how COVID-19 damages blood vessels in the brain and whether these damages cause any symptoms in the short or long term,” Nathas said.

The researchers’ report was published in the New England Journal of Medicine.