Corona: Neurological symptoms remain
Early in the course of the Corona pandemic, it was found that it can come in Infected to neurological symptoms such as loss of smell and/or taste. According to a new study, the most Affected are also not after surviving COVID-19-disease free of complaints.
The number of people that rises to become infected with the Coronavirus SARS-CoV-2, and increases. By the pathogen-triggered disease COVID-19 is often relatively harmless, with symptoms such as fever, cough, and headache. In some people it also leads to neurological symptoms such as temporary loss of smell and sense of taste. Experts now report that subsequent neurological disease can occur.
Neurological symptoms and outages remain
Numerous studies have described neurological manifestations of COVID-19. The spectrum ranges of taste and smell seizures disorders to severe shock. Such as the German society for neurology (DGN) reported in a recent communication, showed an Italian work well, that almost 90 percent of the Affected complaint after the acute illness-free. In some cases, neurological symptoms, and failure to stay back.
The Spanish flu also resulted in permanent neurological problems. It is thus, in both cases to virus-mediated autoimmune reactions? The DGN, according to a neuro-found immunological working group of the Charité antibody findings indicate that the immune system in patients who are severely ill COVID-19-patients and in-patients, against the body’s own nerve cells.
Also young, “vascular healthy” people at risk
Various case reports and studies describe, in the meantime, Sufferers of neurological side effects at COVID-19 -. Very often it comes to smell and taste disorders. However, it may lead to seizures during viral infection is also diffuse brain damage (encephalopathies) with neurological and psychiatric disorders, to inflammation of the brain and spinal cord (encephalomyelitis) or to shock.
The Curious thing is that the Latter not only COVID-19-patients and in -patients occur, which have many cardiovascular risk factors, but also in young, “vascular healthy” people who have been infected with SARS-CoV-2.
Furthermore, it can occur as a result of the virus infection and also diseases of the peripheral nervous system such as Guillain-Barré syndrome. Based on these observations, the international trade world speaks now of the “Neuro-COVID”.
Complaints can remain
An American working group has at the end of June in the scientific journal “Journal of Alzheimer’s Disease“, Neuro-COVID-division into three stages presented, the files, the accompanying neurological symptoms according to their severity.
A work from the UK, which was published at the beginning of July in the medical journal “Brain”, has divided the symptoms of a neurological diagnosis group in five classes (1. The Brain Changes (Encephalopathy), 2. inflammatory diseases of the Central nervous system, 3. Ischemic Strokes, 4. peripheral neurological disorders and 5. other Central nervous system disorders).
“Still is for some of the neurological manifestations is not clear how often you are at COVID-19 really,” explains Professor Peter Berlit, Secretary-General of the DGN. “But even if the proportion corresponds to the percentage of only about the of SARS or MERS, is the absolute number COVID-19-associated neurological disorders in view of the enormously high infection rates in the world as a highly classified, what needs to be found in patients’ necessarily take into account.”
In addition, the finding that neurological symptoms commented often persistent, worrying. A recent study from Italy, which was published in the journal “JAMA”, examined whether and to what complaints at COVID-19-Patients after discharge from Hospital remained: 87 percent of those Affected in the aftermath of symptoms.
The most common neurological consequences were in this study, tiredness or Fatigue (about 53 percent), impairments of the sense of smell (about 16 percent), taste disturbance (approximately eleven percent), headaches (approximately ten percent), and dizziness (about five percent).
How the DGN writes, here is an interesting historical analogy: the Spanish flu in 1918, led in consequence to unexplained neurological complaints in which a decade over a Million people suffered (“encephalitis lethargica”, European sleeping sickness called). “This shows that a neurological follow-up of COVID-19-patients with accordingly, further diagnosis is enormously important,” says Professor Berlit.
Immune system is directed against nerve cells
The neuro invasive potential of corona virus has been described in 2002/2003, the SARS-CoV outbreak: at that Time, they found the virus only in the brain cells, not in neighboring blood or lymphatic vessels, which speaks of the vessels for a route of infection through the nerve cells and not via blood or lymph.
In the case of the new Coronavirus SARS-CoV-2, a direct virus detection in the CSF (cerebrospinal fluid) has succeeded so far, but only in individual cases. Hence, the hypothesis is that indirect viral-mediated mechanisms could play in the development of neurological symptoms a role. “Thus, the significant activation of the coagulation system in COVID probably explains-19, at least a portion of the impact,” explains seizures Professor Hans-Christoph Diener, spokesman of the DGN.
A study by the Berlin Charité under eleven investigated intensive care patients with COVID-19 and neurological symptoms to specific antibodies and was able to find: The immune system is obviously seriously ill COVID-19-patients against the body’s own nerve cells.
“The virus can stimulate the formation of auto-antibodies, the fit to the surface structure of nerve cells,” explains Prof. Dr. Harald Prüß of the Charité hospital in Berlin, a spokesman for the DGN Commission, neuro-immunology, has published this data on the medical Preprint-Server “medRxiv”.
“Currently, we check whether the anti-body formation is a consequence of virus-induced inflammation. Alternatively, it could be a “strategy” of the Virus, his surface body’s own structures to adapt to the killer cells of the immune system are not detected. In both cases, you are directed against all cells with this surface structure, also against healthy nerve cells. So the Virus can catalyze a neurological Symptom, or a neurological disorder,“ said the scientist.
This mechanism is also of other viruses are known, for example, herpes viruses can trigger in this way, an autoimmune Form of brain inflammation after viral infection.
“Not all of the Pathomechanisms have been clarified, the cause COVID-19-patients of a neurological involvement, we need more prospective evidence from larger patient numbers. The Prüß and colleagues suspected pathogenic process appears to be plausible and also has the charm that we have here a treatment option: In the case of virally-induced autoimmune reactions, we can treat successfully with immune therapies,“ explains DGN-Secretary-General Professor Berlit finally. (ad)