Post COVID and Apheresis - Where are we Standing?

A continual increase in cases of Long/Post COVID constitutes a medical and socioeconomic challenge to health systems around the globe. While the true extent of this problem cannot yet be fully evaluated, recent data suggest that up to 20% of people with confirmed SARS-CoV-2 suffer from clinically relevant symptoms of Long/Post COVID several weeks to months after the acute phase. The clinical presentation is highly variable with the main symptoms being chronic fatigue, dyspnea, and cognitive symptoms. Extracorporeal apheresis has been suggested to alleviate symptoms of Post/COVID. Thus, numerous patients are currently treated with apheresis. However, at present there is no data from randomized controlled trials available to confirm the efficacy. Therefore, physicians rely on the experience of practitioners and centers performing this treatment. Here, we summarize clinical experience on extracorporeal apheresis in patients with Post/COVID from centers across Germany.

COVID-19 and Therapeutic Apheresis.

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is an unprecedented challenge for the global community. The pathogenesis of COVID-19, its complications and long term sequelae (so called Long/Post-COVID) include, in addition to the direct virus-induced tissues injury, multiple secondary processes, such as autoimmune response, impairment of microcirculation, and hyperinflammation. Similar pathological processes, but in the settings of neurological, cardiovascular, rheumatological, nephrological, and dermatological diseases can be successfully treated by powerful methods of Therapeutic Apheresis (TA). We describe here the rationale and the initial attempts of TA treatment in severe cases of acute COVID-19. We next review the evidence for the role of autoimmunity, microcirculatory changes and inflammation in pathogenesis of Long/Post COVID and the rationale for targeting those pathogenic processes by different methods of TA. Finally, we discuss the impact of COVID-19 pandemic on patients, who undergo regular TA treatments due to their underlying chronic conditions, with the specific focus on the patients with inherited lipid diseases being treated at the Dresden University Apheresis Center.

COVID-19 and Lipid Disorders.

An elevated cholesterol concentration has been suspected to increase the susceptibility for SARS-COV-2 infection. Cholesterol plays a central role in the mechanisms of the SARS-COV-2 infection. In contrast, higher HDL-cholesterol levels seem to be protective. During COVID-19 disease, LDL-cholesterol and HDL-cholesterol appear to be decreased. On the other hand, triglycerides (also in different lipoprotein fractions) were elevated. Lipoprotein(a) may increase during this disease and is most probably responsible for thromboembolic events. This lipoprotein can induce a progression of atherosclerotic lesion formation. The same is suspected for the SARS-COV-2 infection itself. COVID-19 patients are at increased risk of incident cardiovascular diseases, including cerebrovascular disorders, dysrhythmias, ischemic and non-ischemic heart disease, pericarditis, myocarditis, heart failure, and thromboembolic disorders. An ongoing lipid-lowering therapy, including lipoprotein apheresis, is recommended to be continued during the COVID-19 disease, though the impact of lipid-lowering drugs or the extracorporeal therapy on prognosis should be studied in further investigations.

Is There a Role for Environmental and Metabolic Factors Predisposing to Severe COVID-19?

The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic affects people around the world. However, there have been striking differences in the number of infected individuals and deaths in different countries. Particularly, within Central Europe in countries that are similar in ethnicity, age, and medical standards and have performed similar steps of containment, such differences in mortality rates remain inexplicable. We suggest to consider and explore environmental factors to explain these intriguing variations. Countries like Northern Italy, France, Spain, and UK have suffered from 5 times more deaths from the corona virus infection than neighboring countries like Germany, Switzerland, Austria, and Denmark related to the size of their respective populations. There is a striking correlation between the level of environmental pollutants including pesticides, dioxins, and air pollution such as NO2 known to affect immune function and healthy metabolism with the rate of mortality in COVID-19 pandemic in these European countries. There is also a correlation with the use of chlorination of drinking water in these regions. In addition to the improvement of environmental protective programs, there are possibilities to lower the blood levels of these pollutants by therapeutic apheresis. Furthermore, therapeutic apheresis might be an effective method to improve metabolic inflammation, altered vascular perfusion, and neurodegeneration observed as long-term complications of COVID-19 disease.