By the bioMérieux Connection Editors
By now, it has been established that COVID-19 is not just any respiratory virus. Researchers have quickly discovered that it is capable of directly affecting multiple organ systems, and that it can also cause a host of related complications. Among those complications are endothelial dysfunction, sepsis, and acute kidney injury. Authors of an article in the Medico-Legal Journal, noted that, “Twenty percent of patients with SARS-CoV-2 infection have a critical disease, and many of these can be defined as septic, according to the Sepsis-3 criteria.”
In a review article in Frontiers in Physiology, published June 26, the authors suggested that there may be a relationship between endothelial dysfunction, cytokine storm, and sepsis in COVID-19 patients, although the possible mechanisms and sequence of events are not yet clear. The authors identified endothelial dysfunction and accompanying cytokine storm as the primary drivers of COVID-19 cases where disease progression is exceptionally fast and frequently lethal. Endothelial dysfunction occurs when the cells that make up the thin membrane around organs, called the endothelium, send incorrect signals that cause capillaries to close off blood flow to organs. Without blood flow, organs begin to fail.
Organ failure and dysfunction are defining characteristics of severe sepsis. The causes of organ dysfunction in sepsis patients are complex, but ultimately result in blood being unable to provide organs with the oxygen necessary for functioning. The current understanding of organ dysfunction with sepsis mainly relies on data from patients with bacterial sepsis, because it is vastly more common than viral sepsis. This is important because it represents a knowledge gap when it comes to studying COVID-19 and sepsis.
“A key difference between viral sepsis and either bacterial or fungal sepsis is that, for most viral infections, specific therapies are substantially less effective than antibacterial or antifungal agents,” notes an article in the Chest journal, published July 21. The authors argue that not only is there a relationship between COVID-19 and sepsis, but that severe COVID-19 can essentially be considered sepsis. In the same way that sepsis patients must be treated with prompt, appropriate antibiotic therapy, COVID-19 patients must receive appropriate antimicrobial therapy—except in this case, no clinically-proven therapy currently exists. (Remdesivir, which has Emergency Use Authorization from the FDA and is recommended by the NIH for use in COVID-19 patients needing oxygen supplementation, is also still undergoing clinical trials.) As a result, patients receive largely supportive care.
In this trial by fire, physicians have gained a better understanding of how to handle different aspects of viral sepsis and have improved best practices for supportive care. These have helped to improve survival rates for critically ill COVID-19 patients and will likely provide a foundation for better supportive care as new viruses inevitably arise. However, the situation highlights why antimicrobials are such a critical part of modern medicine. The authors of the Chest article conclude with an important point: “COVID-19 is sepsis caused by SARS-CoV-2, a virus for which there is little in the way of antimicrobial therapy. Because it is sepsis, known tenets of sepsis care and organ support must be our guiding principles. Surprisingly, a key lesson that we must take from the war on this viral sepsis is that we must redouble our efforts to be stewards of antimicrobials and ensure that we have adequate means to control bacterial and fungal infection.”
Join us for a bioMérieux sponsored webinar “Is COVID-19 Sepsis?” on October 8 at 5 PM CEST.
Opinions expressed in this article are not necessarily those of bioMérieux, Inc.