Sepsis occurs when a patient has an overwhelming reaction to an infection and is associated with high morbidity and mortality rates. The infection causes an individual’s immune system to mount an extreme response. Sepsis is far more damaging to the patient’s own body than a typical immune response to infection. This excessive response can very rapidly result in tissue damage, organ failure, and even death if not promptly treated. Any infection can lead to sepsis, including infections caused by bacteria, viruses, fungi, and parasites [1]. COVID-19, too, can lead to sepsis and it is critical to understand how best to prevent or treat it in this context.
The term sepsis or septicemia originated in 1914, and the definition of sepsis has evolved over time given the various complications of the condition. Sepsis usually results from a systemic inflammatory response syndrome following an infection. However, not all cases of sepsis necessarily manifest symptoms of systemic inflammation, especially in elderly individuals. The new 2016 definition of sepsis is that of life-threatening organ dysfunction resulting from a dysregulated host response to an acute infection [2].
Viral sepsis has a number of differences compared to bacterial sepsis. In bacterial sepsis, systemic inflammation affecting multiple organs is more dominant than in sepsis caused by viral infection, like COVID-19. Furthermore, while bacterial sepsis causes an early and sudden onset clinical deterioration, viral diseases may have a relatively late onset and a longer course [3].
Common signs of sepsis, such as fever, chills, difficulty breathing, pain, or confusion, are usually experienced by individuals with severe cases of COVID-19. This may impair the detection of sepsis. Data obtained from hospitalized COVID-19 patients and autopsies have revealed additional features of sepsis, including the activation of the complement system, the activation of coagulation, immune cell reprogramming, eicosanoid storms, cytokine storms, immunosuppression with T-cell exhaustion, and massive widespread cell death in a host. Dysfunction of the respiratory system caused by lung damage is the leading cause of death in COVID-19 patients. Therefore, in the medical community, the possibility that a severe COVID-19 case could progress to sepsis is seriously taken into consideration [4]. Consideration of severe COVID-19 disease as a sepsis syndrome has relevance to and may help determine the best treatments to modulate the immune response, limit intrinsic damage to tissue and organs, and improve outcomes [3].
It is important to note that, conversely, sepsis survivors are at higher risk of contracting infections within a few months of their recovery. This includes any infection, including COVID-19. However, many individuals who contract COVID-19 recover without any further medical problems [5].
Understanding and proactively preventing or treating sepsis in the worst cases of COVID-19 will continue to be critical in order to minimize the morbidity and mortality of this disease.
References
1. What is the connection between COVID-19 and sepsis? | National Academies. Available at: https://www.nationalacademies.org/based-on-science/what-is-the-connection-between-covid-19-and-sepsis. (Accessed: 16th October 2023)
2. Singer, M. et al. The third international consensus definitions for sepsis and septic shock (sepsis-3). JAMA – Journal of the American Medical Association (2016). doi:10.1001/jama.2016.0287
3. Koçak Tufan, Z., Kayaaslan, B. & Mer, M. COVID-19 and Sepsis. Turkish journal of
medical sciences (2021). doi:10.3906/sag-2108-239
4. Zhang, Y. & Han, J. Rethinking sepsis after a two-year battle with COVID-19. Cellular and Molecular Immunology (2022). doi:10.1038/s41423-022-00909-7
5. Coronavirus (COVID-19) | Sepsis Alliance. Available at: https://www.sepsis.org/sepsisand/coronavirus-covid-19/. (Accessed: 16th October 2023)