Clinical guidelines about COVID-19’s impact on the body beyond the lungs published
When COVID-19 first gained traction in the US, in early March 2020, there was little clinical guidance on treating the effects of the disease. Physicians on the frontline of the outbreak in New York quickly realised that COVID-19 was more than just a respiratory infection, and have since published a comprehensive review of the disease’s widespread effects on organ systems beyond the lungs.
Dr. Aakriti Gupta, a cardiology specialist deployed to COVID-19 intensive care units at Columbia University Irving Medical Center, observed that many patients “were clotting a lot, had high blood sugars even if they did not have diabetes, and were experiencing injury to their hearts and kidneys.” Gupta decided to combine the findings with what she and other physicians were learning at this time.
Together, they have created the first comprehensive clinical guidelines on COVID-19’s nonrespiratory symptoms, including the clinical presentation and treatment of children and pregnant women with the infection.
The guidelines highlight four mechanisms that could explain the unusual blood clotting and other complications among patients:
Direct damage to cells/tissues inflicted by the virus – there are tissues throughout the human body that carry receptors (angiotensin converting enzyme 2, or ACE2) especially vulnerable to SARS-CoV-2. These allow easy binding and entry of the coronavirus and subsequent infection or injury;
Damage to the endothelial cells that line blood vessels – the ACE2 receptors reside on endothelial cells that line the blood vessels supplying organs as well, and damage to these endothelial cells triggers inflammation and promotes the formation of blood clots (thrombosis). Clots impair the blood supply to tissues and can also break free/lodge elsewhere in the circulatory system, causing further blockages, inflammation, and tissue damage;
Disruption of the hormones in the renin-angiotensin-aldosterone system (RAAS) – the RAAS regulates key physiological processes in the body, including fluid and electrolyte balance, blood pressure, the permeability of blood vessels, and tissue growth. ACE2 strongly influences this system, so invasion by the coronavirus may disrupt its normal regulatory function and contribute to tissue damage in particular organs;
Dysregulation of the immune response – the physicians have noted that“elevated markers of inflammation, such as C-reactive protein, in the blood of people with COVID-19 are associated with more severe illness and mortality.” Clinical trials of drugs that target specific components of the immune response are underway to prevent fatal consequences of an overactive immune system.
“Beyond the life threatening pulmonary complications of SARS-CoV-2, the widespread organ-specific manifestations of COVID-19 are increasingly being appreciated. As clinicians around the world brace themselves to care for patients with COVID-19 for the foreseeable future, the development of a comprehensive understanding of the common and organ-specific pathophysiologies and clinical manifestations [of this multisystem disease] is imperative.”
