By: dr. Lisa Andriani L, M.Biomed
Since its emergence in late 2019, the SARS-CoV-2 virus has become the most feared infectious agent and has had a severe impact on various sectors. What is feared about this virus is the nature of the disease which is difficult for clinicians to predict. In some individuals, this virus does not even cause symptoms, but in others it can cause severe symptoms, respiratory failure and even death. After several months of being acquainted with the COVID-19 disease, clinicians and researchers have only just obtained information on several comorbid factors that can worsen SARS-CoV-2 virus infection, including chronic diseases such as diabetes, hypertension, chronic lung disease, obesity and others, but this also does not fully answer the questions that arise. Stories of people who have received negative results from nasopharyngeal or oropharyngeal swab tests, who of course are considered cured of COVID-19 but actually get worse and die, are certainly often read or heard. So how does this virus actually cause severe illness or death?
Until mid-November 2021, within 1 year and 11 months, there have been 249.343.498 cases of Covid-19 recorded worldwide and caused 5.045.077 deaths (2%). In Indonesia itself, there were 4.246.802 cases recorded until November 5, 2021 with a death toll of 143.500 (3,4%).
From his research using the autopsy method on patients who died with a diagnosis of COVId-19, Sefer Elezkurtaj et al from Germany reported that patients generally died due to sepsis and failure of several organs at once. The most common symptom is respiratory failure. The autopsy results also found that there was also co-infection with bacteria, blockage of blood vessels in the lungs, extensive lung damage, heart failure, and some were found to have gastrointestinal bleeding. Comorbidities suffered by patients who died in Elezkurtaj's study included hypertension, chronic heart or kidney disease and also chronic lung disease. The autopsy also found atherosclerosis in the coronary blood vessels, heart enlargement, and chronic lung damage.
In their scientific review, Himayani et al. stated that SARS-CoV-2 virus infection has an effect on several organs such as the lungs, heart and blood vessels, kidneys, gastrointestinal, liver, nervous system, eyes, skin and even the patient's psychology. Most cases of SARS-CoV-2 infection experience respiratory failure and must be assisted with a ventilator. In normal lung tissue, it turns out that 83% of cells in the lungs have ACE-2 receptors (Angiotensin Converting-Enzyme-2), because ACE-2 is the entry point for the virus into human cells, cells that have ACE-2 will be the location where the virus multiplies. As a result, extensive cell damage and inflammation will also occur. As a result of inflammation and damage, fluid can build up in the lungs and reduce lung function.
The main cause of heart problems in COVID-19 is blood vessel disorders that cause plaque formation and thrombosis, blockages and blood vessel disorders cause reduced oxygen supply to the heart. Systemic inflammation that occurs in response to cytokine storms also causes inflammation of the heart to the point of causing heart failure or heart rhythm disturbances. Blood vessel disorders that occur can also occur in blood vessels in various organs, causing the organ in question to experience ischemia or decreased blood and oxygen supply to the organ.
ACE-2 receptors are also found in the kidneys, so the SARS-CoV-2 virus can also infect kidney cells. Cytokine storms as a body reaction can cause a decrease in the supply of oxygen and nutrients to kidney cells and result in Acute Kidney Injury (AKI). Symptoms in the gastrointestinal tract can also be caused by virus invasion into cells in the digestive tract, generally the symptoms that arise are nausea, vomiting, diarrhea, abdominal pain, or loss of appetite. Viruses or virus fragments are often found in the patient's feces.
Symptoms related to the nervous system are also often reported to occur with SARS-CoV-2 infection, including loss of smell or taste, headaches and seizures. Some patients have also been reported to experience meningitis and encephalitis, indicating viral invasion of the central nervous system. The cytokine storm that occurs also causes brain inflammation and edema that can cause seizures. Stroke can also occur due to blockage of cerebral arteries, where this blockage is caused by thicker blood conditions and injury or wounds to the endothelial lining of blood vessels.
In addition to internal organs, the effects of SARS-CoV-2 virus infection can also affect the eyes or skin. The eyes themselves are known to have ACE receptors, in addition to the eyes themselves being the entry point for the virus into the body. The presence of conjunctivitis or red eyes due to inflammation has also been reported in about a third of hospitalized patients. Common skin symptoms include rashes, urticaria (bumps similar to mosquito bites) or the appearance of small blisters filled with fluid similar to chickenpox.
One of the bases that strengthens the suspicion that SARS-CoV-2 virus infection not only has an impact on breathing but also has an impact on blood vessels is a study reported last October, Rauti et al reported that proteins from the SARS-CoV-2 virus cause disruption of endothelial function (the innermost layer of the blood vessel structure), so there is indeed a lot of clinical evidence that supports that COVID-19 is a disease that also disrupts blood circulation function so that it has an impact on many organs, supported by Spike protein a virus that is capable of infecting various organs of the body as long as the cells of those organs have ACE-2 receptors which are also spread throughout various organs of the body.
REFERENCES
- Effects of SARS-CoV-2 Virus Infection on Organs. Himayani R et al. Medula. April 2021:11(1): 43-47
- Rauti R et al. Effect of SARS-Co-V-2 proteins on vascular permeability. eLife 2021;10:e69314
- https://covid19.go.id/
- https://www.worldometers.info/coronavirus/
- Elezkurtaj, S., Greuel, S., Ihlow, J. et al. Causes of death and comorbidities in hospitalized patients with COVID-19. Sci rep 11 4263 (2021).
Note:
- Sepsis: a condition of a generalized inflammatory response triggered by the spread of infection (disease agents or their toxins) through the bloodstream, potentially life-threatening, and characterized by fever, chills, rapid breathing and pulse, decreased blood pressure, and organ failure.
- Cytokine storm: the uncontrolled release of cytokines (a type of protein produced by cells, especially immune cells, and which has the function of regulating or influencing the immune system in addition to being a medium for communication between cells) from the body due to an excessive immune system response.
