Some coronavirus patients are dying not from disease but their over-active immune system attacking their organs
The immune system usually fights invading microorganisms, but sometimes the system loses control and goes into overdrive, attacking the body itself, instead of the invader
Coronavirus has killed more than 160,000 people worldwide, some of whom died not directly from the virus -- but because their defenses deceived them. Under normal circumstances, the body's defense system or immune system does a good job fighting invading microorganisms -- maintaining order and control during the attack. Helping in the attack are proteins called cytokine. The immune system helps people recover.
But sometimes the immune system loses control and goes into overdrive, attacking the body itself, instead of the invader. The attack is thanks to the misguided cytokines, which direct an attack on the lungs. It stops functioning, leaving people gasping for breath. This condition is called a cytokine storm.
Cytokine storm is not restricted to COVID-19 alone. People battling the flu also suffer from an overactive defense system.
What does this look for COVID-19 patients?
According to Dr. Randy Q. Cron, from the University of Alabama in Birmingham, COVID-19 patients with overactive defenses tend to suffer more than the other COVID-19 patients. These patients have a fever. They lose their ability to breathe and need oxygen support, Dr. Cron told MEA WorldWide (MEAWW).
As patients become more ill with Covid-19 cytokine storm, the immune system begins attacking other organs. "There is a usually high percentage of clotting in the lungs, brain, and elsewhere," he added. Slowly, these organs start failing to function normally.
Patients with cytokine storm often experience confusion and seizures, Dr. Grant Schulert, from the University of Cincinnati College of Medicine, told MEAWW.
How does it affect children, young and old adults?
Generally, the new coronavirus is severe among older adults, but some young people die too.
Even during the 1918 Spanish flu pandemic, young people suffered severe disease, and experts think the overactive immune system could have some role in that. They suspect the same immune complication affected young patients with serious COVID-19 in Italy and China.
According to Dr. Cron, some children and young adults could suffer from an overactive immune system. Experts think that genes could be to blame for this and are trying to learn more. "Children, it seems that children are less likely to develop a significant cytokine storm compared to adults. We all hope this continues to be what is observed," Dr. Cron said.
Testing and treating an overactive immune system?
To screen for cytokine storm, doctors order a test that looks for a protein called ferritin. The idea is that people with overactive defenses release high levels of this protein. "I think that all COVID patients who are sick enough to be in the hospital should be screened for cytokine storm," Dr. Schulert said.
Once patients are diagnosed with the condition, they treat them with medications that soothe the immune system. One such drug is tocilizumab. Early studies suggest the drug is effective in treating these patients. China has approved the drug to treat severe COVID-19 cases, and a private company is testing the drug on hundreds of coronavirus patients in the US.
Experts will learn more in the days to come. For now, Dr. Cron said: "The earlier you treat the cytokine storm, the better your chances of effectively treating it."