CHICAGO — When attempting to predict who will end up in the ICU with COVID-19, the answer flows in the blood. Until now, there was no definitive way to chart a patient’s course, but there are known risk factors, like obesity, high blood pressure and diabetes.
Dr. Hyung Chun is among the Yale researchers hoping to change that.
“As you know there is such a wide spectrum of disease from patients who are completely asymptomatic to other patients who have prolonged course and ultimately may die from the disease,” Chun said.
But with a simple blood draw, researchers struck gold.
“What we focused on were these proteins circulating in the blood,” Chun said.
They identified five key proteins in the blood were elevated in the COVID-19 patients who went on to become critically ill.
Matthew Meizlish, is a MD-PhD student at Yale.
“We used blood samples collected within 24 hours of arriving at the hospital. We saw these same five proteins are actually elevated on day one of hospitalization,” he said. “And the really remarkable thing is they predicted which of the patients who were initially not severely ill – which of those would ultimately become critically ill and ultimately go to intensive care unit.”
The predictive proteins are associated with what’s called neutrophils – a type of white blood cell.
“They are one of the first lines of defense against infection,” Meizlish said.
The counts remained low in those who never developed severe illness.
“We think that it’s very possible neutrophils are actually driving a lot of this severe disease,” Meizlish said. “And one of the reasons we think that is even though neutrophils are great defenders against pathogens like bacteria and viruses, they cause a lot of collateral damage. They are not precision fighters, they can really wreak havoc in the tissue.”
The neutrophils are necessary for the body to mount an early response to SARS-CoV-2, but in the later stages they add to the damage in the body. So, blocking the activation of the neutrophils and tamping down the inflammation may be the target for new and known therapies for earlier intervention and better outcomes.
“Hopefully, what we’re contributing to the field at the moment will hopefully one day turn into better ways to diagnose and treat these patients,” Chun said.
The researchers hope to confirm their findings in future clinical studies with the goal of developing a diagnostic blood test that could be used regularly in the hospital setting to help determine which patients will require more intense interventions.