In Los Angeles, doctor's at Children's Hospital are treating three young patients with the condition and they expect to see more.
The condition is similar to Kawasaki Disease, a rare, complex syndrome that turns a child's immune system against its blood vessels.
And that could lead to permanent heart damage. There is a risk of having coronary artery problems for life.
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In the United States, about 5,500 cases of Kawasaki Disease are diagnosed each year. But like many pediatric hospitals around the world, Children's Hospital Los Angeles is seeing an uptick in cases compared to the previous two years.
Dr. Jacqueline Szmuszkovicz, who has studied Kawasaki Disease, said the three children at Children's Hospital being treated all tested positive for antibodies to COVID-19, meaning they likely had the novel coronavirus some time before developing Kawasaki symptoms.
"And now their immune system is responding with inflammation," she said. "That's leading to a syndrome."
Szmuszkovicz says the connection has led to a new diagnosis called PIMS, for Pediatric Inflammatory Multi-System Syndrome.
Kawasaki symptoms include: persistent high fever, rash, red cracked lips, red tongue, swollen eyes, hands and feet, and enlarged lymph nodes in the neck.
The three children being treated at CHLA are all doing well and are being given customized treatment plans. Doctors are now looking into other recent Kawasaki cases to see if these patients were also exposed to COVID-19.
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