A rare inflammatory condition hits some children who have COVID-19

(NIH | NIAID)

Dozens of U.S. children have been hospitalized with a serious inflammatory condition possibly linked with the coronavirus and first seen in Europe.

New York authorities announced Wednesday that 64 potential cases had been reported to the state. The advisory followed an alert earlier this week about 15 cases in New York City.

A few other U.S. children have been affected during the pandemic, including a 6-month-old infant in California diagnosed with COVID-19 and Kawasaki disease, a rare condition that causes swelling in blood vessels.

Fever, abdominal pain and skin rashes are common symptoms, while some New York children have developed heart inflammation requiring intensive care. Most had evidence of current or past coronavirus infections. 

Medical groups in Britain, Italy and Spain warned doctors last month to look out for the condition.

>Doctors probe link between COVID-19 and kids with Kawasaki disease

Some doctors say the New York cases increase the likelihood that the syndrome is a rare complication of COVID-19 although that remains to be proven.

"It raises our antenna a bit and tells is we need to be vigilant about unusual and more severe complications of COVID-19" in children, said Dr. Larry Kociolek, an infectious disease specialist at Lurie Children's Hospital in Chicago.

In a news release Wednesday, the American Heart Association emphasized that the condition is rare.

"We want to reassure parents — this appears to be uncommon. While Kawasaki disease can damage the heart or blood vessels, the heart problems usually go away in five or six weeks, and most children fully recover," said Dr. Jane Newburger, an association member and director of the Kawasaki Program at Boston Children's Hospital.

At least 3,000 U.S. children are diagnosed with Kawasaki disease each year. It's most common in kids younger than 6 and in boys. It was first reported in Japanese children and occurs worldwide.

The unusual syndrome prompted a conference call last weekend with researchers, doctors and U.S. and international health officials, the Kawasaki Disease Foundation said in a statement Thursday. The participants concluded that affected children should be treated by specialists at hospitals where intensive care is readily available since some children with the inflammatory condition become sicker rapidly.

Doctors still believe that most children with COVID-19 develop only mild illness. 

Most published research on the coronavirus in kids is from China and does not include mention of the inflammation syndrome. 

Dr. Sonja Rasmussen, a former U.S. Centers for Disease Control and Prevention specialist now at the University of Florida, said more published data are needed to clarify how COVID-19 affects U.S. children and that the possibility of severe disease should not be dismissed.

''I don't think we can be complacent about COVID-19 in children," Rasmussen said.

Dr. Sean O'Leary, a member of the American Academy of Pediatrics' infectious disease committee, said scientists and doctors in the U.S. and other countries are collaborating to better understand the inflammatory condition. But he emphasized that it has not been reported in most children with the coronavirus.

"This is not something parents need to panic about," he said.

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