An increasing number of American children have developed a serious inflammatory condition related to coronavirus, and although most recovered, the potential for long-term or permanent damage is unknown, two new studies suggest.
The documents, published online Monday in the New England Journal of Medicine, provide the most comprehensive report on the condition.
The condition is known as multisystemic inflammatory syndrome in children. It is considered rare and deaths are rare; six children died among the 285 in the new studies.
Including cases in Europe, where it was first reported, around 1,000 children worldwide have been affected, an editorial in the magazine said.
The case definition from the Federal Centers for Disease Control and Prevention includes current or recent COVID-19 infection or exposure to the virus; fever of at least 100.4 for at least 24 hours; serious illness requiring hospitalization; inflammatory markers in blood tests and evidence of problems affecting at least two organs that could include the heart, kidneys, lungs, skin, or other nervous system.
Digestive symptoms, such as nausea and diarrhea, are common. Some children may have symptoms similar to Kawasaki disease, a rare condition in children that can cause swelling and heart problems.
At least 35 states have had cases, and they appear to emerge a few weeks after local COVID-19 spikes in activity, said Dr. Adrienne Randolph of Boston Children’s Hospital. She is principal investigator of a multistate study that includes scientists from CDC. The second document involved 99 children in New York State, where the first cases occurred in the United States.
Combined, the documents show 285 cases from March through mid-end May, but Randolph said additional American children were diagnosed in June.
Most had current or recent COVID-19 infections, but had previously been healthy.
About 80% of the children in the multistate study had heart-related problems, including coronary aneurysms, a lump in a heart artery that can be fatal.
“Those must be followed,” said Randolph. “This is a life-threatening concern for many patients.”
Most of the affected children had no other health condition, but about 30% were obese. The condition also appears to disproportionately affect Latino and black children and boys.
The average age was 8 years. The researchers don’t know if adults can be affected.
