To date, 70 children have fallen ill with hyperinflammation as a result of a covid-19 infection in Sweden.

- These are seriously ill children, everyone must receive specialized inpatient care and about 15 to 20 children have needed intensive care, but no child has died in Sweden, says Petter Brodin, pediatrician at Karolinska University Hospital and immunologist at Karolinska Institutet.

Abdominal pain

The first symptoms are usually abdominal pain, nausea and high fever and some children are confused and slow in thought.

Another group has skin rashes and red eyes.

Some suffer from shock conditions due to severely impaired heart function and declining blood pressure and such children need intensive care.

Typically, the inflammatory condition occurs one to two months after the covid-19 infection itself, which in turn may have been so mild that the children barely noticed it.

In several cases, only one parent has had symptoms and then the children fall ill one to two months later.

Survey

Petter Brodin has now, together with Italian researchers, made the first survey of how the immune system behaves in children who suffer from this serious inflammatory condition after covid-19 and has published its results in Cell.

They have compared blood samples from children suffering from another similar disease called Kawasaki disease, as well as adults suffering from severe inflammation during ongoing covid-19.

- We can see that it is about three completely different types of inflammation.

This, MIS-C, which affects children, is a completely new inflammatory condition, says Petter Brodin.

No risk factors

Today, children are treated with very high doses of cortisone and biological drugs that inhibit specific parts of the immune system and the children seem to respond very well to this treatment.

Now they want to go further and find out why a small group of children get so sick after Covid-19.

So far no risk factors are known.

- What we know now is that the majority of children are completely healthy before they fall ill with this, says Petter Brodin.

The disease is called MIS-C which is an abbreviation of: Multisystem Inflammatory Syndrome in Children associated with COVID-19 (MIS-C).