As the COVID-19 pandemic wears on, New Jersey is among regions dealing with several pediatric cases of mysterious symptoms that are similar to Kawasaki disease, a condition that causes inflammation in blood vessels.

The first in-state cases were confirmed among young patients at two of New Jersey’s pediatric hospitals — Bristol-Myers Squibb Children’s Hospital at Robert Wood Johnson University Hospital and Joseph M. Sanzari Children's Hospital at Hackensack University Medical Center.

Out of five children admitted in New Brunswick, three remain in intensive care, as first reported by NJ.com and confirmed by RWJUH spokesman Robert Cavanaugh.

Another five children were separately admitted in Hackensack, according to NorthJersey.com, with symptoms that included inflammation of the heart, liver failure and kidney failure. All five were treated and have been discharged, over a span between March and this week.

As of Thursday night, NorthJersey.com reported, there were also two children treated at St. Joseph's University Medical Center in Paterson and one child at Morristown Medical Center.

What is being seen appears to be a post infectious complication, according to Rutgers New Jersey Medical School Pediatrics Department Professor Glenn Fennelly.

This is a newly recognized pediatric multi-system inflammatory syndrome associated with COVID-19, which has overlapping symptoms to the relatively rare Kawasaki disease, Fennelly said.

In addition to at least 10 cases in New Jersey, there were at least 64 cases among pediatric patients in New York by Wednesday night, as confirmed by New York state health officials. There also have been cases in the UK, France, Italy and Spain.

"The assumption here is it could be an autoimmune or hyperimmune response, which has been has been the assumption with Kawasaki disease, as well," Fennelly said.

Kawasaki disease is clinically recognizable, which means there is no test to confirm its presence.

Young patients present a fever in addition to redness of the eyes, body rash, possibly cracked or red lips and/or a swollen tongue, possible swelling of fingers and swollen lymph nodes, Fennelly said.

A major medical center that treats children typically would see upwards of six cases in a year, Fennelly said and while Kawasaki disease is relatively rare, the cluster of cases of inflammatory syndrome in a short time and evidence that it’s in relation to COVID-19 “suggests that it is something new.”

This new syndrome has some overlap of symptoms with Kawasaki, in that many of the children being treated have had a fever, rash and redness of the eyes.

A high proportion also seem to have gastrointestinal effects, whether vomiting, abdominal pain or stomach ache or diarrhea, Fennelly said, and both do involve an inflammation of blood vessels.

Respiratory symptoms were reported in "less than half" of the patients in New York, according to the same New York health department update, which also noted the majority of patients who have presented with the syndrome have tested positive for either COVID-19 or corresponding antibodies.

So, what should a concerned parent do?

For any child with a fever, if there's also a rash and abdominal pain, immediately contact your pediatrician, Fennelly said. He said depending on the circumstances, they might suggest an in-person visit, or a telehealth session to evaluate the symptoms.

He said just as there is overlap on symptoms between Kawasaki disease and this multi-system inflammatory syndrome, there is an overlap of the therapies used to treat them.

At Thursday's state briefing, when asked about the syndrome, Department of Health Medical Director Edward Lifshitz said that the public should be aware that "this is a very rare disease and we're still learning about how it's associated with COVID."

Lifshitz said out of about 130,000 confirmed cases of COVID-19 in the state, only about 2% are in the pediatric population, which indicates to him that kids are not getting sick enough to be tested to be confirmed.

So, Lifshitz said, the very large majority of children either don't get sick at all or do so, minimally.

He said clinicians should know this inflammatory syndrome "is something that can happen or appears that it can happen" and something that needs to be acted on rapidly, concluding "It's rare, but it needs to be kept in mind."

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