A small but rising number of children are becoming ill with a rare syndrome that could be linked to coronavirus, with reported cases showing symptoms of abdominal pain, gastrointestinal symptoms and cardiac inflammation, U.K. health care bosses and pediatrics specialists have warned.

On Sunday, the Paediatric Intensive Care Society U.K. (PICS) tweeted an "urgent alert" from the National Health Service England about a small rise in the number of cases of critically ill children presenting "overlapping features of toxic shock syndrome and atypical Kawasaki disease with blood parameters" -- with some of the children testing positive for Covid-19.

The urgent alert, sent to U.K. general practitioners by National Health Service (NHS) England warned that over the last three weeks, "there has been an apparent rise in the number of children of all ages presenting with a multisystem inflammatory state requiring intensive care across London and also in other regions of the U.K.," the Health Service Journal first reported Monday.

The alert added: "There is a growing concern that a [covid-19] related inflammatory syndrome is emerging in children in the U.K., or that there may be another, as yet unidentified, infectious pathogen associated with these cases," HSJ added.

In a statement sent over the weekend to medical professionals who look after critically ill children, PICS said "the cases have in common overlapping features of toxic shock syndrome and atypical Kawasaki disease with blood parameters consistent with severe Covid-19 in children. Abdominal pain and gastrointestinal symptoms have been a common feature as has cardiac inflammation."

Kawasaki disease, also known as Kawasaki syndrome, is a rare childhood illness that causes the walls of the blood vessels in the body to become inflamed.

The group said that while there had been "very few cases" of critically unwell children with Covid-19 admitted to pediatric intensive care units in the U.K. and around the world, they were aware of a "small number of children nationally" who fit the clinical picture described in the NHS alert.

There are still a lot of unknowns when it comes to Covid-19, but in a report released in April, the US Centers for Disease Control and Prevention said that children diagnosed with coronavirus in the United States typically have mild cases of the virus.

The number of Covid-19 cases among children remains small and while some children and infants have been sick with Covid-19, adults make up most of the known cases to date, according to the CDC.


Health care professionals have reassured parents that the risk of children becoming severely ill with the virus remains low.

"Thankfully Kawasaki-like diseases are very rare, as currently are serious complications in children related to Covid-19, but it is important that clinicians are made aware of any potential emerging links so that they are able to give children and young people the right care fast," Professor Simon Kenny, NHS national clinical director for children and young people said in a statement sent to CNN.

In response to the reports, Professor Russell Viner, president of the Royal College of Paediatrics and Child Health said that although a small number of children can become severely ill with Covid-19, it is "very rare," with evidence showing that children appear to be least affected by the virus.

"However our advice remains the same: parents should be reassured that children are unlikely to be seriously ill with Covid-19 but if they are concerned about their children's health for any reason, they should seek help from a health professional," Viner said.

Dr. Tina Tan, professor of pediatrics and infectious diseases at Northwestern University's Feinberg School of Medicine, said that the NHS England alert was important information to have here in the United States.

"I think it's really important that an alert like that goes out, not to alarm anybody but to have people be aware of the fact that this can happen. There have been an increased number of cases like this reported in Italy as well as Spain. Here in the US, I think we're just starting to see it," Tan told CNN Monday.

"Here in Chicago at Lurie Children's Hospital, we are just starting to see an increase in the number of older adolescents that are being hospitalized with fairly severe Covid disease that is requiring treatment," Tan said. "Here in Chicago, some of the kids have some of the underlying conditions that would predispose you to getting more severe Covid disease, such as obesity and hypertension."

Tan added that racial disparities are also emerging among Covid-19 cases in children.

"Out of Los Angeles they were reporting that younger African-Americans and Latinos were being affected by Covid more severely and actually being hospitalized," Tan said.