In a previous report from Science Times, New York has suddenly experienced a surge in Kawasaki-like disease cases in children aged 2 to 15. Doctors were unsure at that time whether the coronavirus infection causes this new inflammatory disease.

But recently, experts have already confirmed that indeed, coronavirus has been causing the Kawasaki-like disease on children. They first found evidence in a study of eight children admitted to Birmingham hospital.

Symptoms of the inflammatory disease emerged several weeks after they were infected with the SARS-CoV-2. Surprisingly, children did not test positive using the lab-based PCR tests commonly used to spot COVID-19.

But a custom-built antibody test revealed that the young patients produced antibodies to fight off the pathogen. According to the doctor who was treating the children, antibody tests are the only way to accurately identify the presence of the virus in children with the inflammatory disease, which could be deadly.

It is still a mystery why the syndrome develops weeks after infection. The scientists believe that it could be an overreaction from the body's immune system. Moreover, a similar syndrome is also observed among adult patients.

The Kawasaki-like syndrome in children has been tentatively called PIIMS-TS, which stands for 'Pediatric Inflammatory Multisystem Syndrome Temporarily associated with SARS-CoV-2. It was disagreed by some experts saying that it is not 'temporally associated' with the pandemic, but instead, it is 'triggered by SARS-CoV-2.

Kawasaki-like Syndrome is Caused by the Coronavirus

Dr. Alex Richter and Professor Adam Cunningham of the University of Birmingham conducted a study together with other researchers on eight young patients admitted to the hospital between April 18 and May 8.

They first tested them for coronavirus, but it came back negative, the researchers told MailOnline. Out of eight children, seven of them displayed hyper inflammation and Kawasaki disease, while one young patient has hyper inflammation and toxic shock syndrome. Six of them were brought to the pediatric intensive care unit and eventually showed positive signs after treatment.

Due to the reports that it could be related to coronavirus, they took blood samples from all eight children for analysis. Then, they develop a customized antibody test. The researchers saw that some antibodies in the blood of the children bound to the spike of the coronavirus.

But why did they test negative with the PCR? According to the scientists, for the PCR to detect the virus, it should be able to detect IgM that indicates a recent infection. But the children did not have those but only tested positive with IgG and IgA antibodies, which only shows older infections.

This result indicates that a high level of IgG compared to IgM could mean that infection had happened weeks before symptoms were observed.

Can Only be Diagnosed with Antibody Tests

The antibody test used in detecting the infection on young patients is conducted inside a laboratory and is not a portable test. Since it is a customized antibody test, it is not the same as the commonly used antibody test approved by the government.

According to the researchers, their findings suggest that children cannot be diagnosed using only the PCR. This means that the disease developed after the kids have already cleared the virus, and so serology may be more useful in diagnosing kids.

Most importantly, their findings inform that sometime in the past, the children caught the virus. This information is helpful for the physician who will be treating them to provide an accurate treatment.