In what is now thought to be the first reported case of its kind, an infant with Kawasaki disease, a rare inflammatory disease affecting coronary arteries in children, also tested positive in March for COVID-19 — suggesting a possible connection between the two illnesses, Stanford Children's Health doctors have reported.
Now, other medical experts in the country are finding a related and similar disease is emerging in children, despite the fact that most children with COVID-19 are generally asymptomatic or have mild to moderate symptoms.
Physicians at Lucile Packard Children's Hospital Stanford reported the case of a 6-month-old girl who was initially taken to pediatric urgent care in March after having one day of fever, fussiness and refusing to eat. She did not have symptoms of a respiratory infection, and laboratory tests ruled out influenza. She was diagnosed with an unspecified viral infection and sent home, according to the physicians' April 6 peer-reviewed, pre-publication version of an article found in American Academy of Pediatrics' journal Hospital Pediatrics.
On the second day, she developed a blotchy rash. By the fourth day, her parents returned to urgent care. She had a 101-degree fever, a heartbeat of 200 beats per minute and abnormally rapid breathing. One lung showed some congestion.
The infant was irritable, had conjunctivitis and dry, cracked lips. Admitted into the hospital, by day five, she had raised swellings on her tongue, a body rash with raised bumps, and swollen hands and lower extremities — classic symptoms of Kawasaki disease, according to the report's authors.
Doctors treated her intravenously with immunoglobulin and high doses of aspirin to help calm her body's reaction and reduce inflammation. She was about to be released from the hospital when her COVID-19 test came back positive, prompting her physicians to suspect there might be a connection, said Dr. Roshni Mathew, associate medical director of infection prevention and control at Lucile Packard Children's Hospital and an author of the report.
Mathew and the report's other authors warned physicians to be on the lookout for similar cases of Kawasaki disease in COVID-19 pediatric patients or those who have recovered from the coronavirus.
Then on April 27, the National Health Service England issued an alert regarding a severe inflammatory syndrome similar to Kawasaki disease, which seemed linked to COVID-19 and was afflicting children.
Kawasaki disease can cause inflammation in blood vessels and abnormal dilation of arteries that supply blood to the heart, Mathew said. The cause of Kawasaki isn't known, despite decades of study, but there is evidence that it is caused by a hyperinflammatory response to viruses, she said.
It has been associated with other viruses, including adenoviruses, enteroviruses, rhinoviruses, and other coronaviruses, but it was not associated with COVID-19 patients prior to the Stanford report.
About 50% of its cases occur in children younger than 2 years of age; 80% of cases are in those younger than 5 years old.
Kawasaki disease or a deadlier, emerging syndrome?
Health experts are calling the Kawasaki-like disease "pediatric inflammatory multisystem syndrome." Rather than affecting only the blood vessels in the heart, the syndrome is causing inflammation in multiple organs and systems. It also has led to three deaths in New York, with two others under investigation.
The New York City Health Department issued a health alert on May 5 announcing 15 cases of pediatric inflammatory multisystem syndrome. The next day, New York State issued a health advisory after it announced the number of syndrome cases statewide had increased to 64. By Monday, May 11, the state had 93 cases.
New York Gov. Andrew Cuomo alerted other U.S. governors about the syndrome. New Jersey also had eight cases and Connecticut had three as of Monday, their governors have said.
Like Kawasaki, pediatric inflammatory syndrome can cause cardiac inflammation. It can also cause some symptoms found in toxic shock syndrome. Symptoms include sepsis, shock and dysfunction of the heart, kidneys, gastrointestinal tract, lungs and brain, and other crossover symptoms with the other two diseases, according to health authorities.
The new diagnosis is causing some doctors to change their findings from Kawasaki to pediatric inflammatory multisystem syndrome. Doctors at Children's Hospital Los Angeles on May 8 said in a statement they had three cases after changing their diagnoses from Kawasaki. They started noticing more children were being diagnosed with Kawasaki disease in April than the previous two Aprils, prompting suspicions of a link to COVID-19, they said. The hospital began testing patients who were diagnosed with Kawasaki disease in recent months to see if they had antibodies showing past COVID-19 infection.
"Each child was initially believed to have Kawasaki disease and received treatment from the hospital's team of experts in infectious diseases and Kawasaki disease. Positive antibody testing for each of the patients, combined with a set of symptoms consistent with other patients around the world and additional negative viral testing has led the CHLA team to diagnose these patients with PIMS," the hospital said. Neither the syndrome nor Kawasaki disease is contagious, they noted.
Stanford hasn't changed its diagnosis of the March case. Mathew said the symptoms were "classic" Kawasaki disease. It's also hard to say if the Packard case of Kawasaki disease is tied to COVID-19 or if its appearance was coincidental, she said.
The girl's older brother had a virus three weeks prior but neither he nor the parents tested positive for COVID-19. Some cases reported in the United Kingdom also did not test positive for the coronavirus, authorities said in their alert.
"People are actively looking to see if this year there are markedly more cases," Mathew said. "If there is truly more than baseline, we will know if there is truly a connection."
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