What Is Kawasaki Disease, The Rare Illness That Might Impact Kids With COVID-19?

Fifteen children in New York City have been hospitalised with symptoms consistent with Kawasaki disease, a rare condition that causes swelling in the arteries. Experts think the rash of cases, which have been reported in kids ages 2 to 15, may be linked to COVID-19. In the United Kingdom, cases of Kawasaki have been confirmed in children with coronavirus, reports The Cut.

On 4th May, Demetre Daskalakis, MD, deputy commissioner of The New York City Health Department's Division of Disease Control, put out a public letter to his colleagues warning of the illnesses. "A paediatric multi-system inflammatory syndrome, recently reported by authorities in the United Kingdom, is also being observed among children and young adults in New York City and elsewhere in the United States," Dr Daskalakis wrote. 

But what, exactly, is Kawasaki disease, and how is it linked to the SARS-CoV-2 outbreak? We asked Robert Segal, MD, a physician at Manhattan Cardiology and the president of Lab Finder, to help break it down. 

“It’s a rare disorder that you’ll find in about 20 out of every 100,000 or so paediatric cases,” Dr Segal says. “It causes inflammation of the blood vessels, something we call vasculitis... It’ll impact multiple organs: the skin, the eyes, the heart, the kidneys, the lymph nodes. It mainly affects young children, and it usually starts out with a persistent fever of 101 to 104 [degrees] and a funky red rash.” 

There is no known cause. “It could be genetic, it could be from a virus or another bacteria,” Dr Segal says. “It’s one of those insidious diseases. There seems to be some predisposition, and it can be passed through generations, but there’s no inheritance pattern.” 

Researchers don’t believe it can be transmitted from one person to another, so it won’t necessarily spread like wildfire — or like COVID-19. 

Aside from the fever and the rash, Dr Segal says initial symptoms may include red eyes, due to blood vessel inflammation in the whites of the eyeballs. Other warning signs: red lips, changes in lymph nodes, and a “strawberry-coloured tongue that looks swollen and bumpy,” he notes.

In the second phase of the illness, the skin on patients' hands and feet might peel, and they may experience joint pain, diarrhoea, and vomiting, according to Mayo Clinic. 

“There’s no cure. It usually resolves in a month or two,” Dr Segal says, adding, "There are cardiac manifestations we see in adults when they've had it as kids." The blood vessel inflammation weakens some arteries, he explains. Later, the arteries could bulge, leading to an aneurysm. 

Other complications can include inflammation of the heart muscle and heart valve problems, reports the Mayo Clinic.

Although Kawasaki can’t be officially “cured,” it’s generally treatable with aspirin or similar fever-reducing drugs. Sometimes, intravenous immunoglobulin is needed to bring down inflammation, Dr Segal says.

Dr Daskalakis emphasised in his letter that early diagnosis and treatment of patients who have some or all of the symptoms of Kawasaki disease should be a priority for doctors. Catching it early may help prevent the organ damage and other long-term complications that can sometimes arise.

“That’s the million dollar question,” Dr Segal says. From what officials understand, “this is a rare complication in the paediatric population that they believe is related to COVID-19,” Howard A. Zucker, MD, the New York State health commissioner, told The New York Times.

How exactly it could be related to coronavirus is still unclear. Both Kawasaki and the coronavirus cause inflammation of multiple systems within the body, Dr Segal notes. Forbes notes that some researchers believe that Kawasaki is triggered by a viral infection, even a common cold, so it's possible that the patients are first contracting COVID-19 and then developing Kawasaki disease. But at this point, that's speculation.

“Even though the relationship of this syndrome to COVID-19 is not yet defined, and not all of these cases have tested positive for COVID-19 by either DNA test or serology, the clinical nature of this virus is such that we are asking all providers to contact us immediately if they see patients who meet the criteria we’ve outlined,” New York City’s health commissioner Oxiris Barbot, MD, said in a statement she released.

She told parents: “if your child has symptoms like fever, rash, abdominal pain, or vomiting, call your doctor right away.”

Although scientists initially believed that children were less at risk of severe complications from COVID-19, Dr Segal says he’d encourage kids to stick to the same safety measures as adults, such as social distancing and hand washing.

“The mortality rate might be lower in children, but I wouldn’t say it spares them,” Dr Segal says. “It might be milder in children, but there have been cases of kids dying of COVID… They call it the novel coronavirus for a reason — it’s novel. No one knows much about it, and it’s still a confounding, puzzling virus that doesn’t just affect adults.”