Skip to main content

Health library

What is Kawasaki disease?

Kawasaki disease isn't very common, but without treatment it can be very dangerous. If your child has the symptoms, call your doctor immediately.

Kawasaki disease is a rare illness that can cause severe heart damage. The disease is more common in Japan than any other country, according to the American Heart Association (AHA).

In the United States, Kawasaki disease is most common in children of Asian descent, though it can occur in any racial or ethnic group. It occurs nearly twice as often in boys as it does in girls, almost always before age 5.

Dangerous inflammation

Kawasaki disease causes inflammation of blood vessels throughout the body, sometimes including the heart. The inflammation weakens the vessel walls and can lead to balloon-like swellings called aneurysms.

Infants younger than a year old are at the greatest risk for heart problems from Kawasaki disease, according to the AHA.

The cause of Kawasaki disease isn't known, though some researchers suspect that it is a reaction by the body's immune system. Outbreaks sometimes occur in the winter and spring, but the disease isn't believed to be contagious. It doesn't spread among children in child care centers, and it's rare for two children in the same household to get the disease, according to the American Academy of Pediatrics (AAP).

The symptoms

According to the AHA, to be diagnosed with Kawasaki disease, a patient must have a fever for at least five days and have at least four of the following symptoms:

  • Bloodshot eyes.
  • Inflammation of the mouth, lips and throat.
  • Swollen lymph glands in the neck.
  • Redness and swelling on the soles of the feet and the palms at the beginning of illness. Peeling of the skin on the fingers and toes in the second and third weeks.
  • A rash over the torso and extremities.

Diagnosis and treatment

A doctor who suspects the disease may admit a child to the hospital immediately.

There's no single test for Kawasaki disease, so a diagnosis is made by noting symptoms and ruling out other possible diseases. An imaging test may be done to check for damage to the heart and blood vessels.

Most children with Kawasaki disease are treated with immunoglobulin, a blood product with proteins in it that fight infection. This treatment reduces the risk that the heart muscle will become inflamed or that blood vessels will weaken and swell.

A doctor may also recommend aspirin to reduce the risk of a dangerous blood clot forming in a damaged blood vessel. Blood clots can break loose from the blood vessel wall and travel to the heart, lungs or brain, cutting off the blood supply. Parents should always consult a doctor before giving aspirin to a child, according to the AAP. Giving aspirin to a child who has a fever may increase the risk for Reye's syndrome.

A generally good prognosis

With treatment, most children with Kawasaki disease who don’t develop aneurysms recover completely and return to normal activity within two months. However, kids who develop aneurysms should have long-term, possibly lifelong, follow-up.  

Reviewed 3/4/2022

Related stories