What Is Kawasaki Disease?

Kawasaki disease is an illness that causes inflammation (swelling and redness) in blood vessels throughout the body. It happens in three phases, and a lasting fever usually is the first sign.

The condition most often affects kids younger than 5 years old. When symptoms are noticed early and treated, kids with Kawasaki disease begin to feel better within a few days.

What Are the Signs & Symptoms of Kawasaki Disease?

Kawasaki disease has telltale symptoms and signs that appear in phases. The first phase, which can last for up to 2 weeks, usually involves a fever that lasts for at least 5 days.

Other symptoms include:

• red ("bloodshot") eyes
• a pink rash on the back, belly, arms, legs, and genital area
• red, dry, cracked lips
• a "strawberry" tongue (white coating with red bumps on the tongue)
• a sore throat
• swollen palms of the hands and soles of the feet with a purple-red color
• swollen lymph glands in the neck

The second phase usually begins 2 weeks after the fever started. Symptoms can include:

• peeling skin on the hands and feet
• joint pain
• diarrhea
• vomiting
• belly pain

What Problems Can Happen?

Doctors can treat the symptoms of Kawasaki disease when it's caught early. Most kids will feel better within a few days of starting treatment.

If the condition isn't found until later, patients can have serious complications that affect the heart, such as:

• an aneurysm (a bulge in the wall) of the coronary arteries, which supply blood to the heart
• inflammation of the heart muscle, lining, valves, and the outer membrane around the heart
• arrhythmias, which are changes in the normal pattern of the heartbeat
• problems with some heart valves

What Causes Kawasaki Disease?

Doctors don't know what causes Kawasaki disease. They believe it doesn't spread from person to person. It's most common among children of Japanese and Korean descent, but can affect any child.

How Is Kawasaki Disease Diagnosed?

Kawasaki disease symptoms can look similar to those of other childhood viral and bacterial illnesses. Doctors usually diagnose it by asking about the symptoms (such as a long-lasting fever) and doing an exam.

If Kawasaki disease looks likely, the doctor:

• will order tests to check the heart, such as an echocardiogram
• might test blood and urine (pee) samples to rule out other conditions, such as scarlet fever, measles, Rocky Mountain spotted fever, or juvenile rheumatoid arthritis

How Is Kawasaki Disease Treated?

Doctors usually treat kids with Kawasaki disease by giving them:

• intravenous (IV) dose of immune globulin (IVIG): These antibodies (proteins) help fight infections. IVIG treatment also lowers the risk of coronary artery aneurysms. IVIG is given once.
• high-dose aspirin given by mouth to treat inflammation. Patients take aspirin until blood tests show that the inflammation has improved.

Treatment begins as soon as possible. In some children, IVIG may not work and doctors give steroids instead. Steroids can help prevent coronary aneurysms.

It's very important for children on high-dose aspirin to get the annual flu vaccine to help prevent this viral illness. That's because there's a small risk of a rare condition called Reye syndrome in children who take aspirin during a viral illness.

Most children with Kawasaki disease start to get much better after a single treatment with immune globulin, though sometimes more doses are needed.

What Else Should I Know?

Most kids with Kawasaki disease recover completely, especially when they are diagnosed and treated early. Some, especially those who develop heart problems from Kawasaki disease, might need more testing and to see a cardiologist (a doctor who specializes in conditions that affect the heart).