According to the Centers for Disease Control and Prevention (CDC), Kawasaki disease, or Kawasaki syndrome, is an inflammation of the blood vessels that is most common in children under 5 years of age. While much isn’t known about its causes, overall, the disease is very rare and with treatment, most kids with the disease can make a full recovery.
We spoke with Nathan Price, MD, a pediatric infectious disease specialist with Banner Children's, to learn more about Kawasaki disease.
What causes Kawasaki disease?
“We don’t exactly know the causes of Kawasaki disease, but the fact that it is more common in certain seasons, can happen in epidemic waves, can sometimes occur in multiple family members, tends to affect younger children and is more common in certain ethnicities suggests that there is a common infection (likely a virus) that causes a certain type of inflammation in people with certain genetics,” Dr. Price said.
While its causes aren’t clear, the disease is thought to be a reaction to the body’s immune system and there are some factors that may increase your child’s risk. These include:
- Age: Children under 5 years old
- Sex: Boys are more affected than girls
- Ethnicity: There’s been higher rates in those of Asian descent, even those who live in non-Asian countries
“The fact that older children and adults don't usually get Kawasaki disease suggests that they already got the infection and are now immune to it, and won't get the inflammatory response when exposed again to the virus (or whatever infectious agent there is that sets it off),” Dr. Price said.
What are the symptoms of Kawasaki disease?
One of the earliest signs to look out for is a fever that goes on for at least 5 days. Other signs and symptoms of Kawasaki disease may include:
- Red, bloodshot eyes
- Red rash
- Swollen, painful hands and feet
- Red, cracked lips and red, swollen tongue
- Swollen lymph nodes in the neck
- Irritability and exhaustion in children
How is Kawasaki disease diagnosed?
Unfortunately, there is no test at this time to diagnose Kawasaki disease. Instead, your child’s doctor will make a diagnosis by seeing if the patient has enough of the signs and symptoms to call it Kawasaki disease. If it’s suspected, they’ll admit your child into the hospital.
While in the hospital, the doctor may order a series of tests, including an electrocardiogram and/or echocardiogram to monitor the heart and blood vessels, as well as, blood and urine tests to look for abnormalities in your child’s blood cells and proteins that may signal inflammation.
“Inflammation can cause particular harm to the heart,” Dr. Price said. “About 25% of children who don’t get treatment can have swelling of the arteries that feed the heart. In some of these children, they can get blood clots in the swollen arteries that can lead to heart attack and death. To reduce the risk, treatment should be started within 10 days after the onset of symptoms.”
How is Kawasaki disease treated?
Children diagnosed with Kawasaki disease are treated with a gamma globulin, also called intravenous immunoglobulin (IVIG), which are general antibodies from blood donors that are used to help decrease inflammation and make the risk of coronary artery aneurysm much lower (around 4%). A small percentage of children will need an additional IVIG treatment if they don’t respond to the first dose.
What is the long-term outlook for Kawasaki disease?
“Other than the possible long-term heart problems, there doesn’t seem to be any common long-term problems with the disease,” Dr. Price said. “These lasting heart conditions are very rare and most cardiovascular health returns to normal within a few months.”
Talk to your doctor.
If your child is exhibiting the symptoms of Kawasaki disease and has had a fever for at least 5 days, contact their pediatrician right away.
“While your child could simply be fighting something benign like a cold, it never hurts to get an informed opinion from their doctor,” Dr. Price said. “Go with your gut.”