History of Kawasaki DiseaseKawasaki disease (KD) was first documented in the 1960s by Japanese pediatrician Tomisaku Kawasaki and was initially thought to be a benign illness. Soon after, the link to coronary artery disease was established. Since then, KD has become the leading cause of acquired heart disease among children in the US.
What Causes Kawasaki Disease?
Kawasaki disease is more prevalent in children of Asian and Pacific Island descent, but it can affect people of all ethnic and racial groups.
Kawasaki disease in children usually happens under age five,though older children can also be affected. The average age of children with KD is two years old. It occurs more commonly in boys than in girls.
Is Kawasaki Disease Contagious?
No, Kawasaki disease is not contagious.
Why is Kawasaki Disease a Concern?
In most cases, Kawasaki disease will go away on its own. Fever and various other symptoms can last anywhere from 5 days to 2 weeks, but eventually, the symptoms go away without any specific treatment. However, if the disease is left untreated, about 25% of those affected can develop complications with their heart.
The coronary arteries are the blood vessels that provide the heart muscle with an oxygen-rich blood supply. Kawasaki disease can weaken the wall of the coronary arteries, causing them to bulge or balloon out. This weakened area is called an aneurysm.
Blood clots can form in the ballooned area, potentially blocking the blood flow through the coronary artery. When this happens, the heart muscle will no longer receive an adequate supply of oxygen-rich (red) blood and can become damaged.
Kawasaki disease may also cause the heart muscle (myocardium), as well as the membrane covering the heart (pericardium) to become irritated and inflamed. Irregular heart rhythms and heart valve problems may also occur with Kawasaki disease.
In most cases, the effects on the heart caused by Kawasaki disease are temporary and resolve within 5 or 6 weeks. However, coronary artery problems may sometimes persist for a lifetime.
What are the symptoms of Kawasaki disease?The following are the most common symptoms of Kawasaki disease, though they do not have to all be present or present at the same time:
- Moderate-to-high fever (101.0° F to 104.0° F [38.3°C to 40.0°C]) that lasts for at least five days
- Swollen lymph nodes in the neck
- Bloodshot eyes (bilateral conjunctivitis)
- Dry, red, cracked lips or “strawberry tongue”
- Red, swollen palms of hands and soles of feet
- Peeling skin around the nail beds, hands or feet
How is Kawasaki disease diagnosed?There is no test to diagnose Kawasaki disease. Instead, your child’s healthcare provider will review medical history perform a physical exam and may opt for bloodwork or other studies to help determine a diagnosis. Several of the symptoms mentioned above must also be present for your child’s healthcare provider to consider Kawasaki disease. Kawasaki disease diagnostic tests may also include:
- Electrocardiogram (ECG). A test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage. Learn more about electrocardiograms.
- Echocardiogram (Echo). A procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves. Learn more about echocardiograms.
- X-ray. A diagnostic test, which uses invisible X-ray energy beams to produce images of internal tissues, bones, and organs onto film. Learn more about X-rays.
- Complete blood count (CBC). A measurement of size, number, and maturity of different blood cells in a specific volume of blood. The health care provider will look for an elevation in the numbers of white blood cells which normally multiply in the presence of infection and may notice elevated platelet levels with Kawasaki disease as well. Learn more about blood tests.
- Erythrocyte sedimentation rate (ESR or sed rate) and C-reactive protein (CRP). A nonspecific measurement of inflammation in the blood.
- Urinalysis. Testing of a urine sample for protein, red blood cells, white blood cells, or casts to indicate kidney disease associated with several rheumatic diseases.
How is Kawasaki disease treated?
Specific treatment for Kawasaki disease will be determined by your child’s health care provider based on several different criteria including age and severity of disease. Generally, treatment will include the use of Intravenous Immunoglobulin (IVIG) and aspirin.
Intravenous Immunoglobulin (IVIG), is a treatment that helps reduce fever and lower the risk of heart problems. After treatment, a child’s symptoms usually improve within 36 hours. If, after 36 hours, a child’s fever does not improve or returns, their doctor may opt for a second dose of IVIG or other medications such as Infliximab.
Aspirin is a medication that helps to decrease inflammation and prevent clot formation in the coronary arteries. It is continued for at least 6 weeks and sometimes longer depending on the coronary artery status after 6 weeks.
Kawasaki Disease Research
By coming to CHOC for your child’s care, you are choosing a hospital committed to staying at the forefront of medical research and providing the most advanced, effective treatments. Our team of world-renowned pediatricians and researchers is passionate about uncovering new insights into this complex and rare condition, with the goal of improving the outcomes for our patients.
CHOC participated in a recent study comparing the effectiveness and safety of Infliximab and a second infusion of intravenous immunoglobulin (IVIG) for patients who do not respond to initial IVIG treatment. The study found that Infliximab resulted in a shorter duration of fever, reduced need for additional therapy, less severe anemia, and shorter hospitalization compared to a second IVIG infusion. We are hopeful about the new insights this study has uncovered and look forward to being a part of continued advancements in treating Kawasaki disease.
What is the long-term outlook after having Kawasaki disease?
Most children will experience a full recovery after treatment for Kawasaki disease. Some heart problems may not be evident right away, so it is important to keep follow-up appointments with your child’s health care provider, even if your child is feeling well. At minimum, children with Kawasaki disease remain on a low dose of aspirin and get follow-up echocardiograms at two and six weeks after treatment. More frequent follow up may be necessary if abnormalities are noted on the initial echocardiograms. Your child’s medical team will work with you to make sure appropriate follow up is arranged and all your questions are answered before discharge.
Every child’s situation is unique, so it is important to speak with your child’s healthcare provider about their specific long-term outlook.