Kawasaki Disease

Topic Overview

What is Kawasaki disease?

Kawasaki disease is a rare childhood illness that affects the blood vessels. The symptoms can be severe for several days and can look scary to parents. This disease tends to be severe for several days, but then most children return to normal activities.

Kawasaki disease can harm the coronary arteries, which carry blood to the heart. Most children who are treated recover from the disease without long-term problems. Your doctor will watch your child for heart problems for a few weeks to a few months after treatment.

The disease is most common in children ages 1 to 2 years and is less common in children older than age 8. It does not spread from child to child (is not contagious).

What causes Kawasaki disease?

Experts don't know what causes the disease. It may be caused by infection from a virus or bacteria. The disease happens most often in the late winter and early spring.

What are the symptoms?

Symptoms of Kawasaki disease include:

• A fever lasting at least 5 days.
• Red eyes.
• A body rash.
• Swollen, red lips and tongue.
• Swollen, red feet and hands.
• Swollen lymph nodes in the neck.

Get medical help right away if your child has symptoms of Kawasaki disease. Early diagnosis and treatment can often prevent future heart problems.

How is Kawasaki disease diagnosed?

Kawasaki disease can be hard to diagnose because there is not a test for it. Your doctor may diagnose Kawasaki disease if both of these things are true:

• Your child has a fever that lasts at least 5 days.
• Your child has four of the other five symptoms listed above.

After your child gets better, he or she will need checkups to watch for heart problems.

How is it treated?

Treatment for Kawasaki disease starts in the hospital. It may include:

• Immunoglobulin (IVIG) medicine. This is given through a vein (intravenous, or IV) to reduce inflammation of the blood vessels.
• Aspirin to help pain and fever and to lower the risk of blood clots.

Aspirin therapy is often continued at home. Because of the risk of Reye syndrome, do not give aspirin to your child without talking to your doctor. If your child is exposed to or develops chickenpox or flu (influenza) while taking aspirin, talk with your doctor right away.

How serious is Kawasaki disease?

Most children with Kawasaki disease get better and have no long-term problems. Treatment is important because it shortens the illness and reduces the chances of problems.

Some children who are not treated will have damage to the coronary arteries. An artery may get too large and form an aneurysm. Or the arteries may narrow or develop blood clots. A child who has damaged coronary arteries may be more likely to have a heart attack as a young adult.

Frequently Asked Questions

Symptoms

The early symptoms of Kawasaki disease are similar to many other infections or allergic reactions.

The first symptom usually is a sudden, high fever that may be 104°F (40°C) or higher. Unlike fever caused by common viruses, the fever from Kawasaki disease can last more than 10 days if the disease is not treated.

Other symptoms that can occur along with fever include:

• Red, bloodshot eyes, usually without pus or discharge.
• A red body rash that varies in size, shape, and consistency. The rash rarely blisters and is usually most obvious in the torso or groin area.
• Red, swollen, cracked lips and a red ("strawberry") tongue and lining of the mouth.
• Firm, swollen hands and feet with shiny red palms and soles. The skin begins to shed and peel between 1 and 3 weeks after the fever starts. Peeling starts under the fingernails and toenails and slowly spreads to the palms and soles.
• Swelling of lymph nodes on one side of the neck. Swelling very rarely occurs on both sides of the neck.

Other symptoms may include:

• Irritability and tiredness.
• Joint swelling and pain. The pain sometimes is very severe. A child may refuse to move or put weight on his or her hands and feet.
• Abdominal pain, vomiting, and diarrhea.
• A rapid heart rate or changes in heart rhythm from heart inflammation.

Other conditions with symptoms similar to Kawasaki disease include measles, Epstein-Barr infections, scarlet fever, drug reactions, toxic shock syndrome, and juvenile rheumatoid arthritis. It is important for a child with symptoms to see a doctor for diagnosis and proper treatment.

If your child has symptoms of Kawasaki disease, seek medical attention immediately. Early diagnosis and treatment often prevent life-threatening problems.

Exams and Tests

Initial diagnosis

There is no specific test for Kawasaki disease, so diagnosing the disease can be difficult. Doctors use specific criteria developed by the American Heart Association (AHA) to diagnose Kawasaki disease.

Routine lab tests may be done to rule out Kawasaki disease. These tests may reveal another condition, usually a bacterial or viral infection. The most common tests are:

• A complete blood count. This test counts the number of red blood cells and white blood cells.
• Urinalysis. This test can help determine whether illness is present.
• Sedimentation rate or C-reactive protein (CRP). These blood tests can help find out if inflammation exists.

If your doctor suspects Kawasaki disease, he or she may order an echocardiogram to check for heart problems.

Follow-up tests

Children who have had Kawasaki disease need to have a follow-up exam at 2 to 3 weeks and at 2 to 3 months after the initial disease. Tests done during the exam include:

• Blood tests to monitor how well the medicines are working.
• An echocardiogram to check heart functioning and to detect aneurysms of the coronary arteries.

In rare cases, other tests are used to see whether there is damage to the heart.

• An electrocardiogram (ECG or EKG) may be used to identify problems with the heart's electrical function.
• A chest X-ray helps check heart size and the chance of heart failure.
• A coronary angiogram may be done if the echocardiogram reveals problems with the coronary arteries.
• A stress test may be done to see how the heart responds to exercise.

Treatment Overview

Kawasaki disease is treated with medicines. Long-term care may be needed and might include continued medicine, limited physical activity, and repeated testing.

Early treatment of Kawasaki disease prevents most blood vessel and heart damage. If children with Kawasaki disease are hospitalized and treated within 10 days after the first signs of illness, the risk of heart disease and aneurysms greatly decreases.

For the best treatment, have your child’s pediatrician work with a pediatric cardiologist.

Medicines

Medicines used to treat Kawasaki disease include intravenous immunoglobulin, aspirin, and possibly anticoagulants.

Intravenous immunoglobulin (IVIG). Intravenous immunoglobulin (IVIG) is used to reduce inflammation of blood vessels. IVIG usually is given in 1 dose through a vein, over 8 to 12 hours. The treatment usually requires that the child stay in the hospital for at least 24 hours. After IVIG treatment, the illness usually improves very quickly. IVIG works best if it is given before the tenth day of fever. Sometimes a second dose of IVIG is needed because the first dose did not reduce the fever and inflammation.

Aspirin therapy.At first, high-dose aspirin is used to relieve inflammation and fever. If there are no complications, smaller daily doses are then given for 2 to 3 months to lower the risk of dangerous blood clots. Because of the risk of Reye syndrome, aspirin should be given only under the guidance of a doctor. If the child is exposed to or develops chickenpox or flu (influenza) while taking aspirin, talk with a doctor right away. For more information, see the topic Reye Syndrome.

Anticoagulants. Anticoagulants may be used if the child has an aneurysm. Anticoagulants help prevent new blood clots.

After initial treatment, the child's fever and inflammation should improve, but the child may still be irritable, not have an appetite, and not be very active. Also, the child’s fingers and toes may peel or his or her fingernails may get deep lines in them (Beau's lines). It may be several weeks before the child feels completely well.

Follow-up treatment

Your child's doctor may do echocardiograms to check for aneurysms. This test may be done at 2 to 3 weeks and at 6 to 8 weeks after the illness. It may also be done at later times.

If echocardiogram results from follow-up exams are normal, your child probably will not need further care.

But if these test results show changes in the coronary arteries, long-term care of the disease may be needed. This care may include:

• Repeated exams and tests every year or every 3 to 5 years, depending on the child's risk for heart problems.
• Continued low-dose aspirin therapy, sometimes combined with other medicines that lower the risk of blood clots.
• Limited physical activity.
• Annual flu shot (influenza vaccine (What is a PDF document?)).

What to think about

Treatment with immunoglobulin (IVIG) sometimes interferes with the effectiveness of immunizations against measles, mumps, rubella (MMR) (What is a PDF document?), and chickenpox (What is a PDF document?). For children who have received IVIG treatment, the MMR and chickenpox immunizations should be postponed for 11 months.

Home Treatment

Home treatment in general is not appropriate for children with Kawasaki disease. Treatment starts in the hospital and then is followed by long-term aspirin therapy, which may be given at home.

Seek emergency care if your child has been diagnosed with heart problems (coronary artery problems) and has chest pain, is short of breath, faints, or has a lack of energy.

Other Places To Get Help

Organizations

Related Information

• Fever, Age 3 and Younger
• Fever, Age 4 and Older
• Rash, Age 11 and Younger
• Reye Syndrome

References

Other Works Consulted

• Langford CA, Fauci AS (2008). Kawasaki disease section of The vasculitis syndromes. In AS Fauci et al., eds., Harrison's Principles of Internal Medicine, 17th ed., vol. 2, p. 2130. New York: McGraw-Hill.
• Mandell BF (2006). Kawasaki disease section of Systemic vasculitis syndromes. In DC Dale, DD Federman, eds., ACP Medicine, section 15, chap. 8. New York: WebMD.
• Newburger JW, et al. (2006). Kawasaki disease. In FD Burg et al., eds., Current Pediatric Therapy, 18th ed., pp. 497–503. Philadelphia: Saunders.
• Oates-Whitehead RM, et al. (2003). Intravenous immunoglobulin for the treatment of Kawasaki disease in children. Cochrane Database of Systematic Reviews(4). Oxford: Update Software.
• Rowley AH, Shulman ST (2007). Kawasaki disease. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 18th ed., pp. 1036–1042. Philadelphia: Saunders Elsevier.
• Shulman ST (2004). Kawasaki disease. In R Feigin et al., eds., Textbook of Pediatric Infectious Diseases, 5th ed., vol. 2, pp. 1055–1074. Philadelphia: Saunders.
• Takahashi M, Newburger JW (2008). Kawasaki disease (mucocutaneous lymph node syndrome). In HD Allen et al., eds., Moss and Adams' Heart Disease in Infants, Children, and Adolescents, Including the Fetus and Young Adult, 7th ed., vol. 2, pp. 1242–1256. Philadelphia: Lippincott Williams and Wilkins.

Credits