Kawasaki disease is a rare condition in children that involves inflammation of the blood vessels. The condition is usually accompanied by a fever that lasts at least 5 days. Other classic symptoms may include red eyes, lips, and mouth; rash; swollen and red hands and feet; and swollen lymph nodes.

Kawasaki disease occurs most frequently in Japan, where the disease was first discovered, but it occurs in all ethnicities. In the United States, where Kawasaki disease is the leading cause of acquired heart disease in children, over 4,000 children develop it each year. 80% of patients are younger than 5 years of age.

Kawasaki disease is a poorly understood illness. The cause has not been determined. It may be an autoimmune disorder precipitated by unknown outside factors. The disorder affects the mucus membranes, lymph nodes, walls of the blood vessels, and the heart.

The heart's involvement and complications are, by far, the most important aspect of the disease. Kawasaki disease can cause inflammation of blood vessels in the coronary arteries, which can lead to aneurysms. (An aneurysm is a weakened area of blood vessel that balloons out.) Such aneurysms can lead to heart attack, even in young children (rarely).

Kawasaki disease often begins with a high and persistent fever greater than 102°F, often as high as 104°F. A persistent fever lasting at least five days is considered a hallmark sign. The fever may persist steadily for up to two weeks and is not very responsive to normal doses of acetaminophen or ibuprofen.

Other symptoms often include:

• Extremely bloodshot or red eyes (without pus or drainage)
• Bright red, chapped, or cracked lips
• Red mucous membranes in the mouth
• Strawberry tongue, white coating on the tongue, or prominent red bumps on the back of the tongue
• Red palms of the hands and the soles of the feet
• Swollen hands and feet
• Skin rashes, NOT blister-like, on the trunk
• Peeling skin in the genital area, hands, and feet (especially around the nails, palms, and soles)
• Swollen lymph nodes (frequently only one lymph node is swollen), particularly in the neck area.
• Joint pain and swelling, frequently symmetrical

There are no tests that specifically diagnose Kawasaki disease. The diagnosis is usually made based on the patient having most of the classic symptoms.

However, some children may have a fever lasting more than 5 days, but few of the other classic symptoms of the disease. Therefore, all children with fever lasting more than 5 days should be evaluated, with Kawasaki disease considered as a possibility. (The American Heart Association released guidelines for this assessment in the October 26, 2004 issue of Circulation.) Early treatment is essential for those who do have the disease.

The following tests may be performed:

• Complete blood count
• ESR
• Electrocardiogram
• Echocardiogram
• Chest x-ray
• Urinalysis - may show pus in the urine or protein in the urine

Procedures such as ECG and echocardiography may reveal signs of myocarditis, pericarditis, arthritis, aseptic meningitis, and inflammation of the coronary arteries.

Children with Kawasaki disease are hospitalized and care usually delivered by both pediatric cardiology and infectious disease specialists, although no infectious agent has been discovered. Treatment must be started as soon as the diagnosis is made to prevent damage to the coronary arteries and heart.

Intravenous gamma globulin is the standard treatment for Kawasaki disease and is administered in high doses. The child's condition usually greatly improves within 24 hours of treatment with IV gamma globulin.

Aspirin is often given in combination with the IV gamma globulin as part of the treatment plan.

With early recognition and treatment, full recovery can be expected. However, 2% of patients die from complications of coronary blood vessel inflammation. Patients who have had Kawasaki disease should have an echocardiogram every 1-2 years to screen for heart problems.

Complications involving the heart, including vessel inflammation and aneurysm, can cause a heart attack at a young age or later in life. The American Heart Association's October 2004 guidelines provide details on life-long followup.

Call your health care provider if symptoms of Kawasaki disease develop. A persistent high grade fever that is unresponsive to acetaminophen or ibuprofen and lasts more than 24 hours should be evaluated by a physician.

There are no known measures that will prevent this disorder.