How Do You Get Kawasaki Disease?

Kawasaki disease, also called Kawasaki syndrome and mucocutaneous lymph node syndrome, is an early childhood illness that causes inflammation in the medium-sized arteries in the body. Because it can affect the coronary arteries, it can potentially lead to coronary artery aneurysms and sudden death.

The acronym "FEBRILE" is useful for remembering the signs and symptoms of Kawasaki disease:

• Fever
• Enanthem (mucous membrane rash and lip cracking)
• Bulbar conjunctivitis (eye redness)
• Rash -- often begins in the genital area but can also occur on the chest, back, abdomen, arms, and legs
• Internal organ involvement (not part of the criteria)
• Lymphadenopathy -- swollen glands in the neck
• Extremity changes -- red, swollen skin on the palms of the hands and soles of the feet. After a few days, skin peels on the fingertips and toes.

Other symptoms and signs of Kawasaki disease include

• cracked, red lips; and a
• red, swollen tongue.

The cause of Kawasaki disease is unknown. Medical researchers suspect there may be an infectious cause such as a virus, however, they have not identified a specific infectious agent.

Other possible causes for Kawasaki disease include

• autoimmune reactions,
• systemic inflammation secondary to an infection such as a virus, and a
• genetic predisposition.

Kawasaki disease has two forms: complete and incomplete.

The criteria for diagnosis of complete Kawasaki disease includes:

• Fever of at least 5 days along with 4 or 5 of the principal clinical features.

The principal clinical features include the following:

• Changes in extremities
• Tiny red bumps caused by sun sensitivity (polymorphous rash)
• Changes in the tissues of the mouth and throat
• Painless eye redness that is non-oozing, limbic sparing (the sclera around the iris stays white), and affects both eyes
• Acute one-sided, non-itching enlarged lymph nodes in the neck (lymph node diameter greater than 1.5 cm)

The criteria for diagnosis of incomplete Kawasaki disease includes:

• Fever of at least 5 days or longer along with 2 or 3 of the principal clinical features
• Laboratory findings suggestive of the disease or heart abnormalities detected on echocardiogram
  • Laboratory findings include the following:
    • Elevated erythrocyte sedimentation rate (ESR)
    • Elevated C-reactive protein (CRP)
    • Hypoalbuminemia
    • Low iron (anemia)
    • Elevated alanine aminotransferase (ALT)
    • Elevated platelet levels (thrombocytosis)
    • Elevated white blood cell counts (leukocytosis)
    • Elevated white blood cells in the urine (pyuria)

The main goal of treatment for Kawasaki disease is to prevent coronary artery aneurysms and other cardiac complications.

The main treatments for Kawasaki disease include

• intravenous immunoglobulin (IVIG) and
• aspirin.

About 10%-15% of patients will fail initial treatment with IVIG. In those patients, treatment may include the following:

• A second dose of IVIG
• Methylprednisolone
• A longer tapering course of prednisolone or prednisone plus IVIG
• Infliximab (Remicade)

In extreme treatment-resistant cases, the American Heart Association recommends

• cyclosporine and other cytotoxic agents,
• immunomodulatory monoclonal antibody therapy, and
• plasma exchange.

Other medications that may be used include the following:

• Statins
• Pentoxifylline
• Abciximab
• Corticosteroids, though research on their effectiveness for Kawasaki disease is mixed

Because Kawasaki disease can affect the coronary arteries, it can potentially lead to coronary artery aneurysms in about 25% of cases. Coronary artery aneurysms can lead to sudden death.

Other cardiovascular complications include the following:

• Heart failure or heart dysfunction (not likely to occur once the fever goes away)
• Heart attack
• Inflammation of the heart muscle (myocarditis)
• Inflammation of heart valves (typically the mitral valve)
• Inflammation of the sac that surrounds the heart (pericarditis)
• Systemic arterial aneurysms
• Rupture of coronary artery aneurysms with hemopericardium

If a patient does not develop a coronary artery aneurysm, they will recover fully. The mortality from Kawasaki disease is less than 0.5%, with the highest risk in the first year after disease onset. Acute heart attack due to giant aneurysms is typically the cause of death.

If a patient develops a coronary artery aneurysm, the severity of aneurysm will affect the prognosis. More than half of all aneurysms resolve within 2 years, however, blood flow in the blood vessels may remain abnormal even after healing, and patients may have an increased risk of premature coronary artery disease.