Kawasaki disease

Lymphatic system	Kawasaki’s disease, peeling of the fingertips	Kawasaki’s disease - edema of the hand

Alternative names

Mucocutaneous lymph node syndrome; Mucocutaneous lymph node disease; Infantile polyarteritis

Definition

A non-specific disease, with no apparent infectious agent, that affects the mucus membranes, lymph nodes, lining of the blood vessels, and the heart.

Causes and risks

The cause of Kawasaki disease has not been determined. The incidence is high in Japan where the disease was first described and is recognized now more frequently in the United States. Other risk factors than age are unknown. Kawasaki disease is predominatly a disease of young children, with 80% of patients younger than 5 years of age.

Kawasaki disease is a poorly understood illness. It appears in many respects to be an immune vasculitis (an autoimmune disorder). It is precipitated by unknown outside factors. The disorder affects the mucus membranes, lymph nodes, lining of the blood vessels and the heart. The cardiac involvement and complications are, by far, the most important aspect of the disease. Kawasaki disease can cause vasculitis (inflammation of blood vessels) in the coronary arteries and subsequent coronary artery aneurysms. These aneurysms can lead to myocardial infarction (heart attack) even in young children (rarely). About 20 - 40% of children with Kawasaki disease will have evidence of vasculitis with cardiac involvement.

Kawasaki disease often begins with a high and persistent fever that is not very responsive to normal doses of acetaminophen or ibuprofen. The fever may persist steadily for up to two weeks. The children develop red eyes, red mucous membranes in the mouth, red cracked (fissured) lips, a "strawberry tongue", and swollen lymph nodes. Skin rashes may occur early in the disease and peeling of the skin in the groin (genital area), hands, and feet (especially around the nails and on the palms and soles) may occur.

The changes in the coronary arteries can only be demonstrated by testing. Echocardiography (non-invasive) or angiography, a study in which dye is injected into the blood stream and the heart and its coronary arteries viewed or X-ray may be used.

Prevention

There are no known measures that will prevent this disorder.

Symptoms

• fever that is high grade (greater than 102 degrees Fahrenheit and often 104 degrees) and remaining elevated more than three days. A persistant fever lasting at least five days is considered a hallmark sign
• fever that is relatively unresponsive to antipyretics (fever-reducing medications) or ibuprofen
• extremely bloodshot or red eyes (conjunctivitis without pus or drainage)
• bright red lips (chapped appearing, may crack)
• red mucous membranes in the mouth
• strawberry tongue, white coating on the tongue and prominent red bumps (papillae) on the back of the tongue
• the palms of the hands and the soles of the feet are red
• the hands and feet may be swollen
• the palms and soles may peel (desquamate) later in the illness; peeling may begin around the nails
• rashes similar to erythema multiforme
  • rash, NOT blister-like, on the trunk (may occur)
• swollen lymph nodes (lymphadenopathy), particularly in the neck area. Frequently only one lymph node is swollen (usually in the neck region)
• joint pain (arthralgia) and swelling, frequently symmetrical

Signs and tests

A physical examination will demonstrate many of the symptoms listed above. Procedures such as ECG and echocardiography may reveal signs of myocarditis, pericarditis, arthritis, aseptic meningitis, and (or) coronary vasculitis.

Tests include:

• CBC
• ESR
• electrocardiogram
• echocardiogram
• chest X-ray
• urinalysis
  • may show pus in the urine (pyuria)
  • may show protein in the urine (proteinuria)

Treatment

Children with Kawasaki disease are hospitalized and care is normally shared between pediatric cardiology and infectious disease specialists (although no infectious agent has been demonstrated). It is imperative that treatment 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. Marked improvement is usually noted within 24 hours of treatment with IV gamma globulin.

Salicylate therapy, particularly aspirin remains an important part of the treatment but salicylates alone are not as effective as IV gamma globulin.

Prognosis

With early recognition and treatment, full recovery can be expected. However, 2% die from complications of coronary vasculitis. Patients who had Kawasaki disease should have an echocardiogram every 1-2 years to screen for progression of cardiac involvement.