Kawasaki Disease

Key Points
Condition resulting in the inflammation of small and medium blood vessels in the body
Exact cause is unknown, but it is thought to be the result of a reaction to a common infectious bacteria or other organism
Primarily affects the heart, with other sites being affected less frequently
Cutaneous symptoms consist of an itchy rash of variable form which appears on the arms, legs, groin and trunk often with swelling of the extremities. Red eyes and a red “strawberry” tongue are sometimes seen along with cracked fissured lips

Kawasaki disease is classified as an acute febrile disease in which the small and medium blood vessels of the body become inflamed, especially around the heart. Initial cutaneous symptoms consist of an itchy rash of variable form which appears on the arms, legs, groin and trunk. The condition typically progresses through four stages.

In the acute stage, appearance of the body rash is accompanied by sudden fever which does not respond to treatment, red eyes, redness and spotting on the tongue, swelling in the extremities, enlarged glands, and heart complications such as myocarditis and pericarditis. This stage typically lasts from 1-11 days. The subacute stage, which can last up to 10 days, sees the resolution of fever, rash and gland enlargement. Red eyes, irritability and poor appetite will persist, and may be accompanied by thrombocytosis (which may lead to clot formation), joint and muscle pain. Further heart conditions including aneurysms may develop during the subacute stage. The convalescent stage, which may last over a month, sees the resolution of most clinical symptoms, though heart problems may continue. The last stage of the condition is the late-stage or chronic stage. Within 2 years of the initial resolution of the condition, some heart issues, including aneurysms, may improve. Any heart conditions which result from Kawasaki disease may persist over the lifetime of the affected person.

The exact cause of Kawasaki disease is unknown, though it is thought that it may be the result of a reaction to a common infectious bacteria or other organism. It may also be due to genetic factors and/or immune system abnormalities. It is far more frequent among those persons of Japanese descent than others, and a family history of the condition increases risk of its development.

Differential Diagnosis (Other conditions with similar appearance)
Infantile Polyarteritis nodosa
Staphylococcus Aureus Infection
Juvenile Rheumatoid arthritis
Streptococcal Infection, Group A
Leptospirosis
Toxic shock syndrome
Measles
Toxicity, Mercury
Rheumatic Fever
Rheumatic Heart Disease
Rocky Mountain spotted fever

Diagnosis
Key Points
Diagnosis based on specific clinical criteria
Heart tests may be performed to confirm the diagnosis or determine the extent of the condition

No specific tests exist to diagnose Kawasaki disease. Diagnosis is based on a combination of specific clinical criteria. In addition to a prolonged high fever which does not respond to Antibiotics, affected persons must show 4 of the 5 five following symptoms: changes in the extremities (swelling, redness, followed by peeling), rash, red eyes, changes to the mouth, tongue and lips, and gland enlargement in the neck. In atypical cases (those who do not meet clinical criteria), heart tests may be performed to confirm the diagnosis. These tests can also assist in determining the extent of the condition and its effect on the heart.

Treatment
Treatment initially consists of prescription antibiotics until other conditions are excluded.
Main goal of initial treatment is management of fever and inflammation
*Primary treatment during initial stages consist of Immunoglobulin Injections and aspirin to reduce fever

Treatment of Kawasaki disease initially consists of prescription antibiotics, until such time as other conditions are excluded. Once diagnosis is confirmed, the main goal of treatment is to manage the high fever of the acute stage and to alleviate inflammation to prevent further damage to the heart. This is accomplished through a high does aspirin regimen (to reduce fever) and Immunoglobulin Injections (lowers risk of heart complications). Aspirin regimens should be maintained until the fever is gone and for a short time afterward, and may be continued indefinitely depending on the severity of any heart abnormalities.