Kawasaki disease is an autoimmune condition causing inflammation of arterial vessels in children, usually before the age of five. Disease prognosis varies from patient to patient whether they are treated or not but the general outline for prognosis is:

• Early detection and treatment of Kawasaki disease usually results in complete recovery within six to eight weeks of symptom onset. The risk of complications such as coronary artery disease and coronary artery aneurysms is also markedly reduced.
• In children who have not been treated, Kawasaki disease may be self limiting and resolve independently of treatment. However, there remains a risk of complications, particularly involvement of the coronary arteries.
• All children who have had Kawasaki disease need to have a cardiac echocardiogram or ultra sonography of the heart every few weeks and then every one or two years, to check for coronary artery inflammation or vasculitis. Vasculitis may lead to the formation of balloon-like swellings in the coronary arteries called aneurysms that are at risk of rupturing. Around 5% of all children are likely to develop coronary artery vasculitis as a long term complication of Kawasaki disease.
• Another outcome is a relapse of the condition after initial treatment with intravenous immunoglobulins. In this case, the child needs to be re-admitted to hospital and treatment started afresh. The antibodies administered may also lead to severe allergic reactions. Children who have received this treatment must not be vaccinated against measles for 12 months or against chicken pox for at least five months afterwards.