The highest rate of progression to stenosis occurs among those who develop large aneurysms. The worst prognosis occurs in children with giant aneurysms. This severe outcome may require further treatment such as percutaneous transluminal angioplasty, coronary artery stenting, bypass grafting, and even cardiac transplantation.A relapse of symptoms may occur soon after initial treatment with IVIG. This usually requires rehospitalization and retreatment. Treatment with IVIG can cause allergic and nonallergic acute reactions, aseptic meningitis, fluid overload, and rarely, other serious reactions. Overall, life-threatening complications resulting from therapy for Kawasaki disease are exceedingly rare, especially compared with the risk of nontreatment. Evidence indicates Kawasaki disease produces altered lipid metabolism that persists beyond the clinical resolution of the disease.Rarely, recurrence can occur in Kawasaki disease with or without treatment. Epidemiology
Kawasaki disease affects boys more than girls, with people of Asian ethnicity, particularly Japanese people. The higher incidence in Asian populations is thought to be linked to genetic susceptibility. Incidence rates vary between countries. Currently, Kawasaki disease is the most commonly diagnosed pediatric vasculitis in the world. By far, the highest incidence of Kawasaki disease occurs in Japan, with the most recent study placing the attack rate at 218.6 per 100,000 children less than five years of age (about one in 450 children). At this present attack rate, more than one in 150 children in Japan will develop Kawasaki disease during their lifetimes.However, its incidence in the United States is increasing. Kawasaki disease is predominantly a disease of young children, with 80% of patients younger than five years of age.
Kawasaki disease is a syndrome of unknown cause that results in a fever and mainly affects children under 5 years of age. It is a form of vasculitis, where blood vessels become inflamed throughout the body. The fever typically lasts for more than five days and is not affected by usual medications. Other common symptoms include large lymph nodes in the neck, a rash in the genital area, lips, palms, or soles of the feet, and red eyes. Within three weeks of the onset, the skin from the hands and feet may peel, after which recovery typically occurs. In some children, coronary artery aneurysms form in the heart.While the specific cause is unknown, it is thought to result from an excessive immune system response to an infection in children who are genetically predisposed. It does not spread between people. Diagnosis is usually based on a persons signs and symptoms. Other tests such as an ultrasound of the heart and blood tests may support the diagnosis. Diagnosis must take into account many other conditions that may present similar features, including scarlet fever and juvenile rheumatoid arthritis. An emerging Kawasaki-like disease temporally associated with COVID-19 appears to be a distinct syndrome.Typically, initial treatment of Kawasaki disease consists of high doses of aspirin and immunoglobulin. Usually, with treatment, fever resolves within 24 hours and full recovery occurs. If the coronary arteries are involved, ongoing treatment or surgery may occasionally be required. Without treatment, coronary artery aneurysms occur in up to 25% and about 1% die.