Kawasaki disease (KD), most popular acquired heart disease in childhood, is characterized by diffuse vasculitis, especially on the middle-sized muscular arteries. IVIG and aspirin are currently standard treatment. However, 10-15% of KD patients have poor response to such treatment and suffer from higher risk of coronary involvement. Recently, combination of prednisolone and IVIG has been shown effective to lower the chance of refractory to IVIG treatment and subsequent coronary lesions. However, no randomized trial on the steroid efficacy was ever conducted in Taiwan.