Diagnosis of Coronary Artery Abnormalities in Kawasaki Disease: Recent Guidelines and Z Score Systems

Kawasaki disease is an acute systemic vasculitis affecting children and the leading cause of acquired heart disease in developed countries. This vasculitis has a predilection for the coronary arteries, and coronary artery abnormalities are the main criteria for diagnosis. The diagnosis of coronary abnormalities has been based on dichotomous criteria for a long time, but recent guidelines have accepted the body surface area adjusted z score system to define coronary abnormalities and classify coronary artery aneurysms. Z score systems have improved risk classifications of coronary aneurysms and showed better correlation with clinical prognosis. However, the discrepancy of calculated z scores according to the formula has been noticed in the application of the z score system, which possibly affects the diagnosis of coronary artery abnormalities. This variability was greater in larger coronary aneurysm dimensions. A careful choice of the z-score formula and its consistent use is needed in clinical applications.