BACKGROUND Delineation of lipid values in children after Kawasaki syndrome is important because of the predilection of this disease for the coronary arteries. METHODS AND RESULTS We measured plasma concentrations of total cholesterol, high density lipoprotein (HDL) cholesterol, and triglycerides using enzymatic methods in 105 patients with a history of Kawasaki syndrome. Measurements were obtained during six time periods: 10 days or less, 11-31 days, 1-3 months, 3-12 months, 1-3 years, and more than 3 years. Total cholesterol was depressed in the first interval (122.0 +/- 19.8 mg/dl, mean +/- SD), but the mean values were normal in all periods after clinical recovery (overall mean, 149.0 +/- 24.0 mg/dl). High density lipoprotein cholesterol was also depressed in the first interval (15.2 +/- 9.9 mg/dl); although high density lipoprotein cholesterol increased significantly with duration since disease onset (p less than 0.001), it remained significantly lower than expected (p less than 0.001), even in the latest interval (47.2 +/- 10.9 mg/dl). Nonfasting triglyceride levels were high (162.5 +/- 63.4 mg/dl) in the first interval and then diminished steadily with time, but this relation did not achieve statistical significance. We compared adjusted lipid levels (z scores) of 46 Kawasaki patients after clinical recovery with those of their parents; patients had similar total cholesterol levels but significantly lower high density lipoprotein cholesterol levels (p = 0.021 for mothers, p = 0.001 for fathers). Mean high density lipoprotein cholesterol after clinical recovery tended to be lower in patients with persistent coronary abnormalities than in those without such lesions (p = 0.085). CONCLUSIONS Kawasaki syndrome is associated with important abnormalities in lipid metabolism. Continued long-term surveillance of this population is necessary to monitor lipid levels and their relation to future development of coronary atherosclerosis.