PURPOSE: The value of serum lipid in children after recovery of Kawasaki disease may be important because of the predilection of this disease for the coronary artery. METHODS: We measured serum high density lipoprotein (HDL)-cholesterol, total cholesterol, triglycerides in 22 patients (mean age 38months, range 6 to 93 months) with Kawasaki disease during 10 days or less after onset and 2 months later after recovery. RESULTS: The level of serum HDL-cholesterol was depressed in the acute stage compaired with the level after recovery (33.6+/-15.2mg/dl vs. 54.8+/-8.3mg/dl, mean+/-S.D., p<0.05). Total cholesterol, triglycerides were normal during the acute stage (125.3+/-46.1mg/dl, 142.1+/-32.2mg/dl, respectively) and after recovery (147.4+/-35.5mg/dl, 130.6+/-74.9mg/dl, respectively). Echocardiography confirmed coronary aneurysm in 7 patients (31.8%) and otherwise, normal coronary figures (n=15). In the patients with coronary aneurysm, the level of serum total cholesterol, HDL-cholesterol were 134.0+/-34.1mg/dl, 34.5+/-14.9mg/dl, respectively and in the patients without coronary aneurysm 147.7+/-36.7mg/dl, 29.5+/-12.8mg/dl, respectively. They showed no significant differences between two groups (p=0.5, p=0.43, respectively). CONCLUSIONS: Significantly reduced HDL-cholesterol level, which is considered a risk factor for coronary atherosclerosis, is transient finding in the acute stage of Kawasaki disease and not associated with the incidence of coronary aneurysm. Further basic research is needed to elucidate the pathophysiology by which this abnormality is produced.