Remarkably increased cholesteryl ester-dominant apoE-rich HDL with alpha 2-mobility, similar to the apoE-rich HDL observed in primary biliary cirrhosis, was found in a patient with acute bile duct obstruction due to common bile duct carcinoma. Bile drainage rapidly lowered her serum apoE-rich HDL from 34.1 to 6.1 mg/dl and from 96 to 10 mg/dl in terms of apoE (control; 2.6 +/- 1.5 mg/dl, n = 38) and of cholesterol (control; 6.7 +/- 2.3 mg/dl, n = 38), respectively. Disturbance in hepatic lipoprotein clearance due to the presence of cholestasis without severe liver damage is a possible cause of accumulation of cholesteryl ester-dominant apoE-rich HDL. Hence, plasma cholesteryl ester-dominant apoE-rich HDL level is supposed to be a good indicator of hepatic lipoprotein clearance. The measurement of this lipoprotein and the analysis of its lipid composition, by our convenient method, would be useful for the diagnosis of cholestasis and for the evaluation of hepatic function in cholestatic patients.