Decreased serum cholesteryl-ester transfer activity in a patient with familial hyperalphalipoproteinemia

Lipoprotein patterns and cholesteryl-ester transfer activity (CETA) were examined in a patient with familial hyperalphalipoproteinemia (FHALP). The proband was a 41-year-old Japanese male. He was found to have hypercholesterolemia, with a serum total cholesterol level of 382 mg/dl and a HDL-cholesterol level of 177 mg/dl. HDL showed a high cholesterol/Apo AI ratio. His father, all of his siblings and one of his children showed high HDL-cholesterol levels (91, 100, 70, 108, 75 and 98 mg/dl, respectively). These data suggest that all members of his family were heterozygotes. He had neither cutaneous or tendinous xanthomas nor any clinical signs of atherosclerosis. The proband appears to have only one-tenth of the normal level of CETA. However, the level of lipid-transfer protein I (LTP-I) activity was near normal. Thus, this patient is most likely to have an exaggerated level of LTP-I inhibitor(s). Effects of probucol on serum lipoprotein and apolipoprotein levels were studied in our patient. Treatment with 250 mg of probucol twice daily reduced total serum cholesterol, low density lipoprotein (LDL) and HDL-cholesterol levels by 33.32 and 33%, respectively. Apo AI, B and E levels decreased by 22, 16 and 35% respectively. HDL-cholesterol/Apo AI ratio decreased from 0.9 to 0.76. CETA showed no significant changes. However, cholesterol ester mass transfer increased from 10.8 to 14.9% after treatment with probucol. These results suggest that probucol appears to be a useful drug for FHALP.