A Case of Symptomatic Hypobetalipoproteinemia with Unusual Distribution of Apolipoprotein E.

A case of symptomatic hypobetalipoproteinemia (hypo-beta LP) with unusual distribution of apolipoprotein E (apo E) in a 68-year-old male patient with chronic heart failure and liver cirrhosis associated with low triiodothyronine (T3) syndrome is reported. There was nothing in the family history to suggest familial hypo-beta LP. In this case, levels of apo B and low-density lipoprotein were very low, and the fraction of beta lipoprotein on polyacrylamide-gel disc electrophoresis (PAGE) was only 7%. However, the triglyceride level was normal due to the presence of chylomicron, in spite of hypocholesterolemia and hypophospholipidemia. The mid-band lipoprotein on PAGE showed that Lp (a) lipoprotein concentration was normal (18.3 mg/dl). The activities of lecithin cholesterol acyltransferase, hepatic triglyceride lipase and lipoprotein lipase (LPL) were low. The concentrations of apo C-II, apo C-III and apo E were low, while those of apo A-I and apo A-II were normal. The author recently reported that the apo C of high-density lipoprotein (HDL-apo C) was detected in alpha lipoprotein, but that HDL-apo E was detected in the near alpha 2-globulin region behind alpha lipoprotein on agarose-gel immunofixation electrophoresis. The author therefore named it alpha 2-apo E, and later found that the fraction percentage of alpha 2-apo E depends on lipolysis and is inversely correlated to the concentration of apo B.(ABSTRACT TRUNCATED AT 250 WORDS)