Abstract
Type III hyperlipoproteinemia (HLP) is a disorder characterized by abnormal accumulation of intermediate density lipoprotein (IDL, remnant) and premature atherosclerosis. Only a few cases of type III HLP secondary to diabetes mellitus without ketoacidosis have been reported in Japan.
A 68-year-old male diabetic patient with type III HLP, femoral arterial occlusion and myocardial infarction is described in this paper. He was admitted to our hospital due to of intermittent claudication. He had suffered from myocardial infarction 8 years previously, and was then readmitted to our clinic several times complaining of dyspnea.
The patient had received acetohexamide (500 mg/day) until 6 months prior to admission, and was thereafter treated with insulin.
The plasma cholesterol and triglyceride levels on admission were 303 and 393 mg/dl, respectively. Agarose gel electrophoresis revealed broad beta bands. The values for the cholesterol in VLDL (d<1.006 g/ml), VLDL-cholesterol to VLDL triglyceride ratio, and VLDL-cholesterol to total triglyceride ratio were 113 mg/dl, 0.43, and 0.302, respectively, and were compatible with the laboratory diagnostic criteria of type 1ff HLP. The electrophoretic pattern changed from type III to type II b after treatment by diet and insulin. Both the postheparin lipoprotein lipase and hepatic lipase activities were normal.
Three phenotypes, ApoE-N, ApoE-ND, and ApoE-D (E-III deficiency pattern), were differentiated on the basis of the ApoE- II /ApoE-III ratios by isoelectric focusing of ApoVLDL. The ratio was 0.74 in the present case, which was compatible with ApoE-ND.Such an ApoE composition may contribute to the development of type III HLP secondary to diabetes mellitus. It is concluded that such abnormal lipoprotein metabolism may play an important role in the development of severe atherosclerotic vascular disease in diabetes mellitus.
