Type III hyperlipoproteinemia exaggerated by Sheehan's syndrome with advanced systemic atherosclerosis - A 28-year clinical course

A 38-year-old Japanese woman was admitted to hospital for further examination of systemic xanthomas. She had a past history of genital bleeding during her third delivery at the age of 21 years. She was diagnosed with Sheehan's syndrome. Her serum total cholesterol and triglyceride concentrations were 500 and 898 mg/dl, respectively. She was also diagnosed as having type III hyperlipoproteinemia on the basis of the presence of a broad-beta-band on agarose gel electrophoresis and extremely high concentrations of very-low-density lipoprotein cholesterol (310 mg/dl). The diagnosis was. later confirmed by her apolipoprotein E isoforms (E2/E2) and genotypes (epsilon2/epsilon2). Thyroid and corticosteroid hormone replacement therapy cured the xanthomas, but also elevated her blood pressure. The serum concentration of intermediate-density lipoprotein cholesterol was consistently high, whereas that of low-density lipoprotein cholesterol was relatively low during the follow-up. Coronary atherosclerosis had already developed by the age of 38 years, and progressed significantly over the following 28 years. Severe stenotic lesions were observed in the bilateral renal arteries and carotid arteries, and in the abdominal aorta when she was 66 years old. These findings suggest that the continuous elevation of intermediate-density lipoprotein cholesterol for a long period contributed to the development of the atherosclerotic lesions.