Primary amenorrhoea and xanthomatosis

Our patient had primary amenorrhoea, skeletal, and sexual immaturity, caused by hypothalamic-pituitary dysfunction due to primary hypothyroidism.1,2 Juvenile hypothyroidism may cause isosexual pseudoprecocity, galactorrhoea, menorrhagia, short stature, poor scholastic performance, macroorchidism, and hypertrophic myopathy. Type III hyperlipoproteinaemia has a prevalence of 0.01-0.4%. Although 1% of the population is homozygous for ApoE2, most homozygous individuals have normal lipid profiles, until compensatory mechanisms are compromised by a second defect in lipid metabolism caused by conditions such as hypothyroidism, obesity, diabetes, or alcoholism.1 Inheritance is autosomal recessive, and peripheral vascular disease is a common feature. Pathognomonic xanthoma planum occurs in 50% of patients,3 while xanthoma tuberosum is non-specific. The increased concentrations of lipoproteins are mostly due to remnants such as [beta]-VLDL. Increased triglycerides and cholesterol contribute to the lipid fraction. Low oestrogen concentrations slow clearance of lipoprotein remnants. Virtually all women with type III hyperlipoproteinaemia are post-menopausal, and the lipid profile returns to normal with therapeutic oestrogen.3,5 Hypothyroidism also impairs clearance of lipoprotein remnants and modulates the phenotype of type III hyperlipoproteinaemia, which responds to L-thyroxine.1,4 LDL cholesterol increases in clinical and subclinical hypothyroidism and causes hypercholesterolaemia. Hypertriglyceridaemia occurs if obesity co-exists.