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Definition of Familial hypercholesterolemia

< b>Familial hypercholesterolemia: The most common inherited type of hyperlipidemia (high lipid levels in blood). One in every 500 children is born with familial hypercholesterolemia. The condition predisposes to premature arteriosclerosis including coronary artery disease with heart attacks at an unusually young age.

Persons with familial hypercholesterolemia can reduce their risk by adhering to a very low cholesterol diet under a doctor's supervision, and may also need to take medications such as the statins that reduce their cholesterol level.

Children with hypercholesterolemia can be detected because they usually have an LDL cholesterol that is elevated over 190. Children and other relatives at risk for familial hypercholesterolemia should be screened for the condition and treated if they have it. Statin therapy produces significant regression of atherosclerosis in children and adults with familial hypercholesterolemia. Children on statin therapy reportedly have had no adverse effects on growth, sexual maturation, hormone levels, the liver, or muscle.

Familial hypercholesterolemia is usually due to a genetic defect in the receptor for LDL (low density lipoprotein). The most common autosomal dominant form of hypercholesterolemia is caused by mutation in the LDL receptor gene (LDLR) on chromosome 19 in band 19p13.2. There are a number of other less frequent forms of this disorder. They include type B hypercholesterolemia which is caused by ligand-defective apolipoprotein B-100 (APOB); and autosomal dominant hypercholesterolemia 3 (HCHOLA3) which is caused by mutation in the PCSK9 gene.