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Pathophys and Cause ⬇

Cause:Genetic, autosomal dominant

Pathophys:Decreased LDL receptors cause increased LDL and sometimes VLDL (Nejm 1986;314:879); or, more rarely due to mutations in apolipoprotein B gene, which impairs receptor binding (Nejm 1998;338:1577). Apolipoproteins of LDL and HDL correlate better with familial risk than the cholesterol levels in each component (Nejm 1990;322:1494; 1986;315:721). Uremia and -blockers decrease HDL

Epidemiology ⬆ ⬇

Common, 1/200 prevalence

Signs and Symptoms ⬆ ⬇

Si:Arcus senilis, tendinous xanthomata (80% over age 20 yr have them), tuberous xanthomata in homozygotes, xanthelasmas (only 50% in a general population are associated with type II disease, ie, 50% specif)

Course ⬆ ⬇

Malignant; MIs in pts age 30-40 yr, even in teens in homozygotes

Complications ⬆ ⬇

Increased ASHD with MIs

r/o secondary causes of hypercholesterolemia (Hypercholesterolemia)

Lab and Xray ⬆ ⬇

Lab: Chem:Cholesterol very high, with high LDL; triglycerides normal in IIa, slightly elevated in IIb; supranate and infranate clear in both, PHLA normal in both.

Treatment ⬆

Rx:

Standard rx of hypercholesterolemia (Hypercholesterolemia), statins + resins more effective than either alone; probably safe and helpful in children by age 10 yr (Jama 2004;292:331, 377)

Liver transplant in severe familial (Ann IM 1988;108:204)