Study Reference
Important inherited hyperlipoproteinemias
Familial chylomicronemia syndrome (type I)
Protein defect: Lipoprotein lipase, ApoC-2
Elevated lipoproteins: Chylomicrons
Major manifestations: Acute pancreatitis, Lipemia retinalis, Eruptive xanthomas
Familial hypercholesterolemia (type II A)
Protein defect: LDL receptor, ApoB-100
Elevated lipoproteins: LDL
Major manifestations: Premature atherosclerosis, Tendon xanthomas, Xanthelasmas
Familial dysbetalipoproteinemia (type III)
Protein defect: ApoE
Elevated lipoproteins: Chylomicron & VLDL remnants
Major manifestations: Premature atherosclerosis, Tuboeruptive & palmar xanthomas
Familial hypertriglyceridemia (type IV)
Protein defect: Polygenic
Elevated lipoproteins: VLDL
Major manifestations: Associated with coronary disease, pancreatitis & diabetes
Study Mnemonics & Tips
- Type 1 (1 is "C"): Chylomicrons, ApoC-II, and "Creamy" blood (lipemia retinalis). Note that there is no increased risk for atherosclerosis here, only pancreatitis.
- Type 2 (2 is "B"): Bad cholesterol (LDL) and ApoB-100. Think of "Tendon" xanthomas (Achilles).
- Type 3 (3 is "E"): ApoE is the defect. Remnants are not cleared. Look for the "Palmar" xanthoma (the number 3 looks like the curves of a palm).
- Type 4 (4 is "V"): VLDL is high. This is the most common and is often seen with Metabolic Syndrome/Diabetes.