Medicine & USMLE

Familial Hypertriglyceridemia

  1. Chylomicron Metabolism
  2. VLDL Metabolism
  3. HDL Metabolism
  4. Abetalipoproteinemia
  5. Familial Hyperchylomicronemia
  6. Familial Hypercholesterolemia
  7. Familial Dysbetalipoproteinemia
  8. Familial Hypertriglyceridemia


Familial hypertriglyceridemia, also known as type IV hyperlipoproteinemia, is an autosomal dominant disorder that is defined by an isolated elevation of VLDL. This may have a number of possible causes, such as a heterozygous LPL-inactivating mutation, a hepatic overproduction of VLDL, or a decrease in VLDL clearance. Since VLDL carries triglycerides, hypertriglyceridemia is therefore a hallmark of the disease. High triglyceride levels are also a common cause of pancreatitis, which therefore may also be seen. Finally, the disease is often accompanied by insulin resistance.

Key Points

  • Familial Hypertriglyceridemia
    • Also known as type IV hyperlipoproteinemia
    • Genetics
      • Autosomal dominant
        • This disease is fairly common
    • Pathophysiology
      • Possible causes:
        • Heterozygote for LPL-inactivating mutation
        • Hepatic overproduction of VLDL
        • Decreased removal of VLDL
    • Clinical Features
      • Elevated VLDL elevated triglycerides
        • This is the definition of familial hypertriglyceridemia
        • Compare / contrast with familial hyperchylomicronemia, which is also characterized by elevated VLDL / triglycerides
      • Pancreatitis
        • Caused by increased triglycerides
      • Often accompanied by insulin resistance
        • You may get premature atherosclerosis because of this, but you shouldn’t think of this familial hypertriglyceridemia as one of the CVD hyperlipoproteinemias. Those are hyperlipoproteinemias types II and III.
      • No CVD / premature atherosclerosis
      • Turbid serum
        • Contrast against familial hyperchylomicronemia, in which the serum has a creamy layer
        • I like to think of familial hypertriglyceridemia as a less severe form of familial hyperchylomicronemia