Fredrickson&;s type II hyperlipoproteinemia is due to excess amounts of
## **Core Concept**
Fredrickson's classification is a system used to categorize hyperlipoproteinemias based on the types of lipoproteins elevated in the blood. Type II hyperlipoproteinemia is characterized by elevated levels of low-density lipoproteins (LDL), which are rich in cholesterol.
## **Why the Correct Answer is Right**
The correct answer, **B. LDL (Low-Density Lipoproteins)**, is right because Type II hyperlipoproteinemia, also known as familial hypercholesterolemia, is primarily due to an excess of LDL cholesterol in the blood. This condition results from defects in the LDL receptor gene, leading to decreased clearance of LDL from the plasma. LDL is often referred to as "bad cholesterol" because high levels can lead to plaque buildup in arteries and result in cardiovascular disease.
## **Why Each Wrong Option is Incorrect**
- **Option A:** VLDL (Very Low-Density Lipoproteins) is incorrect because, although VLDL is also a lipoprotein that carries endogenous triglycerides, Type II hyperlipoproteinemia is specifically associated with elevated LDL levels, not VLDL.
- **Option C:** Chylomicrons are incorrect because they are primarily involved in transporting dietary triglycerides from the intestines to other parts of the body and are not directly associated with Type II hyperlipoproteinemia.
- **Option D:** HDL (High-Density Lipoproteins) is incorrect because HDL, or "good cholesterol," is involved in removing excess cholesterol from cells and transporting it to the liver for excretion. Type II hyperlipoproteinemia is not characterized by an excess of HDL.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that patients with Type II hyperlipoproteinemia are at a high risk of premature atherosclerotic cardiovascular disease. Early diagnosis and treatment, often involving statins and lifestyle modifications, are crucial to prevent or delay the onset of cardiovascular events.
## **Correct Answer:** B. LDL (Low-Density Lipoproteins)