A 42-year-old man comes to the physician for an examination prior to beginning an exercise program at a local health club. He has smoked 1 pack of cigarettes daily for 20 years. He is 183 cm (6 ft) tall and weighs 70 kg (155 lb); BMI is 21 kg/m2. His blood pressure is 130/80 mm Hg. Physical examination shows no other abnormalities. Serum studies show: Cholesterol, total: 350 HDL-cholesterol: 40 LDL-cholesterol: 280 Triglycerides: 150 Which of the following defects is the most likely cause of this patient's increased serum LDL-cholesterol concentration? A) Decreased ability to convert cholesterol to bile acids B) Decreased clearance of cholesterol by the liver C) Increased absorption of cholesterol in the gut D) Increased production of cholesterol by adipose tissue E) Increased production of cholesterol by the liver
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The most common of these is familial hypercholesterolemia (FH), an autosomal dominant disorder characterized by elevated LDL-cholesterol levels due to defective or absent LDL receptors. LDL receptors on hepatocytes bind LDL in the circulation and internalize it, Show more…
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