A 52-year-old woman presents with xanthomas on her eyelids and Achilles tendons, along with premature coronary artery disease. Laboratory studies show LDL cholesterol of 420 mg/dL despite atorvastatin 80 mg daily, HDL of 35 mg/dL, and normal triglycerides. Her father and paternal grandfather both had myocardial infarctions in their 40s. Which of the following is the most likely genetic defect?
- A)Loss-of-function mutation in apolipoprotein B-100
- B)Gain-of-function mutation in PCSK9
- C)Loss-of-function mutation in the LDL receptor geneGABARITO
- D)Loss-of-function mutation in lipoprotein lipase
- E)Gain-of-function mutation in HMG-CoA reductase
Explicação
Familial hypercholesterolemia due to LDL receptor deficiency causes severe LDL elevation (often >300 mg/dL), tendon xanthomas, and premature CAD. Heterozygous mutations affect ~1 in 500 people; homozygous mutations cause even more severe disease. Statins have ... Ver explicação completa e trilha adaptativa →