A 45-year-old man with premature coronary artery disease (diagnosed at age 42) presents with yellow nodules on his elbows and Achilles tendons, plus corneal arcus. Vital signs: BP 148/92 mmHg, HR 88/min, RR 14/min, temp 37°C. Laboratory studies reveal LDL cholesterol 520 mg/dL, triglycerides 95 mg/dL (normal), and HDL cholesterol 38 mg/dL. Coronary angiography confirms significant stenosis. Which genetic defect best explains his phenotype?
- A)Loss-of-function mutation in LDL receptor geneGABARITO
- B)Gain-of-function mutation in PCSK9
- C)Deficiency of lipoprotein lipase
- D)Mutation in cholesterol 7-alpha-hydroxylase
- E)Deficiency of apolipoprotein B-100
Explicação
This patient has heterozygous familial hypercholesterolemia (FH) caused by LDL receptor defects. The classic triad of premature CAD, xanthomas, and corneal arcus with markedly elevated LDL is pathognomonic. LDL receptors mediate hepatic uptake of LDL particles... Ver explicação completa e trilha adaptativa →