Metabolism USMLE Step 1 Practice Question
A 5-year-old boy presents with recurrent episodes of severe abdominal pain and eruptive yellow papules over extensor surfaces. Vital signs show BP 110/68 mmHg, HR 98/min, RR 20/min, temperature 37°C. Physical examination reveals lipemia retinalis and hepatosplenomegaly. Laboratory studies show fasting triglycerides of 1,200 mg/dL (normal <150), total cholesterol 350 mg/dL, and normal LDL levels. No lipemic serum is noted on repeat sampling. Which of the following proteins is most likely deficient?
Answer choices
- AApolipoprotein E
- BApolipoprotein CII or lipoprotein lipaseCorrect answer
- CApolipoprotein B100
- DMicrosomal triglyceride transfer protein
- ELDL receptor
- FApolipoprotein A-V
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