Metabolism USMLE Step 1 Practice Question
A 57-year-old male with poorly controlled type 1 diabetes presents with progressive vision loss. Vitals: BP 148/92 mmHg, HR 88/min, RR 16/min, Temp 37.2°C. Ophthalmoscopic examination reveals macular edema, retinal thickening, and hard yellow-white lipid exudates. Laboratory studies show fasting glucose 285 mg/dL, triglycerides 380 mg/dL, and LDL cholesterol 165 mg/dL; urinalysis is negative for ketones. Which metabolic pathway abnormality in type 1 diabetes contributes most to this hyperlipidemia and retinal lipid deposition?
Answer choices
- AGlucose conversion to sorbitol in the lens
- BOveractive GLUT2 in liver
- COveractive hormone-sensitive lipaseCorrect answer
- DOveractive GLUT4 in adipose
- EOveractive lipoprotein lipase
- FDecreased lipoprotein lipase activity in peripheral tissues
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.