Metabolism USMLE Step 1 Practice Question
A 12-year-old boy with short stature presents with fasting hypoglycemia (45 mg/dL), hepatomegaly, and a bleeding diathesis. Vital signs show BP 95/60, HR 102, RR 18, temp 37°C, SpO2 98%. Laboratory studies reveal lactate 8 mmol/L (normal <2), triglycerides 650 mg/dL, cholesterol 280 mg/dL, and uric acid 9 mg/dL. Renal ultrasound shows bilateral kidney enlargement. He denies acetaminophen use. This patient most likely has a deficiency of which of the following metabolic processes?
Answer choices
- AGlycogen metabolismCorrect answer
- BBranched-chain amino acid metabolism
- CLipoprotein metabolism
- DNucleotide metabolism
- ELysosomal glycolipid metabolism
- FDebranching enzyme deficiency impairing limit dextrin mobilization from glycogen
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.