Metabolism USMLE Step 1 Practice Question
A 2-year-old male presents with developmental delay, hepatosplenomegaly, and progressive neurologic decline. Vital signs show HR 110 bpm, RR 24/min, BP 95/60 mmHg, and temperature 37.2°C. Bone marrow biopsy reveals characteristic foam cells. Laboratory studies demonstrate elevated chitotriosidase levels and decreased acid sphingomyelinase activity. The child has no fever or infectious symptoms. He deteriorated progressively despite supportive care and died at age 3. Which metabolic process was most likely deficient in this patient?
Answer choices
- AMitochondrial fatty acid β-oxidation
- BLysosomal glycolipid metabolismCorrect answer
- CAromatic amino acid metabolism
- DHepatic glycogen metabolism
- EPeroxisomal fatty acid α-oxidation
- FLysosomal protein degradation
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