Metabolism USMLE Step 1 Practice Question
A 2-month-old male is evaluated for failure to thrive. As the pediatrician is examining the patient, she witnesses a seizure. Physical examination is remarkable for hepatomegaly, a finding later confirmed by CT scan, which also reveals kidney enlargement. Serum chemistries demonstrate severe hypoglycemia, hyperlipidemia, and lactic acidosis. Which of the following enzyme deficiencies best accounts for this clinical presentation?
Answer choices
- AGlucocerebrosidase
- BGlycogen phosphorylase
- CGlucose-6-phosphataseCorrect answer
- DSphingomyelinase
- Eα-1,4-Glucosidase (acid maltase)
- FPhosphorylase kinase
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