Metabolism USMLE Step 1 Practice Question
A 4-year-old male is brought to the pediatrician because of gastroenteritis for 3 days, followed by a brief generalized seizure that left him semicomatose. The blood glucose level at admission is 18 mg/dL (0.10 mM) and urine is negative for glucose and ketones, but positive for a variety of organic dicarboxylic acids. Intravenous administration of glucose improves his condition within 10 minutes. Following diagnosis of an enzyme deficiency, his parents are cautioned to make sure he eats frequently. Which of the following is the most likely diagnosis?
Answer choices
- AGlucose-6-phosphatase deficiency
- BOrnithine transcarbamoylase deficiency
- CMitochondrial carbamoyl phosphate synthetase deficiency
- DMedium-chain acyl-CoA dehydrogenase deficiencyCorrect answer
- EHepatic glycogen phosphorylase deficiency
- FLong-chain acyl-CoA dehydrogenase deficiency
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