Metabolism USMLE Step 1 Practice Question
A 4-year-old boy with developmental delay presents with self-injurious behavior, repeatedly striking his head against walls and severely biting his fingertips requiring bandaging. Vital signs: BP 95/60, HR 98, RR 20, Temp 37°C, SpO2 98%. Serum uric acid is elevated at 9.2 mg/dL. He denies recent fever or joint pain. His parents report normal birth history. Elevated blood levels of which of the following would be most diagnostic of this disorder?
Answer choices
- AUric acidCorrect answer
- BDicarboxylic acids
- CAmmonium ion
- DOrotic acid
- EPhenylacetate
- FHypoxanthine
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