Metabolism USMLE Step 1 Practice Question
A 2-week-old male presents with projectile vomiting after each milk-based formula feeding and failure to gain weight. Vital signs show HR 128/min, RR 32/min, temperature 37.2°C. Serum galactose is markedly elevated at 18 mg/dL (normal <20 mg/dL in newborns, but symptomatic at this level). Urine reducing substances are present. Biochemical testing confirms severe galactose-1-phosphate uridyltransferase deficiency. No hepatomegaly is currently appreciated. If left untreated, what is the most likely long-term outcome?
Answer choices
- ABenign disease except for cataract formation
- BDeath in infancyCorrect answer
- CChronic emphysema appearing in early adulthood
- DChronic renal failure appearing in adolescence
- EGastrointestinal symptoms that remit with puberty
- FProgressive intellectual disability and cirrhosis with survival into adulthood
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