Demyelinating Diseases USMLE Step 1 Practice Question
An 8-year-old boy presents with declining school performance, progressive spasticity, and hyperpigmentation over 6 months. He experiences recurrent vomiting and exhibits adducted thumbs. Vital signs: BP 92/58 mmHg, HR 102 bpm, RR 18/min, temp 37.2°C. Laboratory studies reveal primary adrenal insufficiency with cortisol 3 mcg/dL. Plasma very long chain fatty acids are markedly elevated. Brain MRI shows cerebral white matter involvement. No hepatosplenomegaly is noted. Which of the following is the most likely diagnosis?
Answer choices
- AKrabbe disease
- BMetachromatic leukodystrophy
- CX linked adrenoleukodystrophyCorrect answer
- DMultiple sclerosis
- ESpinal muscular atrophy
- FPelizaeus-Merzbacher disease from PLP1 gene mutation
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