A 7-year-old boy presents with declining school performance and progressive gait instability over 6 months. Vital signs show BP 108/65, HR 88, RR 20, temp 37°C, SpO2 98%. Examination reveals hyperpigmentation, lower extremity spasticity, and hyperreflexia; no fever noted. MRI demonstrates symmetric demyelination of parieto-occipital white matter. Plasma very-long-chain fatty acid levels are elevated. Accumulation of which substance most likely explains this leukodystrophy?
- A)Homogentisic acid
- B)Very long chain fatty acidsGABARITO
- C)Galactocerebroside
- D)Branched chain amino acids
- E)Methylmalonic acid
Explicação
X linked adrenoleukodystrophy is caused by impaired peroxisomal beta oxidation, leading to accumulation of very long chain fatty acids. These lipids damage myelin and the adrenal cortex, causing neurologic decline and adrenal insufficiency. The boy with spasti... Ver explicação completa e trilha adaptativa →