A 6-year-old boy presents with severe growth retardation, steatorrhea, and progressive neurodegeneration. Vital signs show BP 95/60, HR 102, RR 20, temperature 37.2°C, and SpO2 98% on room air. Laboratory studies reveal markedly elevated very long-chain fatty acids (VLCFAs) at 200 times the upper limit of normal, with normal very long-chain fatty acid β-oxidation. MRI demonstrates extensive cerebral white matter abnormalities. He denies recent infections. Which of the following is the most likely diagnosis?
- A)X-linked adrenoleukodystrophy due to impaired peroxisomal β-oxidation of VLCFAsGABARITO
- B)Zellweger syndrome with global peroxisomal dysfunction
- C)Mitochondrial fatty acid oxidation disorder affecting medium-chain fatty acids
- D)Primary carnitine deficiency affecting all fatty acid oxidation
- E)Niemann-Pick disease type C with impaired cholesterol trafficking
Explicação
X-linked adrenoleukodystrophy (X-ALD) results from mutations in the ABCD1 gene encoding a peroxisomal transporter for very long-chain fatty acids (VLCFAs, >20 carbons). Impaired transport prevents peroxisomal β-oxidation of VLCFAs, causing severe accumulation.... Ver explicação completa e trilha adaptativa →