Neurodegeneration in D-bifunctional protein deficiency: diagnostic clues and natural history using serial magnetic resonance imaging.

We report serial neurodegenerative changes on neuroimaging in a rare peroxisomal disease called D-bifunctional protein deficiency. The pattern of posterior to anterior demyelination with white matter disease resembles X-linked adrenoleukodystrophy. We feel this case is important to (1) highlight that D-bifunctional protein deficiency should be considered in cases where the neuroimaging resembles X-linked adrenoleukodystrophy, (2) to show different stages of progression to help identify this disease using neuroimaging in children, and (3) to show that neuroimaging suggesting a leukodystrophy can warrant peroxisomal beta-oxidation studies in skin fibroblasts even when plasma very long chain fatty acids are normal.