Table 2.

Characteristics of AHDS to classify it as a genetic leukoencephalopathy (gLE) vs. a leukodystrophy.

Traits in favor of a gLE	Traits in favor of a leukodystrophy
Slow but gradual progression in brain myelination	Persistent hypomyelinated features in some patients
WM abnormalities subordinate to neuronal problems	WM micro-abnormalities found at later age
Neuronal cells are main cause of pathology	Endothelial and glial cells also affected
Non-CNS organs affected	No obvious neurological damage on MRI

CNS, central nervous system; MRI, magnetic resonance imaging; WM, white matter.