Neuroaxonal Dystrophy Due to Lysosomal α-N-Acetylgalactosaminidase Deficiency

Abstract

AMONG the inherited neurologic diseases, the neuroaxonal dystrophies constitute a group of neurodegenerative disorders characterized by a common axonal lesion.1 These disorders include the infantile (Seitelberger's disease), late-infantile, and juvenile forms of neuroaxonal dystrophy, neuroaxonal leukodystrophy, and Hallervorden–Spatz syndrome, which can be of late-infantile, juvenile, or adult onset. The morphologic hallmark of these disorders is the presence of swellings, or "spheroids," in the terminal endings or the distal portions of axons in the central nervous system, or both. Ultrastructurally, such axonal swellings contain densely packed layers of smooth endoplasmic reticulum and other membranous arrays, among which mitochondria, lysosomes, other organelles, . . .