Abnormal Lipopigments and Lysosomal Residual Bodies in Metachromatic Leukodystrophy

Ultrastructurally, metachromatic leukodystrophy (MLD) is marked by characteristic features such as herringbone, prismatic and tufaceous patterns which are typically encountered within oligodendrocytes of the central nervous system (CNS) and in Schwann cells (PNS). These patterns can be documented in late infantile, juvenile, and adult forms. In the latter, aging of the ailing individual adds another component, the accumulation of lipopigments which are marked by an opaque supposedly lipid droplet and a granular component. While MLD-specific lysosomal residual bodies occur in myelinforming cells, lipopigments accrue in neurons and to a lesser degree in astrocytes. MLD represents a unique exa…