Ultrastructure of Brain and Nerve Biopsy Tissue in Wilson Disease

Abstract

A 14-year-old girl with psychomotor deterioration developed Wilson disease. Mild atrophy of the small hand muscles was an unusual feature. A cerebral cortex biopsy specimen disclosed exuberant spheroid production, chromatolytic changes, myelin and axonal degeneration, alterations of capillary basal lamina, Hirano bodies, Alzheimer type protoplasmic astrocytosis, and many neuropil-based nonneuronal elements ("M" cells) of heterogeneous derivation distinct from astrocytes and normal oligodendrocytes. On reviewing neuroglia cell changes in light of present findings, the following conclusions become obvious: Alzheimer type II astrocytosis is true cellular hyperplasia of a class of reactive protoplasmic astrocytes with variable cytologic features. Alzheimer type I astrocytes most probably do not exist; the designation should be dropped. M cells play an important role in the cytopathology of Wilson disease; some forms may generate the so-called Alzheimer type I astrocyte.