Early on neurons and axons may be spared. Inflammation not prominent. Occasional perivascular cuffing. Bizarre, almost neoplastic-appearing astrocytes without increased cell density. In major lesional sites, oligodendrocytes are largely missing or absent as are inclusional cells.
Macrophage infiltrate common in area of white matter destruction.
Clinical Features Symptoms and Signs 1. Insidious onset occurring at any time during course of underlying disease. Mental deterioration, dementia, behavioural abnormalities. CT usually shows multifocal white matter lesions adjacent to the grey-white border. Generally fatal in 3 to 20 months.