Multiple system atrophy.

Multiple system atrophy (MSA) is a degenerative disease of the central nervous system with three components, usually variously expressed: nigrostriatal degeneration (NSD), olivopontocerebellar atrophy (OPCA) and Shy-Drager syndrome of autonomic system dysfunction (SDS). The clinical progression of MSA leads to death in a shorter time than in any of the components occurring separately. A common, and according to some authors, pathognomonic neuropathological finding in MSA cases is the presence of argyrophilic inclusions in the cytoplasm of glial cells, mainly oligodendrocytes, in the structures of the encephalon with most pronounced atrophic changes.