[Virus-like inclusions in the cells of the central nervous system in amyotrophic lateral sclerosis].

Electron microscopic examination of the frontal cortex of a patient with amyotrophic lateral sclerosis (ALS) with 14-year prolongation of life by artificial ventilation of the lungs revealed heretofore undescribed cytoplasmic virus-like inclusions in neurons and glial cells as well as changes in the granular endoplasmic reticulum in astrocytes consisting of large accumulations of ribosomes in which regular arrays were frequently observed. The discovered inclusions were not similar to any identified viral inclusions but were similar to virus-like particles found in the muscle in ALS and viral inclusions in experimental poliomyelitis. The role of the observed inclusions and their etiological importance remain obscure.