Dementia/parkinsonism With Non-Alzheimer Amyloid Plaques

Rosenberg et al. (1989) described a family in which 14 persons in 5 generations suffered from severe dementia and parkinsonism. In 2 autopsied members of the family, neuropathologic correlations consisted of extracellular hyaline eosinophilic, congophilic amyloid plaques in the cerebral cortex, basal ganglia, thalamus, and substantia nigra, in descending order of frequency, as well as atrophy and gliosis of the basal ganglia and substantia nigra. The extracellular plaque did not stain with antibody raised against the prion protein or with 2 separate anti-amyloid A4 antibodies. Although no instance of male-to-male transmission was identified in the family, the inheritance was thought to be autosomal dominant. Both Alzheimer disease and Gerstmann-Straussler syndrome could be excluded by the properties of the amyloid.