Intranuclear inclusion bodies in an elderly demented woman: a form of intranuclear inclusion body disease.

Intranuclear inclusion body disease (INIBD) is a rare neuropathological entity characterized by eosinophilic intranuclear bodies in neurons and/or glia. While this disease generally occurs in children, in whom it presents as a multiple systems degeneration, a few adult cases are also described. Only 4 previously reported adult cases have had an associated dementia and all of these patients had additional significant neurological abnormalities. We report a 72-year-old woman with primary degenerative dementia in whom intranuclear inclusion bodies (INIB) were a major neuropathologic finding. The INIB were most easily found in astrocytes of Alzheimer II type, which had proliferated in the cortex and white matter. Occasional neurons were affected. The inclusions consisted of 13 nm diameter filaments associated with amorphous electron-dense material, arranged in a random pattern without lattice formation. They did not stain with antibodies against all 3 neurofilament subunits, glial fibrillary acidic protein, tau-1 protein, vimentin, keratin or actin. We conclude that INIBD is a rare substrate of primary degenerative dementia in elderly patients.