Alzheimer neurofibrillary tangles in diseases other than senile and presenile dementia.

A brief description is given of neurofibrillary changes of the paired helical filament type in a variety of chronic neurological diseases. These include subacute sclerosing panencephalitis, lead encephalopathy, tuberous sclerosis, Down syndrome, Hallervorden-Spatz disease, and lipofuscinosis. In these conditions, with the exception of Hallervorden-Spatz disease neurofibrillary changes were previously recognized but paired helical filaments were identified only in some cases. Moreover, in the present series, the age of patients at death was often younger than in previously recorded cases.