Severe panencephalic Pick's disease with Alzheimer's disease-like neuropil threads and synaptophysin immunoreactivity.

We report a case of a 69-year-old woman with an 11-year history of progressive dementia, who was found at autopsy to have classic Pick's disease pathology, as well as extensive paired helical filament -- immunoreactive neurities, with few Alzheimer's disease (AD)-like neurofibrillary tangles and no senile plaques. Both Pick bodies and neuritic degeneration were extensive in the neocortex and hippocampal complex. In addition, synaptophysin immunostaining of the hippocampal complex showed a bilaminar pattern of immunoreactivity in the outer molecular layer as previously described in AD.