[Frontoparietal dementia and parkinsonism: autopsy report of a sporadic case]

We report a 75-year-old man who presented with parkinsonism, dementia and vertical gaze palsy. Postmortem examination revealed frontoparietal atrophy and nigral depigmentation. The temporal lobe was well preserved. Histologically, the affected cerebral cortex showed vacuolation and neuronal loss in layers 2 and 3. The substantia nigra and globus pallidus were also affected. There was gliosis in the thalamic medial nuclei and midbrain tegmentum. Neither ballooned neurons nor taupositive, argyrophilic inclusions could be found. Moreover, there was no Alzheimer pathology manifested by senile plaques and neurofibrillary tangles. In fact, the clinical and pathological features of the present case were consistent with those observed previously in two other cases reported elsewhere (Kawasaki et al. Acta Neuropathol 91: 140, 1996). In these cases, corticobasal degeneration (CBD) and frontotemporal dementia (FTD) were considered to be the principal entities in the differential diagnosis. However, we believe that these three cases, including the present one, were not examples of CBD or FTD, since neither ballooned neurons nor tau abnormalities were present, and the precentral gyrus was the area most severely involved, the temporal lobes being obviously spared. Therefore we considered that they might represent a hitherto unrecognized new disease entity.