Parkinsonism, dementia and vertical gaze palsy in a Guamanian with atypical neuroglial degeneration

A 58-year-old Chamorro female patient, who died in 1993, was examined clinicopathologically. At the age of 51, she suffered from hemiparkinsonism, then bradykinesia, rigidity without tremor, and dementia. Extrapyramidal symptoms developed, and at the age of 57, vertical gaze palsy was noted. The clinical diagnosis was parkinsonism-dementia complex (PDC) with vertical gaze palsy. The brain showed atrophy in the frontal and temporal lobes, and the atrophy was accentuated in the dentate gyrus, Ammon's horn and parahippocampal gyrus. The basal ganglia, thalamus and midbrain were moderately atrophic. The substantia nigra and locus ceruleus were completely depigmented. Numerous neurofibrillary tangles (NFTs) were seen in the subiculum and amygdaloid nucleus. Many NFTs were evident in the parahippocampal gyrus, lateral occipitotemporal gyrus, insula, Sommer sector, basal nucleus of Meynert, lateral nucleus of the thalamus, subthalamic nucleus and brain stem, and several were observed in the globus pallidus and hypothalamus, The Sommer sector, substantia nigra, locus ceruleus and basal nucleus of Meynert showed severe loss of neurons, and a moderate loss of neurons was exhibited by the globus pallidus. These findings were apparently consistent with those associated with PDC. However, in this patient, severe neuronal loss was seen in the subthalamic nucleus and lateral nucleus of the thalamus, and grumose degeneration, which has not previously been reported in PDC, was seen in the dentate nucleus, In addition, many tufted astrocytes, which have been reported to occur in progressive supranuclear palsy (PSP) and postencephalitic parkinsonism, but scarcely observed in PDC, were present. Furthermore, astrocytic plaques, which have been considered as a specific finding of corticobasal degeneration (CBD), were observed in the cerebral cortex. On the other hand, granular hazy astrocytic inclusions, previously reported to occur in PDC, were not seen. Chromatolytic neurons were not observed. The question thus arises as to whether it is appropriate to consider this patient as having suffered from a combination of PDC, PSP and CBD. From the view points of absence of granular hazy astrocytic inclusions and chromatolytic neurons, and of tufted astrocytes in the neostriatum, it is conceivable that this patient is a case of a new disease entity.