Sporadic amyotrophic lateral sclerosis with circumscribed temporal atrophy: a report of an autopsy case without dementia and with ubiquitinated intraneuronal inclusions.

This report concerns an autopsy case of amyotrophic lateral sclerosis (ALS) with circumscribed temporal atrophy. The patient was a Japanese woman without hereditary burden who was 71-year-old at the time of death. She developed dysarthria and gait disturbance at age 69, followed by dysphagia. A neurological examination about 1 year 11 months after the onset of the disease revealed absence of character change and of dementia. Neuroradiological examination disclosed circumscribed atrophy of the anterior part of the right temporal lobe. The patient died of respiratory failure 2 years after the disease onset. No respirator administration was performed throughout the clinical course. Macroscopically, neuropathological examination showed circumscribed atrophy of the right first temporal gyrus. Histologically, there was neuronal loss in the cerebral cortex, including the first temporal gyrus, the parahippocampal gyrus, subiculum, amygdala, substantia nigra, brain stem motor nuclei, and anterior horns of the spinal cord, in addition to loss of Betz cells, obvious degeneration of the pyramidal tracts, and the presence of Bunina bodies. Ubiquitin-immunoreactive intraneuronal inclusions were present in the hippocampal dentate granular cells, frontotemporal cortical layer II neurons, and motor neurons in the brain stem and spinal cord. Based on these clinicopathological findings and a review of the literature, we concluded that our case was atypical ALS without dementia, showing temporal lobe atrophy macroscopically, in addition to pathological hallmarks compatible with ALS with dementia. We also note the possibility that there is a forme fruste of ALS with dementia showing no overt dementia clinically.