A progressive neurodegenerative disorder with cortical spongiform change and white matter damage presenting with pseudobulbar palsy

An autopsy case of spongiform encephalopathy with severe white matter degeneration, beginning with slowly progressive pseudobulbar palsy was reported. A 58-year-old man with no family history of neurologic disease noticed speech disturbance at age 38, which gradually deteriorated. By the age of 41, he became totally aphonic, but he could write and understand the meaning of writing. At age 42, he showed pseudobulbar palsy. At age 43, he gradually developed parkinsonism and generalized hyper-reflexia. At age 46, he showed dementia, aphonia, rigidity, generalized hyper-reflexia, left grasping, and quadriplegia in flexion. He died of respiratory failure at age 58, in the state of akinetic mutism, 20 years after the onset of the symptoms. Neuropathologically, the brain showed marked diffuse atrophy. Microscopic examination revealed spongiform encephalopathy with severe neuronal loss and profound white matter degeneration throughout the cerebrum. This case was difficult to categorize in any known neurodegenerative disease, both clinically and neuropathologically, suggesting a new entity of neurodegenerative disease.