A 73-year-old Japanese woman showed slowly progressive aphasia, apraxia and dementia. She had no family history of prion disease or dementia. One year later she showed parkinsonism and corticobasal degeneration was initially suspected. On MRI, the left temporal neocortex seemed swollen on T2-weighted images in the initial stage, and a later high-signal intensity region was observed in the cerebral cortex in diffusion-weighted images. The patient developed myoclonus and an akinetic mutism state 15 months and 22 months after onset, respectively. Consecutive electroencephalography revealed no periodic sharp-wave complexes. Prion protein (PrP) gene analysis revealed a valine to isoleucine point mutation at codon 180, and methionine homozygosity at codon 129. This patient's clinical symptoms and disease course were atypical for Creutzfeldt-Jakob disease (CJD), and a stable state with nasal tube-feeding lasted several years. She died of respiratory failure at the age of 81, 102 months after the onset. Autopsy revealed widespread spongiform degeneration with weak synaptic-type PrP deposition, confirming the diagnosis of genetic CJD. Neurons in the cerebral cortex were relatively preserved in number and hypertrophic astrocytosis was generally moderate for such long-term disease, but cerebral white matter showed diffuse severe myelin pallor with tissue rarefaction suggestive of panencephalopatic-type pathology. The cerebellar cortex was relatively well preserved with observation of mild spongiform change in the molecular layer, moderate neuron loss in the Purkinje neuron layer, and scattered small plaque-like PrP deposition. Western blot analysis of protease-resistant PrP showed a characteristic pattern without a diglycoform band. V180I CJD is an interesting form of genetic CJD with regards to the clinicopathologic, molecular and genetic findings.
© 2011 Japanese Society of Neuropathology.