An atypical case of sporadic Creutzfeldt-Jakob disease with Parkinson's disease.

We report here an autopsy case of a 64-year-old female with slowly progressive dementia and parkinsonism in a 4-year-long clinical course. Post-mortem examination revealed a severely atrophic brain with spongiform degeneration, neuronal loss and gliosis in the gray matter. Many prion protein plaque deposits were present in the occipital lobe, amygdala and cerebellum. Additionally, Lewy bodies were observed in the brainstem. Prion protein gene analysis of the patient revealed polymorphism at the codon-129 valine heterozygote. This genotype is known to sometimes accompany a missense mutation of the gene in uncommon hereditary prion diseases, but no mutation was found in the open reading frame. Thus, it might be suggested that this case showed simultaneously the features of both sporadic Creutzfeldt-Jakob disease (CJD) with codon-129 valine and Parkinson's disease. However, the predisposing factors for contracting both diseases simultaneously remain to be determined, because the incidence of Parkinson's disease accompanied by CJD is very low.