[Detection of brain MRI abnormalities before symptom onset in case of Creutzfeldt-Jakob disease with compound heterozygous PRNP mutation (V180I/M232R)].

In an 81-year-old man, brain diffusion-weighted MRI revealed punctate high-intensity lesions in the bilateral frontal cortex. Three months later, these lesions had extended into the cerebral cortices. Six months after the original MRI, the patient developed cognitive decline. Clinically, he appeared to have Creutzfeldt-Jakob disease (CJD) based on brain MRI and cerebrospinal fluid examination findings. We identified a compound heterozygous mutation (V180I/M232R) in PRNP and diagnosed him with genetic CJD. This case of CJD with a compound heterozygous PRNP mutation had a relatively old onset, slowly progressive course, and low frequency of periodic synchronous discharges. Additionally, we detected CJD-associated brain MRI abnormalities before symptom onset. Reports of presymptomatic CJD such as the present case are important for the development of new therapeutic agents for CJD.