Creutzfeldt-Jakob Disease — Periodic Sharp-Wave Complexes

A 68-year-old woman presents with a 4-month history of rapidly progressive cognitive decline, myoclonic jerks triggered by startle, and gait ataxia. MRI brain shows cortical ribboning on DWI sequences in bilateral parietal cortex and hyperintensity in the caudate and putamen. CSF analysis is positive for RT-QuIC and 14-3-3 protein. The EEG recording marked **B** demonstrates generalized periodic sharp-wave complexes at approximately 1 Hz, time-locked to the myoclonic jerks. Which of the following is the most likely diagnosis?