Over 6 months, he experienced progressive behavioral symptoms and worsening memory. Initial MOCA score 23/30. Neurological examination and brain MRI were normal. Blood work including TSH, RPR, CBC, CMP, and B12 were unrevealing. Formal neurocognitive assessment revealed deficiencies in executive functioning and memory. He had progressive cognitive decline and developed gait instability. After multiple falls, he was admitted to the hospital to expedite work-up. His examination demonstrated truncal and appendicular ataxia. Repeat brain MRI was unremarkable. EEG showed generalized slowing. Lumbar puncture was performed with normal WBC, RBC, protein, and glucose. JC virus antibody in blood and CSF were negative. Paraneoplastic antibodies and anti-thyroid antibodies were negative. CSF 14-3-3 protein and RT-QuIC were positive. After 2 months, the patient was readmitted for progressive neurologic deterioration. Examination revealed encephalopathy, dysarthria, hyperreflexia with clonus, and prominent ataxia; MOCA was 16. He developed aspiration pneumonia and was transitioned to hospice care. He died few weeks later. Brain autopsy was diagnostic of CJD.