Probable Sporadic Creutzfeldt-Jakob Disease Presenting as Rapidly Progressive Dementia: A Case Report From Georgia.

Creutzfeldt-Jakob disease (CJD) is a rare, fatal prion disorder that commonly presents as rapidly progressive dementia and may initially mimic autoimmune, paraneoplastic, infectious, or metabolic encephalopathies. We report a case of probable sporadic CJD in a 53-year-old man from Georgia who developed approximately one month of progressive gait difficulty, dysarthria, behavioral changes, and memory impairment. Neurological examination revealed hypophonic dysarthric speech, horizontal nystagmus, mild-to-moderate tetraparesis, dystonic hyperkinesia, distal sensory impairment, and severe gait ataxia with astasia-abasia. Brain computed tomography showed no acute intracranial lesion, while magnetic resonance imaging demonstrated restricted diffusion involving the head and body of the left caudate nucleus. Electroencephalography (EEG) demonstrated nonspecific findings. Testing for a defined set of autoimmune and paraneoplastic antibodies was negative, and positron emission tomography showed no evidence of malignancy. Electroneuromyography demonstrated mixed demyelinating and axonal peripheral nerve involvement. Cerebrospinal fluid (CSF) analysis showed no pleocytosis, a mildly elevated protein level, and a positive CSF 14-3-3 protein result, supporting the diagnosis of probable sporadic CJD. Real-time quaking-induced conversion (RT-QuIC) testing was not performed because it was unavailable in the treating clinical setting. Empirical high-dose methylprednisolone produced no meaningful neurological improvement. The patient subsequently progressed to a bedbound, nonverbal state with severe dependence and recurrent respiratory complications. Despite prolonged intensive care, mechanical ventilation, tracheostomy, and broad-spectrum antimicrobial therapy, he died approximately seven months after symptom onset from pneumonia complicated by acute respiratory failure and shock, culminating in cardiac arrest. This case highlights the diagnostic challenges of rapidly progressive dementia and the importance of considering sporadic CJD when cognitive decline is accompanied by cerebellar, pyramidal, extrapyramidal, and peripheral neurological features.