A Rare Case of Creutzfeldt-Jakob Disease Presenting with Amyotrophic Lateral Sclerosis

Creutzfeldt-Jakob disease (CJD) is a rare, fatal neurodegenerative condition with rapid dementia and motor issues. A 76-year-old woman developed progressive quadriparesis over three years, beginning in the lower limbs and extending to the upper limbs. Clinical assessment revealed upper and lower motor neuron involvement, including spasticity, hyperreflexia, bilateral Babinskis sign, and fasciculations. Brain magnetic resonance imaging revealed bilateral thalamic lesions, indicating possible transmissible spongiform encephalopathy. Neuropsychological testing revealed fronto-subcortical syndrome with mild cognitive impairment. Neuropathology confirmed CJD with subcortical and motor cortex involvement, early-stage amyotrophic lateral sclerosis, argyrophilic grain disease (stage III), and moderate Alzheimer's changes (A2B1C2). Cognitive symptoms were primarily attributed to the CJD. This case demonstrates the diagnostic challenges of atypical CJD presentations mimicking amyotrophic lateral sclerosis, highlighting the importance of neuroimaging, clinical, and neuropathological correlation in elderly patients with motor and cognitive decline.