Multimodal neuroimaging in a case of familial (G114V) juvenile Creutzfeldt–Jakob disease presenting with parkinsonism

Creutzfeldt - Jakob disease (CJD) is a subacute spongiform encephalopathy characterised by rapidly progressive dementia and is difficult to diagnose antemortem. We present the case of a 21-year-old woman with a family history of early-onset neurological disease of unclear aetiology. She had a 2-year history of rapidly progressive cognitive decline, cogwheel rigidity in all four limbs and ataxia. After initial evaluation, she was referred to the nuclear medicine centre for ^99mTc-TRODAT SPECT, which revealed mildly reduced uptake of the presynaptic radiotracer in the right caudate and left putamen, consistent with dopaminergic dysfunction. ^99mTc-ECD perfusion SPECT showed widespread cortical hypoperfusion, including involvement of the right thalamus and cerebellum, indicative of global neuronal dysfunction. MRI revealed high signal intensity on diffusion-weighted imaging, and ¹¹C-deuterium-L-deprenyl PET/CT demonstrated reactive astrocytosis. The final diagnosis was probable CJD according to the Centers for Disease Control and Prevention criteria. Follow-up revealed that the patient belonged to a family carrying a missense mutation in the PRNP gene (G114V). These findings describe the neuroimaging phenotype of an early-onset familial CJD and highlight the role of multimodal brain imaging in both the diagnosis and pathophysiological understanding of movement disorders in this condition.