Table 3.

Red flags: clinical features that might indicate a CJD mimic

Feature	Indicates
Fever	Infections, lymphoma
Seizures	Implies less likely to be CJD, infective and immune encephalitis, neoplasia, many other mimics
Hyponatraemia	VGKC encephalitis
Facial movement disorder	NMDA-R encephalitis, CNS Whipple’s disease
Modest progression	Implies less likely to be CJD, more likely to be a common neurodegenerative disorder
CSF pleocytosis	Infections, lymphoma, inflammatory, neoplastic
Contrast-enhancing lesions	Infections, lymphoma, inflammatory, neoplastic
MRI hyperintensities on T2-weighted imaging outside the striatum, thalamus and cortex	Vascular diseases, lymphoma, progressive multifocal leukoencephalopathy, encephalitis, extrapontine myelinolysis, others

CJD, Creutzfeldt–Jakob disease; CNS, central nervous system; CSF, cerebrospinal fluid; NMDA-R, N-methyl-D-aspartate; VGKC, voltage-gated potassium channel.