Clinical features of variant Creutzfeldt-Jakob disease

The possibility that a new form of human prion disease, variant Creutzfeldt-Jakob disease (vCJD) had occurred in the UK was first raised by the identification of a small number of cases with unusual clinical characteristics. Atypical features included a young age at death, a predominantly psychiatric presentation, a relatively extended duration of illness and the absence of the 'typical' periodic electroencephalogram seen in sporadic CJD. Diagnostic criteria for vCJD have now been formulated and partially validated. Magnetic resonance imaging of the brain shows high signal in the posterior thalamus in the great majority of cases and all tested cases to date have been methionine homozygous at codon 129 of the prion protein gene (PRNP). There is a need to try and improve early diagnosis, particularly if effective treatments are developed.