Human prion disease is divided into three broad classes: idiopathic, genetic and acquired, reflecting different causation with resulting variations in clinical and neuropathological features. There are significant differences in clinical presentation both between and within these three groups, but all are progressive, fatal brain diseases with dementia, cerebellar ataxia and involuntary movements being particularly prominent features. Absolutely definite diagnosis requires neuropathological analysis of brain tissue (via cerebral biopsy in life or at autopsy) but there are established clinical diagnostic criteria and a variety of supportive investigations including abnormalities in the EEG, cerebral MRI, PRNP genetic analysis and CSF protein analysis. The precise results of these supportive investigations and their diagnostic utility vary somewhat depending on the type of prion disease. For example, EEG periodic discharges are a characteristic finding in sporadic but not variant CJD, for variant CJD, tonsil biopsy is an additional test and, in genetic prion disease, blood testing is possible for pathogenic PRNP mutations.

prion diseases, clinical aspects of prion diseases, Creutzfeldt-Jakob disease, variant Creutzfeldt-Jakob disease, iatrogenic Creutzfeldt-Jakob disease