Diagnostic criteria for variant CJD
| *Depression, anxiety, apathy, withdrawal, delusions. | |
| †This includes both frank pain, unpleasant dysaesthesia, or both. | |
| ‡Generalised triphasic complexes at about 1 Hz. | |
| §Spongiform change and extensive prion protein deposition with florid plaques throughout cerebrum and cerebellum. | |
| EEG, electroencephalogram; vCJD, variant Creutzfeldt-Jakob disease. | |
| I | A: Progressive neuropsychiatric disorder |
| B: Duration of illness more than six months | |
| C: Routine investigations do not suggest an alternative diagnosis | |
| D: No history of potential iatrogenic exposure | |
| II | A: Early psychiatric symptoms* |
| B: Persistent painful sensory symptoms† | |
| C: Ataxia | |
| D: Myoclonus, chorea, or dystonia | |
| E: Dementia | |
| III | A: EEG does not show typical appearance of sporadic CJD‡ (or no EEG done) |
| B: Bilateral pulvinar high signal on magnetic resonance imaging | |
| Definite vCJD | IA (progressive neuropsychiatric disorder) and neuropathological confirmation of vCJD§ |
| Probable vCJD | I and 4/5 of II and IIIA and IIIB |
| Possible vCJD | I and 4/5 of II and IIIA |