Diagnostic Criteria

Definite Variant CJD

Neuropathologic examination of brain tissue is required to confirm a diagnosis of variant CJD. The following confirmatory features should be present.

1. Numerous widespread kuru-type amyloid plaques surrounded by vacuoles in both the cerebellum and cerebrum – florid plaques.
2. Spongiform change and extensive prion protein deposition shown by immunohistochemistry throughout the cerebellum and cerebrum.

Suspected Variant CJD

1. Current age or age at death <55 years (a brain autopsy is recommended, however, for all physician-diagnosed CJD cases).
2. Psychiatric symptoms at illness onset and/or persistent painful sensory symptoms (frank pain and/or dysesthesia).
3. Dementia, and development ≥4 months after illness onset of at least two of the following five neurologic signs: poor coordination, myoclonus, chorea, hyperreflexia, or visual signs. (If persistent painful sensory symptoms exist, ≥4 months delay in the development of the neurologic signs is not required).
4. A normal or an abnormal EEG, but not the diagnostic EEG changes often seen in classic CJD.
5. Duration of illness of over 6 months.
6. Routine investigations of the patient do not suggest an alternative, non-CJD diagnosis.
7. No history of receipt of cadaveric human pituitary growth hormone or a dura mater graft.
8. No history of CJD in a first degree relative or prion protein gene mutation in the patient.