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.
  1. If a patient has the typical bilateral pulvinar high signal on MRI scan, a suspected diagnosis of variant CJD requires the presence of a progressive neuropsychiatric disorder, d, e, f and g of the above criteria, and four of the following five criteria: 1) early psychiatric symptoms (anxiety, apathy, delusions, depression, withdrawal); 2) persistent painful sensory symptoms (frank pain and/or dysesthesia); 3) ataxia; 4) myoclonus or chorea or dystonia; and 5) dementia.
  2. A history of possible exposure to bovine spongiform encephalopathy (BSE) such as residence or travel to a BSE-affected country after 1980 increases the index of suspicion for a variant CJD diagnosis.