Table 1.
Diagnosis of sporadic CJD—comparison of WHO 1998 criteria with suggested updated criteria combining the 2009 MRI-CJD consortium criteria with the University of California, San Francisco (UCSF) 2010 MRI criteria (adapted from Zerr et al and Vitali et al)2 5 7 8
| WHO 1998 criteria | Suggested updated criteria |
|---|---|
| Group I | Group I (clinical signs) |
| Rapidly progressive dementia (<2 years) | Rapidly progressive dementia (<2 years) |
| Group II (symptoms) | Myoclonus |
| Myoclonus | Visual and cerebellar disturbance |
| Visual and cerebellar disturbance | Pyramidal and extrapyramidal features |
| Pyramidal and extrapyramidal features | Akinetic mutism |
| Akinetic mutism | Group II (tests)* |
| Group III (tests) | Typical EEG with periodic sharp wave complexes (PSWCs) |
| Typical EEG with PSWCs | 14-3-3 and/or tau proteins present in ideally blood free cerebrospinal fluid |
| 14-3-3 protein present in cerebrospinal fluid | MRI asymmetric hyperintensity, more obvious on DWI than on FLAIR, with related hypointensity on ADC map in at least three cortical non-contiguous gyri and/or in the striatum (caudate and rostral part of the putamen)† |
| Possible CJD | |
| Criterion I+at least two criteria from group II+None from group III | At least two criteria of group I+duration less than 2 years |
| Probable CJD | |
| Possible diagnosis+at least one criteria from group III | Possible CJD+at least one from II |
| Definite CJD | |
| Neuropathology and/or immunochemistry | |
*MRI should be performed first whenever affordable, providing that it is the best performing diagnostic test.
†Clues for the interpretation of MRI findings:
(a) In sCJD, there is an anteroposterior gradient of the striatal hyperintensity with relative sparing of posterior putamen;
(b) Isolated limbic hyperintensity either on FLAIR or DWI almost rules out the diagnosis of sCJD;
(c) Grey matter hyperintensities can sometimes be found only on DWI sequences and not on FLAIR;
(d) High signal abnormalities in neocortical areas with sparing of the precentral gyrus are supportive for a sCJD cortical involvement;
(e) A normal MRI rules out the diagnosis of sCJD;
(f) In prolonged courses of sCJD (>1 year), brain MRI might show significant atrophy with loss of DWI hyperintensity, particularly in areas previously with restricted diffusion.9 10
ADC, apparent diffusion coefficient; CJD, Creutzfeldt-Jacob disease; DWI, diffusion-weighted imaging; FLAIR, fluid attenuation inversion recovery; sCJD, sporadic Creutzfeldt-Jacob disease.