Features of the different forms of Creutzfeldt-Jakob disease (CJD).
| Form of CJD . | Distribution . | Age . | Duration of illness . | Clinical features . |
|---|---|---|---|---|
| Sporadic CJD | Worldwide | 60–80 | Median 4 months; rarely greater than 2 years | Rapidly progressive dementia Impaired movement Myoclonus |
| Variant CJD | Predominantly UK | Median age 27 (range 12–74) | Median 14 months (range 6–40) | Early psychiatric symptoms Unpleasant sensory symptoms Late dementia |
| Familial (genetic) CJD | Worldwide | 30–50 | Variable; may be up to 5 years | Varies with underlying mutation; may resemble sporadic CJD, or a progressive cerebellar ataxia |
| Iatrogenic CJD | Worldwide | Any | 2–18 months, occasionally some years | Depends upon route of infection. Intramuscular route: progressive cerebellar ataxia Neurological route: rapidly progressive dementia |
| Form of CJD . | Distribution . | Age . | Duration of illness . | Clinical features . |
|---|---|---|---|---|
| Sporadic CJD | Worldwide | 60–80 | Median 4 months; rarely greater than 2 years | Rapidly progressive dementia Impaired movement Myoclonus |
| Variant CJD | Predominantly UK | Median age 27 (range 12–74) | Median 14 months (range 6–40) | Early psychiatric symptoms Unpleasant sensory symptoms Late dementia |
| Familial (genetic) CJD | Worldwide | 30–50 | Variable; may be up to 5 years | Varies with underlying mutation; may resemble sporadic CJD, or a progressive cerebellar ataxia |
| Iatrogenic CJD | Worldwide | Any | 2–18 months, occasionally some years | Depends upon route of infection. Intramuscular route: progressive cerebellar ataxia Neurological route: rapidly progressive dementia |