Creutzfeldt-Jakob disease
Creutzfeldt-Jakob disease (CJD) is rapidly progressive neurological condition caused by prion proteins. These proteins induce the formation of amyloid folds resulting in tightly packed beta-pleated sheets resistant to proteases.
Features
Investigation
Sporadic CJD
New variant CJD
Other prion diseases
Features
- dementia (rapid onset)
- myoclonus
Investigation
- CSF is usually normal
- EEG: biphasic, high amplitude sharp waves (only in sporadic CJD)
- MRI: hyperintense signals in the basal ganglia and thalamus
Sporadic CJD
- accounts for 85% of cases
- 10-15% of cases are familial
- mean age of onset is 65 years
New variant CJD
- younger patients (average age of onset = 25 years)
- psychological symptoms such as anxiety, withdrawal and dysphonia are the most common presenting features
- the 'prion protein' is encoded on chromosome 20 - it's role is not yet understood
- methionine homozygosity at codon 129 of the prion protein is a risk factor for developing CJD - all patients who have so far died have had this
- median survival = 13 months
Other prion diseases
- kuru
- fatal familial insomnia
- Gerstmann Straussler-Scheinker disease
