Introduction to Prions (3) Flashcards
What prion group makes up 80% of prion diseases?
sporadic CJD
What demographic does sporadic CJD effects the most?
mean age of onset is 60 years
beyond 60 years
How quickly can a patient die after sporadic CJD?
4-5 MONTHS
In what state will a patient die with sporadic CJD?
Death in an akinetic, mute state after a median of 4-5 months
What demographic does vCJD effect the most?
Patients with vCJD are much younger than those with sporadic CJD (death occurs at a median of 29 years).
What are the initial symptoms of a patient with vCJD?
60% of patients present with psychiatric symptoms such as anxiety, insomnia or withdrawal.
What are the later, more clear cut signs a patient has vCJD?
4, 6 & 14 months
- After 4 months there are clear cut neurological signs such as gait disturbance, slurred speech and tremor.
- Involuntary movements, cognitive impairment and ataxia manifest after 6 months.
- Illness duration is longer than with sporadic CJD, with a median of 14 months.
What has a longer illness duration sporadic of variant CJD?
vCJD lasts longer
Many people are exposed to vCJD (contaminated beef products), why are there relatively low numbers than that predicted?
host genotype susceptibility
What are he 2 amino acids which could occur at codon 129 of the prion protein?
M or V
What are the 3 combinations of amino acids M and V?
VV (12%)
MM (37%)
MV (51%)
What combination of M and V do all individuals with vCJD have?
Methionine homozygotes MM
predisposed to being susceptible to vCJD
Compare a CJD and control brain?
CJD is atrophic (smaller) and lager vacuoles
What tests would you use to diagnose CJD?
DIFFICULT – definitive diagnosis at post mortem.
Ante-mortem - based on clinical neurological signs.
CSF (best) looking for nuronal proetin 14-3-3
MRI
EEG
Tonsil biopsy
PRNP gene analysis
How could you manage CJD in patients, experimental drugs?
antimicrobials
PRN100- monoclonal antibody and binds to cellular prion protein (difficult to make)
