Microbiology 9 - Prion disease Flashcards
Describe some possible symptoms of prion disease
Ataxia UMN weaknesses Nystagmus Limb spasticity Hyperreflexia Paraesthesia Tremor (all neuro symptoms!)
What marker of Creutzfeld Jacob Disease may be identified in CSF?
14-3-3 protein
What is the recognised abnormailty on MRI that is indicative of CJD?
Increased signal in right parietal lobe
What does ‘prion’ stand for?
PRotein-only InfectiOus ageNt.
What is the general pathophysiology of prion diseases?
Rapid neurodegeneration via spongiform vacuolation
Upon which chromosome is prion encoded?
C20
Describe the structure and function of healthy prion
Alpha helical structure - involved in copper binding
What is the structure of pathological prion?
Beta pleated sheet
What is the name given to sporadic prion disease?
Creutzfeld Jacob Disease
What are the 2 types of acquired prion disease currently known about?
- Variant/ iatrogenic CJD (included mad cow BSE)
2. Kuru (Papau New Guinea)
Recall 3 genetic/familial causes of prion disease
- PRNP mutations
- Gertsmann-Strausser-Sheinker syndrome
- Familial fatal insomnia
How does CJD present?
RAPID DEMENTIA with:
- myoclonus
- cortical blindness
- akinetic mutism
- LMN signs
What is the mean age of onset of CJD?
65
How quickly does CJD cause death?
Within 6/12
What is the mean age of presentation of variant CJD/ BSE?
26
What is the mean survival time in variant CJD?
14 months
Recall the typical presentation of variant CJD/ BSE
Dysphonia (hoarseness of voice) Hallucinations Anxiety Paranoia (Psychological symptoms mostly)
What would an MRI show in variant CJD/ BSE?
Positive pulvinar sign (hypersensitivities including the pulvinar thalamic nuclei)
What test is 100% sensitive and specific for variant CJD/ BSE, but useless in sporadic CJD?
Tonsilar biopsy
What is the inheritance pattern of prion proteins?
All autosomal dominant
What are the symptoms of Gertsmann-Strausser-Scheinher syndrome?
Progressive ataxia
