Prion Disease Flashcards
what are prions
misfolded forms of the normal protein, can transform other proteins into prion proteins - domino effect
what pathological changes do prion proteins cause in the brain
spongiform changes
also neuronal loss, astrocytosis and amyloid plaque formation
are prion diseases progressive
rapidly
age of onset of sCJD
60s
duration of sCJD illness
4 months
clinical features of sCJD
Rapid onset dementia + neurological signs + myoclonus
Urinary incontinence and gait abnormalities
how is sCJD caused
production of prion proteins
age of onset of vCJD
20s
how does vCJD present
Painful sensory disturbance + neuropsychiatric decline
how long does vCJD last
14 months
aetiology of vCJD
Found outside CNS in gut, liver, salivary glands, kidney, lung and bone marrow
Exposure to BSE (mad cow) via contaminated meat (beef) or blood
is vCJD common
no <1% frequency
imaging of vCJD
hockey stick sign on MRI - thalamuc nuclei
how does iCJD present
Cerebellar/visual onset. Multifocal neurological decline.
how long does iCJD last for
<2 years
aetiology of iCJD
transmission of prion proteins through medical procedures
eg pituitary hormone replacement, surgical instruments, dura mater grafts, corneal transplants
which part of the brain can be grafted and can transmit iCJD
dura mater
which type of CJD may genetic CJD mimic
sporadic
age of onset of gCJD
any
what are teh 2 subtypes of gCJD
Gerstmann-Straussler-Scheinker disease and fatal familial insomnia
how does Gerstmann-Straussler-Scheinker disease present
progressive ataxia - progressive degeneration of the cerebellum and differnet degreres of dementia
which gene is mutated in gCJD
PRNP - there are more than 30 mutations and each produces its own phenotype
what is the best inital test
EEG
what other tests are performed
MRI and LP
what is seen on LP
elevated 14-3-3 protein
management
currently there is none, focus on supportive care, genetic counselling in familial forms
main aim is to prevent transmission!!!
