34c - Prions Flashcards
What are the progressive neurological disorders caused by infectious agents?
subacute sclerosing panecephalitis -measles
post-rubella panencephalitis
AIDS dementia complex
Progressive multifocal leukoencephalopathy - polyoma (JC)
Pathology of transmissible spongiform encephalopathies?
long incubate, rapid progression to fatal dementia.
Multifocal spongiform changes, astrogliosis, neuronal loss, amyloid plaques in some forms, minimal inflammation.
What chromosome is the prion protein exon encoded on?
Chromosome 20 in a single exon
What is PrPc?
the normal cell form of a prion protein
What is PrPsc?
pathogenic form of prion protein
WHat is PrPres?
pathogenic form of prion protein
What is scrapie?
a subacute, progressive ataxia of sheep. first found at 1 year of age in lymphatic tissues and itestines. By age 2 brain, followed by spongiform and disease.
What is Kuru?
first documented human TSE from Papua New Guinea and ritual cannibalism
What is CJD?
most common human TSE. clinical features of dementia, myoclonus, ataxia, and mutism near death. There are three forms.
What are the three forms of CJD?
sporadic (85%)
iatrogenic
familial
What is most common form of CJD?
sporadic (85%)
What is iatrogenic CJD?
transmitted from dural grafts, corneal grafts and hGH. Incubation of 1-2 years.
What is familial CJD?
15% of CJD, autosomal dominant pattern of transmission. Average age of onset is 45-50 years old. and Mean survival time from onset is 2 years.
How is CJD diagnosed?
Clincical course (rapidly progressive dimensia and myoclonus) Confirm by histology - cerebral spongiform changes, genreal lack of amyloid plaques.
Which type of CJD has specific EEG periodic complexes?
sporadic form.