​Infectious Diseases and Microbiology - Creutzfeldt-Jakob Disease (CJD) (Prion)

​Infectious Diseases and Microbiology - Creutzfeldt-Jakob Disease (CJD) (Prion) 
 Prion diseases are unusual agents that cause CJD, a rare disease with just one case per million individuals. The majority of cases (85%) of CJD are sporadic; 10%–15% are familial. Iatrogenic transmission of CJD has been identified following the use of infected medical devices (brain electrodes) that have not been fully sterilized between patients, transplantation of contaminated corneal grafts, dura mater grafts, injection of human pituitary derived growth hormone, and transplantation of contaminated corneal grafts. New variant CJD is contracted by eating meat tainted with bovine spongiform encephalopathy, and it can spread between people through blood transfusions.

CJD is a neurological condition that progresses over time and often manifests between the ages of 50 and 70. Clinically, CJD is marked by ataxia, myoclonus (involuntary movements), and dementia. Within six months to a year, the illness worsens to the point of severe dementia and death.
A conformationally altered protease-resistant variant of a normal cellular protein called prion protein, or PrPc, is thought to accumulate in neurons and cause prion disorders. In order to cause a conformational change in PrPc and transform it into the aberrant PrPsc form, the abnormal PrPs c attaches to normal PrPc and functions as a template. Until aberrant PrPsc accumulates to levels linked to neuronal dysfunction and neuronal death, the process carries on in a cascading manner. The pathognomonic feature associated with the production of amyloid-like fibrils and plaques in the brain is the accumulation of PrPsc. Pathology also shows extensive vacuolation, neuronal loss, and gliosis. Prions are nonantigenic host proteins, which allows them to evade immune surveillance.

 When brain sections are examined histopathologically after death, typical spongiform alterations that are identified by a "spongy" appearance (holes in the tissue) are seen.

 To avoid prion illnesses, there is no specific medication and no immunologic strategy.

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