Prion Diseases

Creutzfeldt-Jakob Disease (CJD) is a rare illness and is one of a group of diseases called prion diseases, which affect humans and animals.  Prion diseases exist in different forms, all of which are progressive, currently untreatable and ultimately fatal. 
They are caused by the presence of an abnormal protein in the brain tissue, called prion protein (PrPSc), and is believed to result from a change in the shape, of a normal cellular protein (PrPC ) which is present in the brain. As the amount of abnormal prion protein grows, it becomes hard to break down, causing brain degeneration and neurologic disease.
Prion Diseases are extremely rare reportedly affecting one to two people per million of the population each year worldwide; equating to ~ 4-10 cases annually in Ireland.

Prion diseases exist in different forms

Sporadic CJD

Sporadic is the most prevalent of the Human Prion Diseases, accounting for ~85% of all those identified. The cause of Sporadic human Prion Disease is not known, but it is thought to be due to spontaneous misfolding of the normal prion protein (PrPc).

Iatrogenic CJD 

Transmitted by infection due to exposure to the infectious prion (PrPSc) from transplant of contaminated tissues, or use of contaminated instruments during specific surgical procedures. Iatrogenic internationally account for less than 0.1%.

Variant CJD

Since the first report in 1996, a total of 229 vCJD cases have been reported worldwide: 177 in the United Kingdom; 27 in France; and 25 distributed in 10 other countries, including Ireland (4).

Genetic CJD

Genetic forms of human Prion Diseases (also called familial or inherited) are caused by mutations in the prion protein gene PRNP. They account for approximately 15% of all human Prion Diseases.

Diagnostic Criteria 

Patients are classified according to their ability to fulfil internationally accepted Diagnostic Criteria and when other appropriate diseases have been ruled out.


Please visit the presentation below for more information about Prion Diseases


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