Citation, DOI & article data
Prion diseases, also known as transmissible spongiform encephalopathies, are caused by the accumulation of dysmorphic proteins named prions, and are characterized by progressive neurological decline and eventual death. In humans, these diseases include:
- Creutzfeldt-Jakob disease (sporadic, variant, familial and iatrogenic)
- fatal familial insomnia
- Gerstmann-Straussler-Scheinker disease
- variably protease-sensitive prionopathy
They are all mediated by prions: abnormally folded self-catalyzing endogenous proteins which accumulate within the nervous system. Diagnosis has been problematic as imaging findings are variable and CSF protein analysis (14-3-3 protein) insensitive.
Brain biopsy is accurate but is fraught with difficulties as equipment needs to be discarded (prions have been found to survive standard autoclaving procedures) and staff precautions are difficult to implement.
DWI changes are the earliest imaging manifestation prior to FLAIR and cerebral volume changes. Typically, cortical and deep grey matter (caudate, thalamus and putamen) demonstrates increased signal, not confined to vascular territories.
Treatment and prognosis
There is no curative treatment available for any prion disease.
History and etymology
The term spongiform is derived from the histological appearance of cerebral tissue characterized by neuronal degeneration with peculiar vacuolation reminiscent of a sponge.
Although Creutzfeldt-Jakob disease had been clinically described in 1921, it was not until 1959 when a similarity between kuru (only described in 1957) and scrapies (a similar disease affecting sheep) was recognized by veterinary pathologist W J Hadlow, that prion disease was recognized as a group of related pathologies 2.
- 1. Macfarlane RG, Wroe SJ, Collinge J et-al. Neuroimaging findings in human prion disease. J. Neurol. Neurosurg. Psychiatr. 2006;78 (7): 664-70. doi:10.1136/jnnp.2006.094821 - Free text at pubmed - Pubmed citation
- 2. Asher D & Gregori L. Human Transmissible Spongiform Encephalopathies: Historic View. Human Prion Diseases. 2018;:1-17. doi:10.1016/b978-0-444-63945-5.00001-5