prion diseases

Prion diseases 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
• kuru
• variably protease-sensitive prionopathy

Pathology

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.

Radiographic features

MRI

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.

Siehe auch:

• Creutzfeldt-Jakob-Krankheit
• Transmissible spongiforme Enzephalopathie
• Bovine spongiforme Enzephalopathie

und weiter:

• neuroradiologisches Curriculum
• prions