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Variably Protease-Sensitive Prionopathy (VPSPr)


Brian Appleby

, MD, Case Western Reserve University

Last review/revision Nov 2022
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Variably protease-sensitive prionopathy (VPSPr) is a rare sporadic prion disease (identified in 2008).

Variably protease-sensitive prionopathy occurs in 1 to 2/100 million people.

Clinical manifestations differ from those of Creutzfeldt-Jakob disease Creutzfeldt-Jakob Disease (CJD) Creutzfeldt-Jakob disease (CJD) is the most common human prion disease. It occurs worldwide and has several forms and subtypes. CJD symptoms include dementia, myoclonus, and other central nervous... read more , and the PrPSc is less resistant to digestion by proteases; some variants are more sensitive to proteases than others, hence the name: variably protease-sensitive.

Patients present with psychiatric symptoms, speech deficits (aphasia and/or dysarthria), and cognitive impairment. Ataxia and parkinsonism can develop. Average age at onset is 70 years, and duration of survival is 24 months. About 40% of patients have a family history of dementia.

Diagnosis of variably protease-sensitive prionopathy is difficult. MRI, EEG, and tests for 14-3-3 protein and tau are usually not helpful, and no mutations have been observed in the coding region of the PRNP gene.

There is only supportive treatment for VPSPr.

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