Movement Disorders in Prionopathies: A Systematic Review

Area of Science:

• Neurology
• Neuroscience
• Prion Disease Research

Background:

• Movement disorders are characteristic but poorly documented in prion diseases.
• Understanding their prevalence and onset is crucial for diagnosis and management.

Purpose of the Study:

• To systematically review and describe the prevalence and onset of movement disorders in various prionopathies.
• To investigate associations between movement disorder phenomenology and prion disease subtypes or PRNP genotype.

Main Methods:

• Systematic review of pathologically and genetically confirmed prionopathy case reports and series.
• Documentation of symptom and movement disorder onset timing.
• Statistical comparison of continuous and categorical variables between disease groups.

Main Results:

• Movement disorders are common at symptom onset in most prionopathies, with gait ataxia exceeding 50%.
• Gerstmann-Sträussler-Scheinker disease showed lower limb ataxia and myoclonus rates compared to others.
• Chorea was more prevalent in variant Creutzfeldt-Jakob disease; myoclonus appeared late in sporadic Creutzfeldt-Jakob disease.

Conclusions:

• Movement disorder presentation differs across prionopathies, influenced by disease type and PRNP genotype.
• The late onset of myoclonus in sporadic CJD may hinder early diagnosis.