Makindo Medical Notes.com

Related Subjects: |Dementias |Gerstmann-Straussler-Scheinker Syndrome (GSS) |Fatal Familial Insomnia (FFI) |Creutzfeldt Jakob disease (CJD) |Variant Creutzfeldt Jakob disease (vCJD) |Kuru

About

• Classical form preceded BSE and is unrelated to it
• Affects older patients with a more aggressive course

Types

• Most are sporadic
• Familial causes 5-15% with autosomal dominant inheritance
• Iatrogenic from Pituitary extract for GH/Corneal transplant/Dura mater implantation

Criteria

• Definite
  • Diagnosed by standard neuropathological techniques; and/or immunocytochemically; and/or Western blot confirmed protease-resistant PrP; and /or presence of scrapie-associated fibrils.
• Probable
  • Neuropsychiatric disorder plus positive RT-QuIC in cerebrospinal fluid (CSF) or other tissues
  • OR
  • Rapidly progressive dementia; and at least two out of the following four clinical features
    • Myoclonus
    • Visual or cerebellar signs
    • Pyramidal/extrapyramidal signs
    • Akinetic mutism
    • AND a positive on one of these
      • Typical EEG (periodic sharp wave complexes) during an illness of any duration
      • CSF positive 14-3-3 with a disease duration of less than 2 years
      • MRI: High signal in caudate/putamen or at least two cortical regions (temporal, parietal, occipital) either on diffusion-weighted imaging (DWI) or fluid attenuated inversion recovery (FLAIR)
• Possible: Progressive dementia; and at least two out of the following four clinical features
  • Myoclonus
  • Visual or cerebellar signs
  • Pyramidal/extrapyramidal signs
  • Akinetic mutism

Clinical and Pathologic Characteristics Distinguishing Classic CJD from Variant CJD

Clinical

• Rapidly presenting dementia with myoclonus
• Behavioural changes and the diagnosis can be protean
• It is quite possible many cases especially in older patients are missed
• The new variant one suspected to be BSE related affects younger people and dementia develops late

Investigations

• Post mortem: Brain becomes Spongiform with atrophy in the cerebral cortex, basal ganglia thalamus and cerebellum and Amyloid plaques found
• EEG:periodic triphasic sharp-wave complexes
• CSF: Protein 14-3-3 (also seen in MS and acute stroke)
• MRI of the brain - often shows high signal intensity in the caudate nucleus and putamen bilaterally on T2-weighted images
• Brain biopsy gold standard staining for PrP^Sc Prion protein(scrapie)

Management

• None - only supportive
• Inform CJD surveillance unit if you have a suspected case
• Genetic counselling for familial types