Prion disease: Difference between revisions

 
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==Clinical Features==
==Clinical Features==
*Progressive [[dementia]], behavioral changes, loss of cortical function over several months
*Progressive [[dementia]], behavioral changes, loss of cortical function over several months on average
*Myoclonus
*Myoclonus
*[[Extrapyramidal symptoms]] (hypokinesia)
*[[Extrapyramidal symptoms]] (hypokinesia)
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==Evaluation==
==Evaluation==
*'''Not''' an ED diagnosis, as definitive diagnosis only possible by autopsy
*'''Not''' an ED diagnosis, however MRI (if done) can raise significant suspicion and provide a presumptive diagnosis in the right clinical context
*LP with CSF studies can be diagnostic but should never be performed in the ED and must be done under special precautions
*Evaluate for reversible/treatable causes of dementia
*Evaluate for reversible/treatable causes of dementia
**CBC, B12, folate, thiamine
**CBC, B12, folate, thiamine
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**ETOH, [[Utox]], urine heavy metals
**ETOH, [[Utox]], urine heavy metals
**RPR, ESR, ANA, HIV
**RPR, ESR, ANA, HIV
**[[LP]]
*[[brain MRI|MRI]]:  
*[[brain MRI|MRI]]:  
**Areas of increased signal intensity bilaterally, mostly in caudate and putamen
**Areas of increased signal intensity bilaterally, mostly in caudate and putamen
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==Management==
==Management==
*No specific treatment
*No specific treatment, doxycycline has been used but evidence is weak
*Ongoing research
*Consider [[palliative care]] consult for symptom alleviation and support
*Consider [[palliative care]] consult for symptom alleviation and support



Latest revision as of 05:45, 20 August 2022

Background

  • Prions are misfolded proteinaceous particles
    • Replicate exponentially by causing properly folded proteins to misfold
    • Rapidly leads to neurodegeneration
  • Universally fatal
  • Transmissible forms:
    • Variant CJD acquired by consuming diseased tissues of cows (e.g. human form of mad cow disease) or other humans (kuru)
    • Iatrogenic (handling diseased corneas/brain or improperly disinfected equipment)
  • Hereditary prion disease:
    • Familial CJD: mutation in PRNP, which encodes prion protein
    • Fatal familial insomnia
    • Gerstmann-Sträussler-Scheinker syndrome
  • Sporadic CJD: accounts for ~85% of cases, cause is unknown

Clinical Features

Differential Diagnosis

Dementia

Evaluation

  • Not an ED diagnosis, however MRI (if done) can raise significant suspicion and provide a presumptive diagnosis in the right clinical context
  • LP with CSF studies can be diagnostic but should never be performed in the ED and must be done under special precautions
  • Evaluate for reversible/treatable causes of dementia
  • MRI:
    • Areas of increased signal intensity bilaterally, mostly in caudate and putamen
    • Posterior thalamic hyperintensity
  • EEG
    • Usually nonspecific but abnormal

Management

  • No specific treatment, doxycycline has been used but evidence is weak
  • Ongoing research
  • Consider palliative care consult for symptom alleviation and support

Disposition

See Also

External Links

References