Creutzfeld-Jakob Disease Flashcards
The main features of CJD
Rapidly progressive subcortical dementia (over the course of ~months)
Begins with muscle coordination problems, personality change, impairment of memory and judgement
Late in the disease course, UMN sign, ataxia, vision loss, and myoclonus are often present
Eventually, they enter a coma
Four categories of CJD
- Sporadic CJD
- Hereditary CJD
- Acquired CJD
- Variant CJD
Sporadic CJD
- Appearance of the disease in an individual with no known risk factors
- ~85% of cases of CJD
Hereditary CJD
- CJD in an individual with a positive family history for CJD and/or a positive screen for a mutation associated with CJD
- ~5-10% of cases in the US are hereditary
Acquired CJD
- Form of CJD transmitted by exposure to brain or CNS tissue, usually through medical procedures
- CJD is NOT contagious through casual contact with a CJD patient
- Accounts for <1% of cases of CJD
Variant CJD
- Transmitted by ingestion of meat products from cattle infected with bovine spongiform encephalopathy
- Presents at a younger age than sporadic CJD and has a more protracted course
- Psychiatric disturbance is the initial presentation, as opposed to rapidly progressive subcortical dementia in sporadic CJD
The typical age of onset of sporadic or hereditary CJD is. . .
. . . around age 60
Transmissible spongiform encephalopathies
- Family of human and animal prion diseases associated with “spongiform” appearance of infected brains (tissue filled with holes until they resemble sponges under a microscope)
- CJD is the most common transmissible spongiform encephalopathy
- Others include:
- Kuru (transmissible, but only through cannibalism)
- Fatal familial insomnia (heritable)
- Gerstmann-Straussler-Scheinker disease (heritable)
Cortical ribboning
Imaging sign associated with sporadic CJD
Enhancement of a stretch of cortical gray matter
CJD on MRI
Typical CJD imaging showing enhancement in the basal ganglia, caudate, and putamen
The diagnosis of CJD is not infrequently made on . . .
. . . autopsy
Given its highly specific pathology findings. The clinical syndrome is sometimes mistaken for Huntington’s, Alzheimer’s, or a subcortical dementia and then corrected retroactively.
To avoid transmission of CJD, you want to avoid. . .
. . . contact with brain tissue and CSF
But other household members of a patient with CJD are not at risk for infection
Diagnosis of CJD
- No single diagnostic test exists
- Clinically suspected based on rapid course, presence of myoclonus and gait disorder
- Rather, the focus of the diagnostic workup in CJD is to rule out treatable forms of dementia/AMS (encephalitis, meningitis, toxic-metabolic, autoimmune, paraneoplastic, demyelinating disease, vasculitis, malignancy)
- Specific tests:
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EEG
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Often shows periodic sharp wave complexes (sens 66%, spec 74% for CJD)
- Note: Look similar to K complexes to me, but out-of-context in an awake patient
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Often shows periodic sharp wave complexes (sens 66%, spec 74% for CJD)
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CT brain
- Can rule out stroke or intracranial tumor
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MRI brain
- Can reveal characteristic patterns of brain degeneration to aid in diagnosis
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EEG
Hashimoto encephalopathy
Condition caused by autoantibodies found in patients with Hashimoto thyroiditis (though it can occur in patients with normal thyroid function).
Can cause cognitive and vigilance impairment, ataxia, myoclonus, and epileptic seizures.
May be mistaken for early CJD due to the timeframe and presence of myoclonus.
Brain biopsy in CJD
Discouraged unless it is needed to rule out a treatable alternative diagnosis to CJD
Additionally, poses a small but real risk of transmission of CJD to the surgeon and surgical team