Creutzfeldt-Jakob disease (CJD)
Creutzfeldt-Jakob disease is a prion disorder causing relentlessly progressive dementia with myoclonus, ataxia, and visual disturbance, typically fatal within about a year. Diagnosis rests on characteristic diffusion-weighted MRI changes and the real-time quaking-induced conversion assay of cerebrospinal fluid; no disease-modifying therapy exists.
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What this article covers
- Overview
Definition: Creutzfeldt-Jakob disease (CJD) is a prion-related neurodegenerative disorder causing relentlessly progressive, rapidly fatal dementia, the most common human prion disease.
- Epidemiology
Rarity: CJD is rare relative to the common neurodegenerative dementias (Alzheimer disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia), but its rapid, uniformly fatal…
- Risk factors
Spontaneous somatic mutation: the mechanism underlying most (sporadic) cases; no identifiable exogenous risk factor is present in this group.
- Pathophysiology
Protein misfolding and templated conversion: the pathogenic prion protein adopts an abnormal conformation that catalyzes the conversion of normal host prion protein into the same misfolded…
- Clinical features
Rapidly progressive dementia: cognitive decline that progresses over weeks to a few months, far faster than the typical multi-year course of Alzheimer disease or other common dementias.
- Differential diagnosis
Paraneoplastic encephalopathy: subacute cognitive decline associated with an underlying malignancy and specific autoantibodies; tumor screening and antibody panels distinguish it from prion disease, and the clinical tempo can overlap.
- Diagnosis
Diagnostic basis: CJD is a clinicoradiologic diagnosis established by the combination of a compatible rapidly progressive dementia syndrome with characteristic MRI findings, supported by CSF prion…
- Management
First step once the diagnosis is established and treatable mimics have been excluded: shift explicitly to supportive and symptomatic management, since no known intervention alters the course of the…
- Complications
Progressive functional decline: rapid loss of independence in activities of daily living as cognitive, motor, and visual function deteriorate over weeks to months.
- Prognosis
Uniformly fatal, short course: time from disease onset to death is approximately 12 months in as many as 80% of patients with CJD, among the most rapid courses of any neurodegenerative disease.
- Prevention
No primary prevention for sporadic disease: because sporadic CJD arises from a spontaneous somatic mutation, there is no modifiable risk factor or screening strategy to prevent it.
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