CreutzfeldtJakob

Creutzfeldt-Jakob disease, often abbreviated as CJD, is a rare, rapidly progressive neurodegenerative disorder caused by prions, misfolded forms of the normal prion protein that induce brain tissue damage. It is classified as a prion disease and occurs in sporadic, familial, iatrogenic, and variant forms.

Most cases are sporadic, with no known source. Familial CJD results from inherited mutations in the PRNP gene. Iatrogenic cases have occurred after exposure to contaminated human-derived materials, such as dura mater grafts or growth hormone. Variant CJD (vCJD) is linked to consumption of beef contaminated with bovine spongiform encephalopathy (BSE) prions; it tends to affect younger individuals and has distinct clinical and pathological features.

Clinically, CJD presents with a rapidly progressive decline in cognition, behavioral changes, myoclonus, visual disturbances, and ataxia, followed by a marked reduction in mobility and ultimately akinetic mutism. The disease typically progresses over months, leading to severe disability and death.

Diagnosis relies on a combination of clinical suspicion and supportive investigations. MRI with diffusion-weighted imaging often shows characteristic signal changes in the cortex and deep gray matter. EEG may reveal periodic sharp wave complexes. CSF testing can detect prion-related biomarkers such as 14-3-3 protein and elevated tau; the RT-QuIC assay is highly specific. Definitive diagnosis is by neuropathological examination showing spongiform changes and PrPSc deposition; genetic testing of PRNP helps identify familial forms.

There is no cure for CJD; management is supportive and focused on symptom relief and infection control. The prognosis is poor, with most patients dying within a year of onset. The incidence is about 1 per million people per year worldwide.