Creutzfeldt-Jakob Disease (CJD - Prion Disease)

Spontaneous misfolding of prion protein initiates sporadic CJD.

Ingestion of prion-contaminated food products triggers variant CJD.

Exposure to contaminated neurosurgical instruments or grafts causes iatrogenic CJD.

Inheritance of pathogenic PRNP mutations initiates familial CJD.

Sporadic CJD has a rapid onset with symptoms developing within weeks to months after prion formation.

Variant CJD has a prolonged incubation period of several years to decades after exposure.

Iatrogenic CJD latency varies widely from months to years depending on exposure route.

Familial CJD symptoms typically appear in mid-adulthood but can vary widely.

Rapidly progressive dementia is often misattributed to other neurodegenerative diseases or psychiatric disorders.

Early nonspecific symptoms such as fatigue and mood changes delay suspicion of CJD.

Lack of definitive antemortem diagnostic tests leads to delayed diagnosis.

Low clinical awareness due to rarity contributes to misdiagnosis.

Overlap with other causes of encephalopathy or dementia complicates early recognition.

Rapidly progressive dementia developing over weeks to months is the cardinal clinical feature.

Myoclonus often stimulus-sensitive and generalized is a classic symptom.

Visual disturbances including cortical blindness or diplopia occur in some variants.

Ataxia and gait disturbances appear early or as the disease progresses.

Behavioral changes such as anxiety, depression, and psychosis may be present.

Rapidly progressive dementia with cognitive decline over weeks to months is typical.

Myoclonus, visual disturbances, and cerebellar ataxia develop early in the course.

Behavioral changes and psychiatric symptoms such as anxiety or depression often precede cognitive decline.

Progressive akinetic mutism and coma occur in late stages.

Symptoms worsen relentlessly leading to death usually within 1 year of onset.

History of neurosurgical procedures or dura mater grafts increases iatrogenic CJD risk.

Prior corneal transplantation or use of human-derived growth hormone is relevant.

Family history of rapidly progressive dementia suggests familial CJD.

No specific past medical conditions are required for sporadic CJD.

Autosomal dominant inheritance of PRNP mutations causes familial CJD.

Affected first-degree relatives with similar rapidly progressive dementia support familial form.

Some families show variable penetrance and age of onset.

No family history is typical in sporadic and variant CJD cases.

Myoclonus, especially stimulus-sensitive, is a hallmark finding in Creutzfeldt-Jakob disease.

Ataxia with gait instability and dysmetria is commonly observed due to cerebellar involvement.

Extrapyramidal signs such as rigidity and bradykinesia may be present in later stages.

Cortical blindness or visual disturbances can be detected on exam in some cases.

Rapidly progressive dementia manifests as impaired attention, memory, and executive function.

Provide comprehensive supportive care including symptom management and prevention of complications such as infections and pressure ulcers.

Implement safety measures to prevent injury due to rapidly progressive dementia and motor dysfunction.

Offer psychological support and counseling for patients and families due to the devastating prognosis.