Variant Creutzfeldt–Jakob disease
Variant Creutzfeldt–Jakob disease (vCJD), commonly referred to as "mad cow disease" or "human mad cow disease" to distinguish it from its BSE counterpart, is a fatal type of brain disease within the transmissible spongiform encephalopathy family. Initial symptoms include psychiatric problems, behavioral changes, and painful sensations. In the later stages of the illness, patients may exhibit poor coordination, dementia and involuntary movements. The length of time between exposure and the development of symptoms is unclear, but is believed to be years to decades. Average life expectancy following the onset of symptoms is 13 months.
| Variant Creutzfeldt–Jakob disease | |
|---|---|
| Other names | New variant Creutzfeldt–Jakob disease (nvCJD), human mad cow disease |
| Biopsy of the tonsil in variant CJD. Prion protein immunostaining. | |
| Specialty | Infectious disease, Neurology |
| Symptoms | Initial: Psychiatric problems, behavioral changes, painful sensations Later: Poor coordination, dementia, hallucinations, involuntary movements |
| Usual onset | Years after initial exposure |
| Duration | ~13-month life expectancy after onset of symptoms |
| Causes | Prions |
| Risk factors | Eating beef from cows with bovine spongiform encephalopathy |
| Diagnostic method | Suspected based on symptoms, confirmed by brain biopsy |
| Differential diagnosis | Multiple sclerosis, standard Creutzfeldt-Jakob disease |
| Prevention | Not eating contaminated beef |
| Treatment | Supportive care |
| Prognosis | Always fatal |
| Frequency | Fewer than 250 reported cases as of 2012 |
It is caused by prions, which are misfolded proteins. Spread is believed to be primarily due to eating bovine spongiform encephalopathy (BSE) infected beef. Infection is also believed to require a specific genetic susceptibility. Spread may potentially also occur via blood products or contaminated surgical equipment. Diagnosis is by brain biopsy but can be suspected based on certain other criteria. It is different from typical Creutzfeldt–Jakob disease, though both are due to prions.
Treatment for vCJD involves supportive care. As of 1990, 178 cases of vCJD have been recorded in the United Kingdom, due to a 1990s outbreak, and 50 cases in the rest of the world. The disease has become less common since 2000. The typical age of onset is less than 30 years old. It was first identified in 1996 by the National CJD Surveillance Unit in Edinburgh, Scotland.