Creutzfeldt-Jakob Disease

Summary

• Creutzfeldt-Jakob disease (CJD) is a rare, degenerative, invariably fatal brain disorder.  
• Variant CJD can be regarded as the human version of "mad cow disease", known as Bovine Spongiform Encephalitis (BSE) in cattle.
• Scientists believe people contract variant CJD by eating beef infected with BSE, which emerged in 1986 in Britain and developed into an epidemic when farmers added recycled meat and bone meal from infected cows into cattle feed.
• There are three major categories of CJD: sporadic CJD, hereditary CJD and acquired or variant CJD.  
• There is currently no single diagnostic test for CJD.  
• There is no current cure for CJD, but treatment is aimed at alleviating symptoms and making the patient as comfortable as possible.  
• About 90 percent of patients die within a year.
• Typically, onset of symptoms occurs at about age 60.
• It may be thought of as an infectious disease caused by a protein, rather than a virus or bacterium.
• While CJD can be transmitted to other people, the risk of this happening is extremely small.

The human version of "mad cow disease"

Variant CJD can be regarded as the human version of "mad cow disease", known as Bovine Spongiform Encephalitis (BSE) in cattle. Scientists believe people contract variant CJD by eating beef infected with BSE. Variant CJD emerged in Britain in 1986 and developed into an epidemic when farmers added recycled meat and bone meal from infected cows into cattle feed.

The 100th case was confirmed in May 2001.

According to scientists, some cattle carcasses culled as part of the foot-and-mouth disease eradication programme may have to be dug up and burned because of the threat of spreading the cattle disease.

In Britain the sheer scale of animals slaughtered and buried whole or burned on makeshift pyres has raised fears that the disease could enter the water supply if burial sites were not properly lined.

Diagnosis

There is currently no single diagnostic test for CJD. The first concern is to rule out treatable forms of dementia such as encephalitis or chronic meningitis. The only way to confirm a diagnosis of CJD is by brain biopsy or autopsy.

In a brain biopsy, a neurosurgeon removes a small piece of tissue from the patient's brain so that it can be examined by a pathologist. Because a correct diagnosis of CJD does not help the patient, a brain biopsy is discouraged unless it is needed to rule out a treatable disorder.

Prognosis

About 90 percent of patients die within a year. In the early stages of the disease, patients may have failing memory, behavioral changes, lack of coordination and visual disturbances.

As the illness progresses, mental deterioration becomes pronounced and involuntary movements, blindness, weakness of extremities and coma may occur.

Treatment

There is no treatment that can cure or control CJD. Current treatment is aimed at alleviating symptoms and making the patient as comfortable as possible.

Opiate drugs can help relieve pain and the drugs clonazepam and sodium valproate may help relieve involuntary muscle jerks.

Reviewed by Dr Andrew Rose-Innes, MD, Department of Neurology, Yale University School of Medicine, New Haven, 2007