Overview, Causes, & Risk Factors
The classic form of Creutzfeldt-Jakob disease, or CJD, is an infectious disease that causes progressive brain damage and death. New variant Creutzfeldt-Jakob disease, or nvCJD, is a slightly different form of CJD. The new variant of CJD is most likely the human form of mad cow disease.
What is going on in the body?
Both classic and new variant CJD are prion diseases. Prions are a modified form of a protein found on normal cell surfaces. Both diseases cause a buildup of prions in the brain. The increase in prions causes brain injury and degeneration. The same type of prion may cause both mad cow disease and nvCJD.
The classic form of CJD may cause symptoms 15 months to 30 years after exposure. New variant CJD may take 5 to 10 years to develop after the person has been exposed to the prion.
What are the causes and risks of the disease?
There are three main causes for classic CJD. Inherited CJD runs in families and is caused by a mutation in the gene coding for the normal prion protein. Sporadic CJD has no known genetic or infectious cause.
Creutzfeldt-Jakob disease through infection is transmitted by prions. The individual is infected through direct or indirect contact with body tissues of an infected person. Following are some examples of this transmission:
There is a strong link between mad cow disease and the new variant of CJD. Most scientists believe that this new variant CJD is the human form of mad cow disease. It is believed that the abnormal prion is transmitted from infected cattle to humans when the person eats meat or beef products. Milk and dairy products from infected cattle don’t appear to transmit the disease.
At the present time, infected cattle are found mostly in Europe, particularly the United Kingdom. Even in the UK, the risk of getting nvCJD from eating infected beef is only about 1 case per 10 billion servings.
The classic form of Creutzfeldt-Jakob disease is most common in people from 50 to 75 years of age. New variant CJD is seen most often in teens and young adults.
Symptoms & Signs
What are the signs and symptoms of the disease?
The classic form of CJD causes rapid, progressive dementia. The individual becomes increasingly more confused and disoriented. The person may have visual and speech impairments, muscle spasms, and personality changes.
New variant CJD has different symptoms from the classic form. Early in the course of the disease, the person may have psychiatric disorders and altered sensations. Later, the person can develop ataxia, or difficulty walking. Muscle spasms and dementia show up late in the illness. There may be visual impairments, paralysis, and sleep disorders.
Diagnosis & Tests
How is the disease diagnosed?
Diagnosis of CJD begins with a medical history and physical exam. An EEG, or recording of the brain waves, may show abnormalities. A final diagnosis can be made with a biopsy of the brain. This involves taking a small piece of brain tissue with a special needle. The piece of tissue can then be examined with a microscope.
Prevention & Expectations
What can be done to prevent the disease?
Travelers to areas with a high risk for mad cow disease can limit their risk for new variant CJD by avoiding beef and beef products. If the person chooses to eat meat, he or she should select solid pieces of muscle meat, such as a steak or roast. Sausage and hamburger should be avoided. Public health measures to include testing mad cow disease and eliminating infected cattle.
What are the long-term effects of the disease?
CJD causes progressive brain deterioration and death.
What are the risks to others?
CJD does not seem to spread from person to person. However, it may be spread through direct or indirect contact with infected body tissue.
Treatment & Monitoring
What are the treatments for the disease?
There is no treatment for CJD. Medications may used to treat psychiatric problems or relieve symptoms.
What are the side effects of the treatments?
Medications may cause allergic reactions and stomach upset.
What happens after treatment for the disease?
CJD causes progressive brain damage and death. The classic form usually causes death within 6 to 12 months of the initial symptoms. Someone who has new variant CJD usually dies within 2 years of the initial symptoms.
How is the disease monitored?
The individual may have periodic visits with the healthcare provider to monitor the disease. Any new or worsening symptoms should be reported to the provider.
Article type: xmedgeneral