Creutzfeldt-Jakob Disease

Creutzfeldt-Jakob disease (CJD) is a rare, degenerative and fatal brain disorder caused by an infectious agent known as a "prion." In the United States, there are about 200 cases of CJD a year, or less than one case per 1 million population. Typically, the disease occurs at about age 60 and 90 percent of patients diagnosed with CJD die within a year.

In the early stages, symptoms may include include failing memory, behavioral changes, lack of coordination and vision problems. As the illness progresses, mental deterioration becomes more severe and involuntary movements, blindness, weakness in the arms and legs and then coma may occur.

CJD may occur in three ways:

• Sporadically without apparent cause and no known risk factors. This is the common form of Creutzfeldt-Jakob disease and accounts for about 85 percent of cases.

• Hereditary CJD in which there is a family history or a genetic mutation associated with the disease. About 5 percent to 10 percent of cases in the United States are hereditary.

• Transmitted through infection by exposure to brain or nervous system tissue, usually through medical procedures. There is no evidence that Creutzfeldt-Jakob disease is contagious or that it can be spread through casual contact with a patient. Since 1920, less than 1 percent of the reported cases were acquired through infection.

Creutzfeldt-Jakob disease is part of a family of diseases known as transmissible spongiform encephalopathies (TSE). Spongiform refers to the appearance of the infected brain, which becomes filled with holes until it resembles a sponge under a microscope. CJD is the most common of these diseases. Other forms occur in animals such as bovine spongiform encephalopathy (BSE), which develops in cows and often is referred to as "mad cow" disease. Similar diseases occur in cats, elk, deer, goats, sheep and exotic zoo animals.

You may need a referral from your primary care doctor. Please check with your medical benefits or health insurance representative.

See books recommended by the UCSF Memory and Aging Center.

Reviewed by health care specialists at UCSF Medical Center.
Last updated February 8, 2008