All types of CJD are serious, but very rare. Worldwide, about one to two cases of CJD are diagnosed per million people each year, most often in older adults. Creutzfeldt-Jakob disease is marked by rapid mental deterioration, usually within a few months.
Early signs and symptoms typically include:. As the disease progresses, mental symptoms worsen. Most people eventually fall into a coma. Heart failure, lung respiratory failure, pneumonia or other infections are generally the cause of death, which usually occurs within a year.
In people with the rarer vCJD , psychiatric symptoms may be more apparent in the beginning. In many cases, dementia — the loss of the ability to think, reason and remember — develops later in the illness. Prions are proteins that occur naturally in the brains of animals and people. Normally, the proteins are harmless, but when they're misshapen, they can cause devastating illnesses such as BSE disease in cattle and Creutzfeldt-Jakob disease in humans.
Creutzfeldt-Jakob disease and its variants belong to a broad group of human and animal diseases known as transmissible spongiform encephalopathies TSEs. The name derives from the spongy holes, visible under a microscope, that develop in affected brain tissue. The cause of Creutzfeldt-Jakob disease and other TSEs appears to be abnormal versions of a kind of protein called a prion.
Normally these proteins are produced in our bodies and are harmless. But when they're misshapen, they become infectious and can harm normal biological processes. The risk of CJD is low. The disease can't be spread through coughing or sneezing, touching, or sexual contact. CJD can develop in three ways:. By contamination. A small number of people have developed CJD after being exposed to infected human tissue during a medical procedure, such as a cornea or skin transplant.
Also, because standard cleaning methods don't destroy abnormal prions, a few people have developed CJD after undergoing brain surgery with contaminated instruments. A small number of people have also developed the disease from eating contaminated beef.
Variant CJD is linked primarily to eating beef infected with mad cow disease bovine spongiform encephalopathy, or BSE. In an autosomal dominant disorder, the mutated gene is a dominant gene located on one of the nonsex chromosomes autosomes. You need only one mutated gene to be affected by this type of disorder. Most cases of Creutzfeldt-Jakob disease occur for unknown reasons, and no risk factors can be identified.
However, a few factors seem to be associated with different kinds of CJD :. Exposure to contaminated tissue. People who've received infected manufactured human growth hormone, or who've had transplants of the infected tissues that cover the brain dura mater , may be at risk of iatrogenic CJD. What causes prion disease? Who is at risk for prion diseases?
Symptoms of prion diseases include: Rapidly developing dementia Difficulty walking and changes in gait Hallucinations Muscle stiffness Confusion Fatigue Difficulty speaking.
How are prion diseases diagnosed? The tests include: MRI magnetic resonance imaging scans of the brain Samples of fluid from the spinal cord spinal tap, also called lumbar puncture Electroencephalogram, which analyzes brain waves; this painless test requires placing electrodes on the scalp Blood tests Neurologic and visual exams to check for nerve damage and vision loss How are prion diseases treated?
Can prion diseases be prevented? Living with prion diseases As prion diseases progress, people with these diseases generally need help taking care of themselves. Key points about prion diseases Prion diseases are very rare. Symptoms can progress rapidly requiring help with daily needs. Prion diseases are always fatal. Next steps Tips to help you get the most from a visit to your healthcare provider: Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered. Bring someone with you to help you ask questions and remember what your provider tells you. At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you. Know why a new medicine or treatment is prescribed, and how it will help you.
Also know what the side effects are. Ask if your condition can be treated in other ways. Know why a test or procedure is recommended and what the results could mean. Know what to expect if you do not take the medicine or have the test or procedure. The prion that causes variant CJD can also be transmitted by blood transfusion , although this has only happened 5 times in the UK.
Familial CJD is a very rare genetic condition where one of the genes a person inherits from their parent the prion protein gene carries a mutation that causes prions to form in their brain during adulthood, triggering the symptoms of CJD. The symptoms of familial CJD usually first develop in people when they're in their early 50s. Iatrogenic CJD is where the infection is accidentally spread from someone with CJD through medical or surgical treatment.
For example, a common cause of iatrogenic CJD in the past was growth hormone treatment using human pituitary growth hormones extracted from deceased individuals, some of whom were infected with CJD.
Synthetic versions of human growth hormone have been used since , so this is no longer a risk. Iatrogenic CJD can also occur if instruments used during brain surgery on a person with CJD aren't properly cleaned between each surgical procedure and are reused on another person. But increased awareness of these risks means iatrogenic CJD is now very rare. In , there was 1 death from iatrogenic CJD in the UK caused by receiving human growth hormone before There's currently no cure for CJD, so treatment aims to relieve symptoms and make the affected person feel as comfortable as possible.
This can include using medicine such as antidepressants to help with anxiety and depression , and painkillers to relieve pain. Read more about treating Creutzfeldt-Jakob disease.
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