Version July 2025
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What is Creutzfeldt-Jakob disease? —
Creutzfeldt-Jakob disease, or "CJD," is a rare brain disorder that causes muscle twitching and dementia. Dementia is a group of brain disorders that cause memory and thinking problems.
CJD happens most often in older adults. It is caused by abnormal proteins called "prions" that infect the brain.
There are different types of CJD:
●"Sporadic" CJD – This is the most common type. In most cases, the cause is unknown. But sometimes, it is related to an abnormal gene that can run in families. In rare cases, people have gotten CJD after they had transplant surgery and got an infected organ. CJD is not spread through sneezing, coughing, touching, or sex.
●"Variant" CJD – This is less common. It can happen after people eat beef that is infected with the disease. (This is sometimes called "mad cow disease.") But thanks to new government rules, variant CJD almost never happens anymore.
What are the symptoms of CJD? —
The 2 most common symptoms of CJD are:
●Dementia, which means trouble with concentration, memory, or thinking
●Muscle twitches or jerks, called "myoclonus"
People with CJD also usually have other symptoms, which might include:
●Behavior changes
●Mood changes, such as depression
●Trouble walking, or problems with balance
●Sleeping much more or much less than usual
These symptoms are similar to those that happen with other, more common types of dementia, such as Alzheimer disease. But in CJD, the symptoms get worse much faster than in Alzheimer disease.
Is there a test for CJD? —
Yes. Doctors usually do tests to make sure the person has CJD and not another condition. These tests can include:
●MRI of the brain – This is an imaging test that creates pictures of the brain.
●Lumbar puncture, also sometimes called a "spinal tap" – The doctor puts a thin needle into the lower back and removes a small amount of spinal fluid. This is the fluid that surrounds the brain and spinal cord. They send the spinal fluid to a lab for tests.
●"Electroencephalogram," or "EEG" – This measures electrical activity in the brain and records brain wave patterns (figure 1).
Doctors can usually tell if someone has CJD from the results of these tests. But a brain biopsy is the only test that can show for sure if someone has CJD. For the biopsy, a doctor removes a sample of brain tissue. Then, another doctor looks at the sample under a microscope. Most people do not need a brain biopsy. It is usually done when the doctor thinks a disease other than CJD might be causing the symptoms.
How is CJD treated? —
Sadly, there are no treatments to stop or cure the disease. The dementia keeps getting worse, and all people with CJD die within several months after their symptoms start.
If needed, doctors sometimes prescribe medicines to help calm down the person's behavior or to help with the muscle jerks.
Hospice programs can also be helpful. These provide "comfort care" and other services near the end of a person's life.
What if my family member has CJD? —
You need to make plans for the future. This includes making plans for their:
●Living situation – If your family member lives alone, it's important to make sure they are safe and have the help they need to take care of themselves. When they can't live alone, you need to decide whether they will live at home with help, or move to a nursing home.
●Decision-making – Early on, your family member should choose a "power of attorney." This is someone who can make decisions (including medical decisions) for them when they no longer can.
●Money – As the disease gets worse, your family member will be unable to manage their money.
●Driving – If your family member still drives, talk with the doctor about when they should stop.
Many people who get CJD can get disability payments through Social Security.
After the person has died, the doctor might ask about doing an autopsy. This can help confirm the diagnosis of CJD. Legally, doctors need to get permission from a relative to do an autopsy.
The Creutzfeldt-Jakob Disease Foundation has a lot of information for families and caregivers. Their website is www.cjdfoundation.org/for-families. Their toll-free phone number in the US is 1-800-659-1991.
Patient education: Dementia (including Alzheimer disease) (The Basics)
Patient education: Myoclonus (The Basics)
Patient education: Evaluating memory and thinking problems (The Basics)
Patient education: EEG (The Basics)
Patient education: Advance directives (The Basics)
Patient education: Medical care during advanced illness (The Basics)
Patient education: Time to stop driving? (The Basics)
Patient education: Dementia (including Alzheimer disease) (Beyond the Basics)
