Creutzfeldt-Jakob disease (CJD)

Creutzfeldt-Jakob disease (say "CROITS-felt YAH-kob"), or CJD, is a rare brain disease. It causes a dementia that gets worse very quickly, often over weeks to a few months instead of years.^1,2 There is no cure, and it is always fatal.²

If someone you love may have CJD, this page explains how doctors test for it, whether family members are at risk, and how to focus on comfort in the time you have.

What is CJD?

CJD is the most common human prion disease.³ A prion is a protein that has folded into the wrong shape. Everyone has normal prion protein, mostly in the brain and nerves. A misfolded prion can make healthy prion proteins fold the wrong way too. They clump together and kill brain cells.¹

As brain cells die, the brain tissue fills with tiny holes. Under a microscope it looks like a sponge. That is why doctors also call these illnesses spongiform encephalopathies (sponge-like brain diseases).¹

Unlike Alzheimer's, which unfolds over years, CJD can change a person from week to week. This speed is one of the most important clues doctors use.³

The types of CJD

Sources for the table: CDC and NINDS.^1,2,4

Acquired CJD came mostly from human growth hormone made from donor glands and from brain covering (dura mater) grafts. No case from surgical tools has been reported since 1976.⁸

Variant CJD is a separate illness. Only 233 cases have been reported worldwide since 1996, mostly in the United Kingdom. All four U.S. cases are thought to have been caught abroad.⁴ Classic CJD, the kind most older adults get, is not caused by eating beef.²

Signs and symptoms

Early signs can be mistaken for a stroke, depression or another illness. Early on, a person may have:^1,3

• Confusion and memory problems that get worse quickly
• Poor judgment or trouble planning
• Mood or behavior changes, such as depression, agitation or not caring about things
• Trouble with balance, walking or coordination
• Vision changes, such as double vision, or seeing things that are not there (hallucinations)
• Trouble speaking, sleep changes, dizziness or shaking

As the disease moves on, many people get sudden, jerky muscle movements called myoclonus. Many people also become very sensitive to sudden touch or loud noise.^1,10 Later, a person may lose sight, become unable to move or speak, and have trouble swallowing. Many become fully dependent on others. Some fall into a coma. The risk of infections such as pneumonia goes up.^1,3

Genetic and variant CJD often start earlier in life and last somewhat longer than sporadic CJD.^3,4 Variant CJD often begins with depression, anxiety or withdrawal before memory problems appear.⁴

How fast does CJD progress?

For sporadic CJD, the middle point (median) from first symptoms to death is about 4 to 5 months.² About 7 in 10 people die within a year of diagnosis.¹ A smaller number live longer, especially with genetic forms.³

Because time can be so short, families often must make care, money and legal decisions within weeks. Start planning right away if you can.

How doctors find out it is CJD

No one test proves CJD in a living person with 100% certainty.³ Doctors combine an exam with several tests. They also look hard for treatable illnesses that can look like CJD, such as autoimmune brain inflammation, infections or some cancers. Our page on dementia that gets worse fast explains these.

1. Neurological exam. The doctor checks reflexes, muscle twitching, coordination and vision.¹
2. Brain MRI. A brain scan shows typical changes in about 9 out of 10 people with CJD.¹
3. EEG. This test records brain waves with small pads on the scalp. In some types of CJD, it shows a telltale repeating pattern.^1,2
4. Spinal fluid tests. A lumbar puncture (spinal tap) takes a small sample of the fluid around the brain and spine. Proteins called 14-3-3 and tau show that brain cells are dying fast, but they can also rise in other illnesses.¹
5. RT-QuIC. This newer test, run on the same spinal fluid, looks for the misfolded prions themselves. It is much more specific to CJD.¹

What the RT-QuIC test means in plain numbers

RT-QuIC (real-time quaking-induced conversion) mixes a little spinal fluid with normal prion protein in a lab. If misfolded prions are present, they make the normal protein misfold too, and the machine detects it.

In a large U.S. study, the test found about 93% to 95% of people who had sporadic CJD. That is about 19 out of 20. It was positive in very few people who did not have a prion disease. In one group of patients, that never happened at all (100% specificity).⁵

So a positive RT-QuIC result is strong evidence. A negative result does not fully rule CJD out, because the test misses about 1 in 20 cases.⁵ Under CDC criteria, a positive RT-QuIC plus typical symptoms counts as probable CJD.²

A diagnosis is called definite only when brain tissue is examined, by brain biopsy or after death.^1,2 Brain biopsy is now rarely done. It carries risks and is mainly used when doctors need to rule out a treatable disease.^1,6 This is why many families choose a brain autopsy later (see below).

Is there any treatment?

No medicine has been shown to slow or stop CJD.^1,3 Care focuses on comfort and on easing symptoms. Doctors may prescribe medicines for muscle jerks, seizures, pain, muscle stiffness or upsetting behavior changes.^1,3 Talk with the doctor or hospice team before changing or stopping any medicine.

Researchers are studying how prions form and spread, and an early-stage clinical trial is testing a way to lower the body's prion protein.¹ This work is not proven. To explore research, ask the neurologist or see joining a dementia clinical trial. Be wary of any clinic that sells an unproven "cure."

Can family members catch it?

No. CJD does not spread through the air, through touch or through everyday contact.^1,7 There is no sign of higher risk for family caregivers, health care workers or people who prepare bodies for funerals.¹ You do not need special precautions to hug, feed, bathe or sit with your loved one.⁷ As with any patient, wear gloves if you might touch their blood.⁷

The risk that does exist is in surgery. The brain, spinal cord and eyes carry the most prions.⁸ Make sure every hospital, surgeon and eye doctor knows the diagnosis. They use special cleaning steps for any tools that touch these tissues.¹

Focusing on care and comfort

Needs can change in days. These steps help you stay ahead.

1. Call hospice right away. Do this even if you do not need them yet. Hospice can keep your loved one comfortable and adjust care as things change.^7,10 Medicare covers hospice. See hospice care for dementia and palliative care.
2. Decide where care will happen. Home, a relative's home, an inpatient hospice or a care facility can all work. Ask who will check in each day, and whether the person can safely be left alone.¹⁰ Most people with advanced CJD need care around the clock.³
3. Build a care schedule. Set up shifts with family and friends. Consider hiring home health aides.¹⁰ Our care circle tool can help you divide tasks.
4. Get equipment early. Ask hospice about a hospital bed, shower chair or other equipment before a crisis.¹⁰
5. Handle legal papers fast. If the person can still take part, sign a power of attorney and an advance directive now.
6. Apply for benefits if eligible. Social Security lists CJD as a "Compassionate Allowance," which can speed up a disability claim.^6,3 See Social Security disability.

Day-to-day comfort tips

Brain autopsy: why families choose it

A brain-only autopsy after death is the only way to confirm CJD for certain. It also shows the exact cause and subtype, which can matter for other family members. Donated tissue helps researchers worldwide.¹¹

The National Prion Disease Pathology Surveillance Center, supported by CDC, arranges these autopsies free of charge for U.S. cases. It covers the autopsy, transport and CJD testing, but not funeral costs.^11,2

• How to start: Call the Center at 216-368-0587 (weekdays 9:00 a.m. to 4:30 p.m.) and ask for an autopsy coordinator. For a death at night or on a weekend, call 216-647-8148.¹¹
• Consent: The legal next of kin signs a consent form.¹¹ You can call ahead of time to learn the steps and get the form ready.
• Funeral plans: The autopsy usually does not delay the funeral. There is no medical reason to rule out embalming or an open casket, though each funeral home decides. The coordinators can help talk with the funeral home.¹¹
• Results: Final results go to the doctors named on the form, usually about three months later. The doctor then shares them with you.¹¹

Support for you

Watching someone change this fast is very hard. You may grieve while your loved one is still here. See grieving someone still here and caregiver stress and burnout.

• CJD Foundation HelpLine: 1-800-659-1991, open 7 days a week. It offers information, support groups and a caregiving guide.^12,10
• Alzheimer's Association 24/7 Helpline: 1-800-272-3900, for information and local services.³

Common questions

Is CJD the same as mad cow disease?

No. Mad cow disease affects cattle. Eating infected beef caused a rare, separate illness called variant CJD, mostly in the United Kingdom.⁴ Classic CJD, which is far more common in older adults, is not linked to mad cow disease.²

Did something we did cause this?

Almost certainly not. About 85 in 100 cases are sporadic, with no known cause.² It is not caused by anything you or your loved one did.

Can we still hug and kiss our loved one?

Yes. Everyday contact, including touching, hugging and kissing, does not spread CJD.^1,7 After death, if an autopsy was not done, there is no need to avoid touching or kissing the face. If an autopsy was done, CDC advises families not to touch or kiss the face.⁸

When to get help

Education only. This page is general information written from the sources listed. It is not medical, legal or financial advice and does not replace a doctor, therapist or lawyer who knows your situation. How we write and check pages.