Creutzfeldt-Jakob disease

Answer 1

Definition

Creutzfeldt-Jakob disease (CJD) is a form of brain damage that leads to a rapid decrease of mental function and movement.

Alternative Names

Transmissible spongiform encephalopathy; vCJD; CJD; Jacob-Creutzfeldt disease

Causes, incidence, and risk factors

CJD is believed to result from a protein called a prion. A prion causes normal proteins to fold abnormally. This affects the other proteins' ability to function.

There are several types of CJD. The disorder is very rare, occurring in about 1 out of 1 million people. It usually first appears between ages 20 and 70, with average age at onset of symptoms in the late 50s.

CJD can be grouped into classic or new variant disease.

The classic types of CJD are:

• Sporadic CJD makes up the majority of cases. It occurs for no known reason. Average age at onset is 65
• Familial CJD results when a person inherited the abnormal prion (inherited CJD is rare)

Classic CJD is not related to mad cow disease (bovine spongiform encephalitis).

However, new variant CJD (nvCJD) is an infectious form that is related to mad cow disease. The infection responsible for the disease in cows is believed to be the same one responsible for vCJD in humans.

New variant CJD accounts for less than 1% of cases, and tends to affect younger people. It can result when someone is exposed to contaminated products. Other nvCJD cases have occurred when people were given corneal transplants from infected donors, and from contaminated electrodes that were used in brain surgery (before it was known how to properly disinfect instruments).

There have not been any cases of nvCJD reported in the U.S.

CJD may be related to several other diseases also thought to be caused by prions, including kuru (seen in New Guinea women who ate the brains of deceased relatives as part of a funerary ritual), scrapie (found in sheep), chronic wasting disease (found in deer), and other rare human diseases, such as Gerstmann-Straussler-Scheinker disease and fatal familial insomnia.

Symptoms

• Rapidly developing delirium or dementia (over the course of a few weeks or months)
• Blurred vision (sometimes)
• Changes in gait(walking)
• Hallucinations
• Lack of coordination (for example, stumbling and falling)
• Muscle twitching
• Muscle stiffness
• Myoclonic jerks or seizures
• Nervous, jumpy feelings
• Personality changes
• Profound confusion, disorientation
• Sleepiness
• Speech impairment

CJD is rarely confused with other types of dementia (such as Alzheimer's disease) because in CJD, symptoms progress much more rapidly. Both forms of CJD are distinguished by extremely rapid progression from onset of symptoms to disability and death.

Signs and tests

Early in the disease, a neurological and mental status examination will show memory problems and changes in other mental functions. Later in the course of the disease, a motor system examination will show muscle twitching and spasm, a strong startle response, and an increase in muscle tone. There may also be weakness and loss of mucle tissue (muscle wasting) and abnormal reflexes or increased normal reflex responses.

There is loss of coordination related to visual-spatial perception changes and changes in the cerebellum, the area of the brain that controls coordination (cerebellar ataxia). An eye examination shows areas of blindness that the person may not realize are present.

Tests used to diagnose this condition may include:

• Brain MRI
• EEG
• Spinal tap
• Blood tests to rule out other forms of dementia and to look for markers that sometimes accompany the disease

Ultimately, the disease can only be confirmed by brain biopsy or autopsy.

Treatment

There is no known cure. Interleukins and other medications may be use in an attempt to slow the progression of the disease. Custodial care may be required early in the course of the disease. Medications may be needed to control aggressive behaviors.

Provding a safe environment, controlling aggressive or agitated behavior, and meeting physiologic needs may require monitoring and assistance in the home or in an institutionalized setting. Family counseling may help in coping with the changes required for home care.

Visiting nurses or aides, volunteer services, homemakers, adult protective services, and other community resources may be helpful in caring for the person with CJD.

As with other illnesses that cause dementia, behavior modification may be helpful, in some cases, for controlling unacceptable or dangerous behaviors. This consists of rewarding appropriate or positive behaviors and ignoring inappropriate behaviors (within the bounds of safety). Reality orientation, with repeated reinforcement of environmental and other cues, may help reduce disorientation.

Legal advice may be appropriate early in the course of the disorder to form advance directives, power of attorney, and other legal actions that may make it easier to make ethical decisions regarding the care of an individual with CJD.

Expectations (prognosis)

The outcome is usually very poor. Within 6 months or less of the onset of symptoms, the person will become incapable of self-care.

The disorder is fatal in a short time, usually within 8 months, but a few people survive as long as 1 or 2 years after diagnosis. The cause of death is usually infection, heart failure, or respiratory failure.

Complications

• Infection
• Heart failure
• Respiratory failure
• Loss of ability to function or care for oneself
• Loss of ability to interact with others
• Death

Calling your health care provider

CJD is not a medical emergency, but early diagnosis and treatment may make the symptoms easier to control, allow patients time to make advance directives, and give families additional time to come to terms with the condition.

Prevention

Medical equipment is sterilized to kill organisms that may cause the disease. Persons who have a medical history of diagnosed or possible CJD are not used as cornea donors.

Most countries now have strict guidelines for management of infected cows and strict restrictions regarding what they are fed, to avoid the potential for transmission of CJD to humans.

References

Zeidler M. Prion diseases. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier. 2007: chap 442.

Answer 2

Definition

Creutzfeldt-Jakob disease (CJD) is a form of brain damage that leads to a rapid decrease of mental function and movement.

Alternative Names

Transmissible spongiform encephalopathy; vCJD; CJD; Jacob-Creutzfeldt disease

Causes, incidence, and risk factors

CJD is thought to be caused by a protein called a prion. A prion causes normal proteins to fold abnormally. This affects the other proteins' ability to function.

There are several types of CJD. The disorder is very rare, occurring in about 1 out of 1 million people. It usually first appears between ages 20 and 70. Symptoms usually start in the late 50s.

CJD can be grouped into two types: classic or new variant disease.

The classic types of CJD are:

• Sporadic CJD makes up most cases. It occurs for no known reason. The average age at which it starts is 65.
• Familial CJD occurs when a person inherits the abnormal prion from a parent (inherited CJD is rare)

Classic CJD is not related to mad cow disease (bovine spongiform encephalitis).

However, variant CJD (vCJD) is a form of the disease that is related to mad cow disease. The infection that causes the disease in cows is believed to be the same one that causes vCJD in humans.

Variant CJD accounts for less than 1% of cases, and it tends to affect younger people. However, fewer than 200 people worldwide have had this disease.

Variant CJD can be caused by exposure to contaminated products. Other vCJD cases have occurred when people were given corneal transplants, other tissues, or blood transfusions from infected donors. It may also have been caused by contaminated electrodes used in brain surgery (before instruments started to be properly disinfected).

There have not been any cases of vCJD reported in the U.S.

CJD may be related to several other diseases caused by prions, including:

• Chronic wasting disease (found in deer)
• Kuru (seen in New Guinea women who ate the brains of dead relatives as part of a funeral ritual)
• Scrapie (found in sheep)
• Other rare human diseases, such as Gerstmann-Straussler-Scheinker disease and fatal familial insomnia

Symptoms

• Blurred vision (sometimes)
• Changes in gait(walking)
• Confusion, disorientation
• Dementia that occurs over a few weeks or months
• Hallucinations
• Lack of coordination (for example, stumbling and falling)
• Muscle stiffness
• Muscle twitching
• Myoclonic jerks or seizures
• Nervous, jumpy feelings
• Personality changes
• Sleepiness
• Speech impairment

CJD is rarely confused with other types of dementia (such as Alzheimer's disease) because in CJD, the symptoms get worse much more quickly. Both forms of CJD are different than dementia because the symptoms progress quickly to disability and death.

Signs and tests

Early in the disease, a nervous system and mental examination will show memory problems and changes in other mental functions. Later in the disease, a motor system examination may show:

• Abnormal reflexes or increased normal reflex responses
• Increase in muscle tone
• Muscle twitching and spasms
• Strong startle response
• Weakness and loss of muscle tissue (muscle wasting)

There is loss of coordination and changes in the cerebellum, the area of the brain that controls coordination (cerebellar ataxia). An eye examination shows areas of blindness that the person may not notice.

Tests used to diagnose this condition may include:

• Blood tests to rule out other forms of dementia and to look for markers that sometimes occur with the disease
• CT scan of the brain
• Electroencephalogram(EEG)
• MRI of the brain
• Spinal tap to test for a protein called 14-3-3

The disease can only be confirmed with a brain biopsy or autopsy.

Treatment

There is no known cure for this condition. Interleukins and other medications may help slow the disease. The person may need care early in the disease. Medications may be needed to control aggressive behaviors.

Providing a safe environment, controlling aggressive or agitated behavior, and meeting the person's needs may require monitoring and assistance in the home or in a care facility. Family counseling may help the family cope with the changes needed for home care.

Visiting nurses or aides, volunteer services, homemakers, adult protective services, and other community resources may help care for the person with CJD.

People with this condition may need help controlling unacceptable or dangerous behaviors. This involves rewarding positive behaviors and ignoring negative behaviors (when it is safe). They may also need help getting oriented to their surroundings.

Getting legal help with advance directives, powers of attorney, and other legal actions early in the disorder can make it easier to make ethical decisions about the CJD patient's care.

Expectations (prognosis)

The outcome of CJD is usually very poor. Within 6 months or less after symptoms begin, the person will be unable to care for himself or herself.

The disorder is fatal in a short time, usually within 8 months. However, a few people survive for as long as 1 or 2 years. The cause of death is usually infection, heart failure, or respiratory failure.

Complications

• Infection
• Loss of ability to interact with others
• Loss of ability to function or care for oneself
• Death

Calling your health care provider

CJD is not a medical emergency. However, getting diagnosed and treated early may make the symptoms easier to control, give patients time to make advance directives, and give families extra time to come to terms with the condition.

Prevention

Medical equipment should be treated to remove the proteins that may cause the disease. People who have a history of CJD should not donate a cornea or tissue.

Most countries now have strict guidelines for managing infected cows to avoid transmitting CJD to humans.

References

Bosque PJ. Prion diseases. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 424.

DeKosky ST, Kaufer DI, Hamilton RL, Wolk DA, Lopez OL. The dementias. In: Bradley WG, Daroff RB, Fenichel GM, Jankovic J, eds. Neurology in Clinical Practice. 5th ed. Philadelphia, Pa: Butterworth-Heinemann Elsevier; 2008:chap 70.

Reviewed By

Review Date: 09/26/2011

David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by Luc Jasmin, MD, PhD, Departments of Anatomy and Neurological Surgery, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.