Creutzfeldt-Jakob disease

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at October 19, 2016
StartDiseasesCreutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is a rare disease that only afflicts about one in a million people worldwide, and only a handful of people in the United States. It most often afflicts people who are in late middle age or who are elderly.

The course of the disease is usually fast, and most people who contract Creutzfeldt-Jakob disease die within a year after they are diagnosed. The disease was discovered around 1920 by Hans Gerhard Creutzfeldt and Alfons Maria Jakob, both German neurologists.

Contents

Definition & Facts

Creutzfeldt-Jakob disease is a degenerative disease that attacks the brain and causes a type of dementia similar to Alzheimer's disease. It is a type of transmissible spongiform encephalopathy. This means that when the brain is autopsied, it is so full of holes that it resembles a sea sponge. As of 2016, there is no cure for Creutzfeldt-Jakob disease, and treatment is palliative.

Medical experts recognize three types of Creutzfeldt-Jakob disease: sporadic, hereditary and acquired.

  • Sporadic CJD afflicts a patient who has no risk factors for the disease. Most people who suffer from CJD have this type. Some patients who are diagnosed with this type of CJD live for only months or even weeks.
  • Acquired CJD is caused when the person comes into contact with tissue from a central nervous system infected with CJD. This type of the disease is very rare. It can be acquired when a person receives a corneal transplant from an infected person or from surgical instruments that have been used on a CJD patient and not properly sterilized. Other people get the disease when they receive grafts of infected dura mater. This is a tough membrane that covers the brain.
  • In hereditary CJD, the patient has a genetic predisposition towards getting CJD. This is also rare, though not as rare as acquired CJD.

CJD is not transmitted through casual contact.

Symptoms & Complaints

The first symptoms of CJD are insidious and include clumsiness, memory loss and disorders in cognition. Some people become depressed, notice changes in their personality or find that they have trouble sleeping. As the disease progresses, so does their mental impairment.

Patients become subject to seizures and lose their vision. Some patients are subject to odd, inexplicable sensations or hallucinations. They also become psychotic, or out of touch with reality. Eventually, CJD patients become paralyzed, then comatose. This is followed by death.

In some variants of CJD, the symptoms that lead to death persist for a longer time than in traditional CJD. These variants tend to strike younger people, and the patient's deterioration sometimes takes years.

Causes

CJD is caused by some kind of pathogen. Some medical professionals believe it is caused by a type of "slow" virus even though this virus has not yet been isolated. Whatever type of virus causes CJD, it seems to have an incubation period of as long as half a century. It is not known exactly how it works, for it does not seem to have any genetic material.

There is a strong indication that CJD isn't caused by a virus but by a prion, which is a type of protein. Prions are found naturally in the central nervous system and are mostly harmless. Scientists believe that the prions that cause CJD become abnormal, folding up in a pathological way and causing other prions to fold up. They then clump together to form bodies called amyloids and destroy the brain. Still, researchers do not know exactly how the prions do this or why. Some researchers also believe that damaged prions can be passed from the meat of an infected animal into a human, though this is controversial.

Prions also play a role in the patient who has a genetic mutation that leads to CJD. The genetic mutation tells the body to produce abnormal prions that then clump together and attack the brain. This mutation can be passed down from generation to generation.

Diagnosis & Tests

As with Alzheimer disease, there's no diagnostic test for CJD. Only an autopsy of the brain can definitively tell a doctor if the person has CJD. Some doctors take brain biopsies, but these procedures are risky and do not necessarily come from the part of the brain that is afflicted.

Doctors must rule out other brain diseases before they can be somewhat certain that the patient has CJD. This means the patient may need to undergo such tests as spinal taps, EEGs, MRIs, and CT scans to rule out such problems as encephalitis or brain tumors. MRIs seem to be more helpful than other tests because they can detect certain patterns that point to CJD. Diffusion weighted imaging may be even better at detecting brain abnormalities that suggest CJD.

Treatment & Therapy

There is no treatment or therapy that can cure or even slow down the course of CJD, even though batteries of drugs such as doxorubicin and amphotericin B have been tried. The only thing to be done is to make the patient comfortable and give them pain medications if they need it. Anti-seizure medications are also useful. At the end stage of the disease the patient will need round-the-clock nursing care. They will need tube feeding, catherization and frequent moving to prevent pressure sores.

Prevention & Prophylaxis

Though contracting the disease is exceedingly rare, people who suspect they have CJD or who have the mutated gene that can cause CJD should avoid donating blood or becoming organ donors. This is especially true if they are considering donating their corneas, for the eye is actually part of the brain. They should also not donate human growth hormone harvested from their pituitary glands, which is found in the brain. Men who suspect that they have CJD or the mutation that leads to it should not donate sperm.

Medical professionals should use standard safety procedures when treating people with CJD. This includes sterilizing or even destroying all tools that come into contact with the patient, wearing disposable gloves, gowns and surgical face masks when coming into contact with these patients.