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CREUTZFELDT-JAKOB DISEASE
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Description
Creutzfeldt-Jakob disease (CJD) is a rare form of degenerative brain disorder that
destroys brain matter. This brain degeneration causes physical and psychotic symptoms,
eventually to the point of a coma and then ultimately death (NIH, 2014). Creutzfeldt-Jakob
disease is classed as a prion disease (See figure 1-1, page 7). This happens when a prion protein
that is present in the entire body folds into an abnormal shape. Eventually the abnormal shape of
the proteins causes proteins in the brain to mimic them and fold into the same shape. Due to the
abnormal shapes of the proteins they attack and destroy the brain leaving lesions on the brain
matter (See figure 1-2, page 7). This process then causes damage to areas of the brain that are
necessary for humans to function for day-to-day activities (Alzheimer, 2014). Some of the
symptoms that present in early stage are nervousness, behavior changes, vision problems, weight
loss, anxiety, fatigue, sleeplessness and headaches (Baron, 1996). There are three different
classifications of Creutzfeldt-Jakob disease. Sporadic CJD is when it occurs in a patient for no
known reason. Scientists are still hoping to figure out why this happens. Hereditary CJD is
when it is passed from generation to generation in families. This is passed down through a
dominant gene from a parent that is a direct carrier. Acquired CJD is when it is contracted from
direct contact with infectious tissue. This is the form of CJD that is the most rare. These cases
would be due to an oversight with a medical tissue transplant or a blood transfusion. Although
the symptoms are the same, they are all different in how the affected person has acquired this
disease (NIH, 2014). Creutzfeldt-Jakob disease occurs at a rate of in one in one million people
per year worldwide. Sporadic CJD makes up approximately eighty-five percent of these cases.
While Familial CJD makes up ten to fifteen percent and Acquired CJD only accounts for
approximately one percent of cases (Alzheimer, 2014).
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CREUTZFELDT-JAKOB DISEASE
Inheritance / development
Sporadic CJD is not known why it occurs (Alzheimer, 2014). Hereditary CJD is an
autosomal dominant inheritance. This gene mutation is passed on from the affected parent and
continues on to their children in the form of the dominant gene.
The chance of someone with
CJD passing this mutation on to their children is approximately fifty percent (Mastrianni, 2014).
Acquired CJD is contracted from a medical surgery, tissue/organ transplant or growth hormone
injections. There is a small transmission for this form of CJD (NIH, 2014).
Effects of the disorder / diagnosis
In the early stages you may see memory loss, changes in mood or behavior, poor
coordination and vision difficulties. During the progression of CJD the patients mental capacity
decreases, involuntary movements of muscles that can include the entire limb, blindness can
occur, weak extremities and then eventually coma and death (NIH, 2014). Some patients can
also have psychiatric symptoms, seizures, stroke-like episodes and interruption of the autonomic
nervous system. As the symptoms increase there is an increase in spongiform degeneration and
increased lesions (Mastrianni, 2014). Symptoms that are increasing in intensity would be one of
the most important signs that someone may have CJD. There is no way to conclusively diagnose
CJD in a living person. After doctor has ruled out all other possible forms of dementia such as
encephalitis or chronic meningitis. There are three tests that can help to diagnose someone who
is suspected of having CJD. The electroencephalogram (EEG) is used to measure the brain’s
electrical activity the same way that electrocardiogram (ECG) is used to measure the electrical
activity in a patient’s heart (See figure 1-3, page 7). As well, brain magnetic resonance imaging
(MRI) can also detect changes in the brain that are consistent with CJD patients. The last way is
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a lumbar puncture (spinal tap) this is done to check the spinal fluid of a patient in order to detect
the presence of certain proteins (Alzheimer, 2014). To determine whether the same agent caused
the infection, scientists had infected patients in different countries tested samples of four patients
from the Netherlands, Italy, France and the United States. The strain typing analysis used a
standard panel and each sample was methionine homozygous at codon 129 of the prion gene.
None of the patients had received any organ donations or blood transfusions. Autopsies were
used after death to confirm the diagnosis (Diack et al, 2012).
Current treatments
Currently there are no treatments to cure or control CJD. Patients are made comfortable
and treated with medications to mask their symptoms. Opiate drugs are widely used like
clonazepam and sodium valproate (NIH, 2014). The best form of treatment for Acquired CJD is
prevention. By decontaminating and sterilization of surgical instruments and biologic materials
and transplantation tissues you can reduce the risk of infection (Baron, 1996).
Life expectancy / prognosis
After the onset / diagnosis of any signs of CJD it is very likely that the patient will die
within six months to fourteen months, ninety percent of patients die with in one year (Alzheimer,
2014). There have been no reported cases where a patient was diagnosed with CJD and was
cured, treated successfully or survived. Creutzfeldt-Jakob disease will always be fatal in the end
due to the degeneration of the brain matter which in necessary to sustain life. It is generally a
disease that affects mostly males and there have been no cases ever reported of a pregnant
woman having or contracting this disease (Institute of medicine, 2006). In the United States,
Europe, Australia, South America and Asia there are between one to two deaths per million per
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year. There has been occasional clustering of non-familial cases in small towns and rural areas
with in Israel, Hungary, England, Czechoslovakia and Chile (Baron, 1996).
Current research
Quinacrine an antimalarial agent was tested in clinical trials and found unsuccessful in
providing any benefits or prolonged life to patients with CJD. There are a few therapies being
tested on animals, for example antibodies against precursor proteins (PrP), gene silencing with
RNA inhibitors, and anti-amyloids (Mastrianni, 2014). Researchers are using rodents that are
infected with CJD and brain tissue from autopsies to try to identify the factors that can cause
CJD to show up later in life after lying dormant in the body during the earlier years (NIH, 2014).
In the mid-1980s there was an outbreak of mad cow disease (BSE), which is a prion disease that
is present in cows, and this woke the world up to the dangers of prion disease. Creutzfeldt-Jakob
disease is a type of prion disease that affects humans in the same manner. There was a study
done then on mice that had been genetically engineered to resemble cattle in a metabolic way.
They injected some mice with BSE from cattle and some with CJD from people and the resulting
disease looked the same. The prion disease in both species looked and acted the alike, both of
them showing similar results approximately two hundred and fifty days after injection into the
rodents (Institute of medicine, 2006).
Conclusion
Although scientists are still searching for answers there seems to be no cure or treatment
in sight for Creutzfeldt-Jakob disease. This rare and degenerative disease attacks people without
warning either by transmission or lying dormant with in the body. Many tests and assumptions
can be made in order to try to diagnose a patient thought to have CJD. Conclusive diagnosis is
only reached after the patient has expired and a post mortem autopsy is performed and the brain
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matter has been inspected. Destruction of brain matter with the forming of lesions leads to some
difficult and uncomfortable effects for the patient. This would have a large impact on the lives
of the families as well as the patients. This would require patients to be cared for around the
clock and closely monitored by their doctors. Patients would require treatment management with
opioids to east the pain and suffering. From onset to diagnosis to death is thankfully short, the
amount of time totaling approximately around one year. More information is required in order to
someday find a cure for this disease. It is a terrible way to die and hopefully with medical
research something can be found to cure it and help to change the way it mutates and destroys
patient’s brains.