CJD, or Creutzfeldt-Jakob disease, is a rare degenerative brain disorder that leads to dementia and eventual death. CJD occurs in one out of every 1 million people, according to the University of Maryland Medical Center. CJD is believed to be caused by an abnormal protein known as a prion that causes other proteins to collapse abnormally, decreasing their ability to function. There are two types of CJD; symptoms are often similar but can often be differentiated by which symptoms present first.
Types
Classic CJD dates back to the early 1920s, according to the U.S. Centers for Disease Control and Prevention, and is a human prion disease. This disease is a rapidly progressing disease and is always fatal. Another type of CJD is variant CJD. Variant CJD was first noticed in 1996 in the United Kingdom and stems from a different type of prion. Varient CJD is associated with bovine spongiform encephalopathy, more commonly known as "mad cow" disease. This type of CJD is infectious and can afflict humans.
Symptoms
People with either classic or variant CJD often experience similar symptoms, though the timeline may vary. People with CJD will experience a rapid deterioration in mental function including delirium, dementia, profound confusion, speech impairment, sleepiness, nervousness and blurred vision. People will also experience changes in gait, lack of coordination, muscle twitching, muscle stiffness and myoclonic jerks or seizures, according to the University of Maryland Medical Center. In classic CJD, people are more likely to exhibit neurological signs first. In variant CJD, patients will often present with painful muscle twitches as well as prominent psychiatric and behavioral symptoms.
Time Frame
The difference between classic CJD and variant CJD is largely in the rate of disease progression. The CDC explains that in classic CJD, there is only a four to five month span between onset of symptoms and death. Variant CJD often spans 13 to 14 months from beginning symptoms to death.
Effects
CJD belongs to a group of diseases known as transmissible spongiform encephalopathies, according to MayoClinic.com. The spongiform name comes from the spongy holes visible in the affected brain tissue under a microscope. As the brains tissues deteriorate, the patient's symptoms become more severe until death is inevitable.
Transmission
Classic CJD often occurs with no obvious reason. This is known as spontaneous or sporadic CJD. In a small number of cases, about 5 to 10 percent in the United States, people who develop CJD have a history of the disease and test positive for a genetic mutation. This is referred to as familial CJD. Variant CJD primarily occurs from eating beef infected with bovine spongiform encephalopathy, or mad cow disease, according to MayoClinic.com.
