It's called Creutzfeldt Jakob Disease in humans
below is from
http://cjdfoundation.org/CJDInfo.html
Copyright 1999 Creutzfeldt-Jakob Disease Foundation, Inc. All rights reserved.
What Are The Symptoms of Creutzfeldt-Jakob Disease?
There are several common symptoms evident in CJD patients as the disease runs its course. The average duration of CJD from the onset of symptoms to the inevitable death is four to six months. Most patients die within one year; however, longer duration periods of two or more years have been noted, usually in the familial form and with an earlier age of onset.
The initial stage of the disease can be subtle with ambiguous symptoms of insomnia, depression, confusion, personality and behavioral changes, strange physical sensations, and problems with memory, coordination and sight. As the disease advances, the patient experiences a rapidly, progressive dementia and in most cases, involuntary and irregular jerking movements known as myoclonus. Problems with language, sight, muscular weakness, and coordination worsen. The patient may appear startled and become rigid. In the final stage of the disease, the patient loses all mental and physical functions. The patient may lapse into a coma and usually dies from an infection like pneumonia precipitated by the bedridden, unconscious state.
How Is Creutzfeldt-Jakob Disease Diagnosed?
A diagnosis of CJD should be considered when an adult patient develops a rapid dementia and myoclonus. Unfortunately, confirming a diagnosis of CJD has historically been difficult as traditional laboratory tests have been ineffective in detecting CJD. The disease does not induce a fever or other systemic manifestations. Presently, there is no single test for diagnosing CJD. If CJD is suspected, the first step is usually to exclude the possibility that other treatable illnesses are causing the troubling symptoms.
The most helpful test traditionally has been the electroencephalogram ("EEG"), which measures brain wave activity. The EEG often shows a characteristic abnormal pattern, typically observed in later stages of the disease, but the EEG does not confirm a CJD diagnosis. Additionally, a computed tomography ("CT") brain scan is usually normal, but , as the disease progresses, may show some atrophy, a nondiagnostic finding seen in many other neurological conditions.
Recently, more tests have been identified as valuable tools for diagnosing CJD. Scientists have developed a test to detect the 14-3-3 protein in the cerebrospinal fluid. The 14-3-3 test has proved to be a useful aid in diagnosing CJD, but does not, by itself, provide a definitive diagnosis of CJD. A false positive rate of five to ten per cent has been attributed to the test. Likewise, magnetic resonance imaging (âMRIâ) brain scans may be providing another form of assistance in diagnosing CJD when they reveal hyperintense signals in the basal ganglia on T2-weighted images. Blood tests for the genetic mutations associated with familial prion diseases provide further means for diagnosing CJD.
A definitive diagnosis of CJD has traditionally required a brain biopsy or autopsy which can detect the characteristic changes in the brain tissue caused by the disease. Because these procedures are costly and pose risks to those handling the brain tissue, they are not always performed. Other factors discouraging the performance of brain biopsies include: the invasiveness of the procedure; the risk of a false-negative result if the biopsied area was unaffected by the disease; and, the lack of benefit to the patient from a correct CJD diagnosis since the disease is invariably fatal. Accordingly, brain biopsies are usually advisable only when required to exclude a treatable condition. Nevertheless, the examination of suspect brain tissue is essential to the proper monitoring and research of CJD and other TSEâs. Following specific guidelines developed by TSE experts for sterilization and infection control can minimize risks associated with brain biopsies and autopsies. The National Prion Disease Pathology Surveillance Center can provide guidance and assistance for performing autopsies and brain biopsies, as well as tests for the 14-3-3 protein, mutation in the prion protein gene, and complete diagnostic studies.
The difficulties involved in diagnosing CJD may have prevented the identification of the disease in some cases. Since the disease progresses rapidly, the patient may die before a diagnosis can be made. Furthermore, some physicians may not even consider the possibility of a CJD diagnosis because the disease is deemed to be rare and the clinical symptoms of CJD can often be attributed to other ailments. Consequently, CJD may be mistaken for a variety of psychological illnesses and other neurological disorders like Alzheimer's Disease, Pick's Disease, Huntington's Disease, cerebral hematomas and vascular irregularities. The extent to which such misdiagnosis may have occurred is presently unknown.
Copyright 1999 Creutzfeldt-Jakob Disease Foundation, Inc. All rights reserved.
