Movement disorders reveal Creutzfeldt–Jakob disease
Posted Aug 04 2009 6:32pm
Movement disorders reveal Creutzfeldt–Jakob disease
Michael Weller and Adriano Aguzzi
Human prion diseases are sometimes difficult to diagnose because few clinical features distinguish them reliably from other neurological disorders. a new study suggests that analysis of movement disorders might contribute to the clinical differentiation of sporadic Creutzfeldt–Jakob disease from alzheimer disease and dementia with lewy bodies.
like other human prion diseases, Creutzfeldt– Jakob disease (CJD) causes progressive cognitive dysfunction resulting in dementia. in addition, most patients experience a spectrum of neurological disturbances, including symptoms and signs of motor system dysfunction (for example, myoclonic jerks and ataxia). Differentiating CJD from other dementias is problematic and no well-characterized surrogate markers exist for the disease. However, edler and colleagues1 recently determined the value of motor disturbances in the diagnosis of human prion diseases; the presence of ataxia and dysmetria, along with the absence of hypokinesia, suggested the presence of CJD rather than alzheimer disease (aD) or demetia with lewy bodies (DLB).
Pathogenic prions are misfolded molecules that can convert normal prion protein to the abnormally folded state, and this ability is thought to account for their infectious character. Prions cause a group of neuro logical diseases that affect humans and various animals. these diseases can be propa gated through iatrogenic transmission of the prion particles between individuals, or in experimental animal models through various routes of inoculation.2 Prion diseases are rare compared with their most important differential diagnoses, namely, aD and lB.3,4
Despite considerable progress in understanding prion disease patho genesis, unequivocal establishment of the CJD diagnosis from clinical and laboratory features (Box 1) during a patient’s lifetime has remained a challenge. the clinical triad of demen tia, ataxia, and myoclonus is con sidered characteristic of CJD. Diagnosis can also be circumstantially supported by eeG patterns referred to as ‘triphasic complexes’, and by the detection of proteins (for example, neuron-specific enolase and 14-3-3 protein), ‘leaked’ from injured neurons, in the patient’s cerebrospinal fluid. However, all the above surro - gate markers have limited specificity for prion disease. Potential alternative surrogate markers do exist, but they remain to be fully evaluated. these markers include the enzyme a1-antichymotrypsin, which can be detected in increased amounts both in brain tissue and in the urine of prion -infected animals,5 and the pathological prion protein (PrPsc) itself. the detection of PrPsc in body fluids— in the form of PrPsc aggregates6 or prion seeds7—is hoped to facilitate early diagnosis. 8,9 of note, familial forms of human prion diseases are more readily diagnosed than sporadic variants, because they are invariably associated with mutations in the prion protein gene, PRNP, and can be easily detected by Dna sequencing. most prion diseases, however, occur sporadically; familial forms account for
doi:10.1038/nrneurol.2009.32 Competing interests
The authors declared no competing interests.
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Transgenic mice expressing porcine prion protein resistant to classical scrapie but susceptible to sheep bovine spongiform encephalopathy and atypical scrapie. Emerg Infect Dis. 2009 Aug; [Epub ahead of print]
Monday, June 01, 2009 Biochemical typing of pathological prion protein in aging cattle with BSE
SOMETHING TO PONDER ???
O.K. confusious asks, IF all these new atypical BSEs i.e. new strains of mad cow disease is just an 'OLD COW PRION DISEASE', why then can not the 'old human prion disease' such as the sporadic CJD, be from an 'old cow prion disease', same as the nvCJD 'young people mad cow disease' (which also happens in 74 year old), but why cannot the 'old cow prion diseases', i.e. l-BSE, h-BSE, and ibncBSE, cause the 'old people prion disease', which looks like sporadic CJD. seems that is what some of the pathology is showing ???
OH, that probably makes too much sense, and that the only answer could be that it's all just a happenstance of bad luck and or a spontaneous event, that just happens out of the clear blue sky $$$
IF this is the case, then where are all the SPONTANEOUS BSE CASES OF MAD COW DISEASE IN THE U.S.A., AND WHERE HAVE THEY BEEN BURIED IN THE USA OVER THE LAST 25 YEARS ???