Discuss Regarding The Manifestations And Pathogenesis Of Sporadic, Acquired And Inherited/familial Prion Diseases.

[ADVANCED VIROLOGY] MFEB 3401 CONASS 27TH AUGUST 2008 Discuss regarding the manifestations and pathogenesis sporadic, acquired and inherited/familial prion diseases.

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Infectious disease of prion were existing through the genomes. There also called Transmissible Spongiform Encephalopathies (TSEs) where it can be characterized by a rare group of infectious agent by showing a ‘slow diseases’. The ‘slow diseases’ is a term for reffering the long incubation periods of time without clinical symptoms. Furthermore, the prion were have biological and physicochemical characteristics which differ to other microorganisms. Most of these disease can cause fatal with neurodegenerative, where it affected on both human and animals. Table below shown a listed of Transmissible Spongiform Encephalopathies on human and animals : TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES DISEASES OF ANIMALS Bovine spongiform encephalopathy (BSE / Mad Cow Disease) Chronic Wasting Disease (CWD) : Deer and Elk Exotic Ungulate Encephalopathy (EUE) : Nyala and Greater Kudu Feline Spongiform Encephalopathy (FSE) : Domestic and Great Cats Scrapie in Sheep and Goats Transmissible mink encephalopathy (TME) TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES DISEASES OF HUMANS Creutzfeldt-Jakob Disease (CJD) Fatal Familial Insomnia (FFI) Gerstmann-Straussler Syndrome (GSS) Kuru Variant CJD (vCJD) About 1% are diagnosed with spongiform encephalopathies. However, this may be increased due to spreading of some TSEs by animals. William Hadlow studies had demonstrated that scrapie and kuru disease can be transmitted from human to chimpanzee and other primates. On the year 2002, about 120 individual were causes dead from variant Creutzfeldt-Jakob disease. Kuru disease were also been reported to causes dead among the Fore people of New Guinea. These happen as result of their ritual cannibalism by eating brain of their deceased relatives. Human TSEs disease are divided into three classes; sporadic,

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[ADVANCED VIROLOGY] MFEB 3401 acuired and familial, where it distinguished by how the disease is initially acquired. In the classess of sporadic are the disease that appears no epidemiological indication, which means happen without warning. In such Creutzfeldt-Jakob disease were shown affecting to million individuals in average life range of 50 to 70 years old (1).

The initial symptoms in about a third of cases are systemic complaints of fatigue, disordered sleep, and decreased appetite; about a third of patients present with behavioural or cognitive changes; and the final third have focal signs such as visual loss, cerebellar ataxia, aphasia, or motor deficits (2). Kuru disease were also been reported to be sporadic since it was established at small population of Fore people of New Guinea and it was described at year of 1957 (3). Kuru was a progressive cerebellar ataxia leaving victims helpless within a few months; cognitive changes developed only in advanced stages of disease (4). However, in acquired classes of TSEs disease were been reported spreading among the healthy person by transplantation of infected corneas, use of purified hormones or transfusion with contaminated blood of Creutzfeldt-Jakob disease. In year 2008, 10 cases of Bovine Spongiform Encephalopathy (BSE or Mad Cow Disease) were been reported among the cattle in Britain (5). This was occurs because of their breeder practices by feeeding the cattle with protein supplement. For familial TSEs disease classes, there were associated to autosomal dominant mutation in the prnp gene. Such example for this classes are Creutzfeldt-Jakob disease and Fatal Familial Insomnia. Over 50 different mutations of PRNP have been found in familial CJD, which four point mutations at the codons 102, 178, 200, and 210 and insertions of five or six octapeptide repeats account for 95% of the familial cases (6). While, for fatal familial insomnia, the mutation of PRNP at the codon 178 (7).

REFERENCES 1. Will RG, Mathews WB. A retrospective study of Creutzfeldt-Jakob

disease in England and Wales 1970–79,: clinical features. J Neurol Neurosurg Psychiatry 1984; 47: 134–40. 2. Bernoulli CC, Masters CL, Gajdusek DC, Gibbs CJ Jr, Harris JO. Early clinical features of Creutzfeldt-Jakob disease (subacute spongiform encephalopathy) In: Prusiner SB, Hadlow WJ, eds. Slow transmissible diseases of the nervous system, vol 1: clinical, epidemiological,

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genetic and pathological aspects of the spongiform encephalopathies. New York: Academic Press, 1979: 229–41. Gajdusek DC, Zigas V. Degenerative disease of the nervous system in New Guinea: the endemic occurrence of “kuru” in the native population. N Engl J Med 1957; 257: 974–78. Hornabrook RW. Kuru—a subacute cerebellar degeneration: the natural history and clinical features. Brain 1968; 91: 53–74. Number of cases of bovine spongiform encephalopathy (BSE) reported in the United Kingdom. Websites : http://www.oie.int/eng/info/en_esbru.htm#1 Capellari S, Cardone F, Notari S, et al. Creutzfeldt-Jakob disease associated with the R208H mutation in the prion protein gene, Neurology 2005; 64: 905–07.. Medori R, Tritschler HJ, LeBlanc A, et al. Fatal familial insomnia: a prion disease with a mutation at codon 178 of the prion protein gene. N Engl J Med 1992; 326: 444–49.

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