Prion diseases are under compulsory notification in Brazil: Surveillance of cases evaluated by biochemical and/or genetic markers from 2005 to 2007

Abstract

The emergence of the new variant of Creutzfeldt-Jakob disease (vCJD) in the United Kingdom has raised concerns over the risks of this prion disease in other parts of the world. Since 2005, human prion diseases have been under compulsory notification in Brazil. It is well known that some polymorphisms within the cellular prion gene (PRNP) have been associated to a higher susceptibility to sporadic CJD (sCJD) and vCJD.ObjectivesTo describe the first notified cases and to evaluate the presence of mutations and polymorphisms of the PRNP in these cases.MethodsThirty-five notified cases were evaluated by clinical, auxiliary exams and biochemical and/or genetic tests and classified according to the World Health Organization criteria for CJD. A control group (N=202) was included for the purpose of comparing the genetic analyses.ResultsTwenty seven cases (74%) were classified as possible sCJD while 51% fulfilled the criteria for probable sCJD. Brain tissue analysis was available in three cases, where two were classified as definite sCJD and one as unconfirmed sCJD. Mutation of the PRNP was not found, and regarding the codon 129 polymorphism, valine in both alleles (Val129Val) was more frequent in patients than in the control group (OR=4.98; 1.55-15.96; p=0.007) when all possible cases were included, but not when only probable cases were considered.ConclusionsOur data did not show correlation of PRNP polymorphisms with probable sCJD cases. It is necessary to work toward notification of all cases of possible CJD in Brazil and to increase the rate of definitive diagnoses.

First case of V180I rare mutation in a Brazilian patient with Creutzfeldt-Jakob disease

“…4 Homozygous for methionine at codon 129 (M129M) is a well-established risk factor for sCJD, 7 although this association has not been shown in any previous study using a Brazilian sCJD cohort. 8 Our patient presented the haplotype V180I/129M, and once the polymorphism at the codon 129 has a modifying effect on the phenotype and interferes with the susceptibility to all prion diseases, 9 this may explain the overlapping of symptoms between gCJD and sCJD presented in this patient.…”

Avaliação epidemiológica dos óbitos por doenças priônicas no Brasil sob o enfoque da biossegurança

“…Contudo, na presença de um conjunto de características próprias da doença, a identificação de 14-3-3 no líquor tem um alto grau de especificidade e sensibilidade para o diagnóstico das formas de DCJ. Porém, o diagnóstico definitivo só é alcançado por intermédio do exame neuropatológico confirmatório, no qual há a necessidade de obtenção do tecido cerebral do paciente, obtido após a morte por meio de necropsia, para estudo histopatológico, imunohistoquímico e/ou aplicação de outras técnicas especializadas como Western blot, Elisa e PCR, que permitem demonstrar a presença da proteína priônica patógena 2,10, [16][17][18][19][20][21][22][23][24][25][26][27][28][29] .…”

Hashimoto's encephalopathy with clinical features similar to those of Creutzfeldt-Jakob disease

“…A recent study by Martins et al described the first 35 cases of Creutzfeldt-Jakob disease notified in Brazil, 26 of these cases were initially classified as possible sCJD, of which 51% fulfilled the criteria for probable sCJD. The most frequent clinical manifestations were myoclonus (80%), pyramidal signs (68%), ataxia (65%) and early psychiatric symptoms (55%) 10 .…”