Browsing by Author "Assis, Girley Francisco Machado de"

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    Avaliação do programa de controle da doença de Chagas no município de Berilo, Vale do Jequitinhonha, MG, Brasil, oito anos após a implantação da vigilância epidemiológica.
    (Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa e Pós Graduação, Universidade Federal de Ouro Preto., 2006) Assis, Girley Francisco Machado de; Lana, Marta de
    Neste trabalho foi realizada uma Pesquisa Integral (PI) Triatomínica no município de Berilo, Vale do Jequitinhonha, MG, Brasil, onde todas as unidades domiciliares rurais e urbanas foram vistoriadas com o objetivo de avaliar o impacto do Programa de Controle de Doença de Chagas, implantado no município desde 1982, sobre as populações de triatomíneos domiciliadas e peridomiciliadas. Os insetos capturados foram identificados e examinados quanto à infecção pelo T. cruzi. Todas as UD’s que apresentaram triatomíneos no intra ou peridomicílio foram borrifadas utilizando inseticida piretróide. Realizou-se também um inquérito sorológico em moradores residentes em UD’s infestadas por triatomíneos. A coleta de sangue foi feita por punção venosa e examinado por HAI, ELISA e IFI. Durante os trabalhos da PI, 5.242 UD’s foram vistoriadas e 35 apresentaram-se infestadas. Os triatomíneos encontrados foram P. megistus (72%) e T. pseudomaculata (28%), sendo o peridomicílio (galinheiro) o principal local das capturas. Dos 391 insetos capturados nenhum apresentou infecção pelo T. cruzi. Pela primeira vez em Minas Gerais foi encontrado um grande foco intradomiciliar de T. pseudomaculata. Considerando o padrão de construção das moradias do município, a maioria da UD’s pertencia ao tipo A (49%) e C (40%). Dentre as UD’s positivas, 74% era do tipo C. As capturas se concentraram na região Norte do município e ocorreu sobreposição da área de P. megistus e T. pseudomaculata. A prevalência humana para a infecção pelo T. cruzi foi de 25% (31 indivíduos), sendo 97% dos indivíduos maiores de 30 anos. A quase ausência de infecção em crianças, associada aos dados entomológicos da PI nos permite concluir que a transmissão vetorial da DCh está interrompida em Berilo. Comparando os dados da PI e os da Vigilância Epidemiológica (VE), implantada desde 1997, verifica-se que Berilo vem apresentando indicadores entomológicos condizentes com a VE. Vale ressaltar que esta VE apresenta falhas metodológicas que são frutos de um processo de descentralização implantado de forma precipitada, já que o município não foi preparado e/ou capacitado para assumir as suas devidas obrigações.
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    Avaliação laboratorial e clínica de indivíduos chagásicos tratados com benzonidazol e não tratados residentes no município de Berilo, Vale do Jequitinhonha, MG.
    (Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa e Pós Graduação, Universidade Federal de Ouro Preto., 2011) Assis, Girley Francisco Machado de; Lana, Marta de
    Um dos maiores desafios na doença de Chagas é avaliar o impacto do tratamento etiológico nos parâmetros clínicos e laboratoriais dos pacientes tratados. Sendo assim, o objetivo deste trabalho foi avaliar a efetividade do benzonidazol na evolução clínica dos pacientes chagásicos tratados e não tratados, residentes no município de Berilo, Vale do Jequitinhonha, MG. A primeira parte deste trabalho teve como propósito avaliar 94 pacientes chagásicos tratados há mais de 10 anos, utilizando sorologia convencional (ELISA, IFI e HAI), sorologia alternativa (rec-ELISA e FC-ALTA) e métodos parasitológicos (HC e PCR). A sorologia convencional permitiu categorizar os pacientes em três grupos: tratados não curados (TNC), tratados em avaliação (TEA) e tratados curados (TC), segundo o critério clássico de cura (negativação de dois testes sorológicos negativos) ou critério mais rigoroso (negativação de três testes sorológicos negativos). O critério clássico revelou 78,7% dos pacientes TNC, 8,5% TEA e 12,8% TC. Já o critério mais rigoroso revelou 63,8% dos pacientes TNC, 28,7% TEA e 7,4% TC. As associações de dois testes da sorologia convencional (ELISA+IFI, ELISA+HAI e IFI+HAI) foram avaliadas e demonstraram resultados semelhantes entre associações de ELISA+IFI e IFI+HAI com o critério mais rigoroso. A rec-ELISA e a FC-ALTA apresentaram resultados mais consistentes com o critério de cura mais rigoroso, mas cada teste revelou isoladamente um paciente negativo não revelado pela sorologia convencional. A HC revelou falha terapêutica em 17% (16/94) dos pacientes, todos categorizados como TNC por ambos os critérios. A PCR apresentou resultados negativos consistentes com os demais métodos sorológicos e parasitológicos empregados como critério de cura. A avaliação clínica revelou no grupo TC maior percentual de forma indeterminada, ausência de forma digestiva e menor percentual de forma cardíaca. A segunda parte deste trabalho avaliou comparativamente os resultados da efetividade terapêutica e evolução clínica de 29 dos 94 pacientes tratados na fase crônica da infecção, utilizando o critério de cura atual. Não foi observada cura parasitológica e nem mesmo queda sorológica em nenhum paciente em todos os períodos pós-tratamento. A HC revelou falha terapêutica em 10,3% (3/29) dos pacientes e a PCR apresentou um percentual de positividade de 58,6% (17/29). A avaliação clínica destes pacientes, treze anos pós-tratamento, revelou uma evolução progressiva em 27,6% (8/29) dos pacientes. O índice de evolução clínica dos pacientes tratados na forma indeterminada foi quatro vezes menor se comparado com aqueles que apresentavam alguma alteração cardíaca ou digestiva antes do tratamento. Na terceira parte deste trabalho foram avaliados os aspectos laboratoriais e clínicos de 58 pacientes chagásicos dos quais 29 foram tratados com benzonidazol há 13 anos e 29 não tratados. A HC apresentou maior percentual de positividade entre os não tratados quando comparados com os tratados (27,6% x 6,9%). Foi observada uma queda sorológica significativa no grupo tratado quando comparado com o não tratado, sendo esta mais elevada nos pacientes tratados na forma indeterminada. Os pacientes tratados apresentaram menor percentual de evolução clínica quando comparados com os não tratados (27,6% x 65,5%) e os tratados na forma indeterminada apresentaram menor índice de evolução quando comparados com os não tratados (1,3% x 4.3%). Em conjunto, estes resultados revelam um baixo percentual de cura parasitológica em pacientes chagásicos tratados na fase crônica da infecção, mas um melhor prognóstico da doença foi observado em pacientes tratados na forma indeterminada quando comparados com o grupo não tratados.
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    Clinical and laboratory status of patients with chronic Chagas disease living in a vector controlled area in Minas Gerais, Brazil, before and nine years after aetiological treatment.
    (2009) Lana, Marta de; Lopes, Leonardo de Araújo; Martins, Helen Rodrigues; Bahia, Maria Terezinha; Assis, Girley Francisco Machado de; Wendling, Ana Paula Barbosa; Martins Filho, Olindo Assis; Montoya, Roberto Araújo; Dias, João Carlos Pinto; Viñas, Pedro Albajar; Coura, José Rodrigues
    Twenty-eight Chagas disease patients (CD), 22 with the indeterminate clinical form (IND) and six with the cardiac or digestive form (CARD/DIG), were treated with benznidazole and underwent clinical and laboratorial analysis before (IND and CARD/DIG) and nine years after [patients after treatment (CDt), patients with the indeterminate clinical form at treatment onset (INDt) and with the cardiac or digestive form at treatment onset (CARD/DIGt)] treatment. The data demonstrate that 82.1% of CDt patients (23/28) remained clinically stable and 95.4% of the INDt (21/22) and 33.3% of the CARD/DIGt (2/6) patients showed unaltered physical and laboratorial examinations. The clinical evolution rate was 2%/year and was especially low in INDt patients (0.5%/year) relative to CARD/DIGt patients (7.4%/year). Positive haemoculture in treated patients was observed in 7.1% of the cases. None of the INDt (0/21) and 33.3% of the CARD/DIGt (2/6) patients displayed positive cultures. The PCR presented a positive rate significantly higher (85.2%, 23/27) than haemoculture and two samples from the same patient revealed the same result 57.7% of the patients. Conventional serology-ELISA on 16 paired samples remained positive in all individuals. Semi-quantitative ELISA highlighted significant decreases in reactivity, particularly in INDt relative to IND. Non-conventional serology- FC-ALTA-IgG, after treatment, showed positive results in all sera and 22 paired samples examined at seven and nine years after treatment, demonstrated significantly lower reactivity, particularly in INDt patients. This study was retrospective in nature, had a low number of samples and lacked an intrinsic control group, but the data corroborate other results found in the literature. The data also demonstrate that, even though a cure has not been detected in the none-treated patients, the benefits for clinical evolution were selectively observed in the group of INDt patients and did not occur for CARD/DIGt patients.
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    Course of serological tests in treated subjects with chronic Trypanosoma cruzi infection : a systematic review and meta-analysis of individual participant data.
    (2018) Sguassero, Yanina; Roberts, Karen N.; Harvey, Guillermina B.; Comandé, Daniel; Cuesta, Cristina B.; Aguiar, Camila; Castro, Ana M. de; Danesi, Emmaría; Andrade, Ana L. de; Lana, Marta de; Escribà, Josep M.; Fabbro, Diana L.; Fernandes, Cloé Duarte; Flores Chávez, María; Hasslocher Moreno, Alejandro Marcel; Jackson, Yves Laurent; Assis, Girley Francisco Machado de; Maldonado, Marisel; Meira, Wendell Sérgio Ferreira; Molina, Israel; Monje Rumi, María Mercedes; Martín, Catalina Muñoz-San; Murcia, Laura; Castro, Cleudson Nery de; Negrette, Olga Sánchez; Segovia, Manuel; Silveira, Celeste Aída Nogueira; Solari, Aldo; Steindel, Mário; Streiger, Mirtha Leonor; Bilbao, Ninfa Vera de; Zulantay, Inés; Sosa Estani, Sergio
    Objective To determine the course of serological tests in subjects with chronic Trypanosoma cruzi infection treated with anti-trypanosomal drugs. Methods A systematic review and meta-analysis was conducted using individual participant data. Survival analysis and the Cox proportional hazards regression model with random effects to adjust for covariates were applied. The protocol was registered in the PROSPERO database (http://www.crd.york.ac.uk/PROSPERO; CRD42012002162). Results A total of 27 studies (1296 subjects) conducted in eight countries were included. The risk of bias was low for all domains in 17 studies (63.0%). Nine hundred and thirteen subjects were assessed (149 seroreversion events, 83.7% censored data) for enzyme-linked immunosorbent assay (ELISA), 670 subjects (134 events, 80.0% censored) for indirect immunofluorescence assay (IIF), and 548 subjects (99 events, 82.0% censored) for indirect hemagglutination assay (IHA). A higher probability of seroreversion was observed within a shorter time span in subjects aged 1–19 years compared to adults. The chance of seroreversion also varied according to the country where the infection might have been acquired. For instance, the pooled adjusted hazard ratio between children/adolescents and adults for the IIF test was 1.54 (95% confidence interval 0.64–3.71) for certain countries of South America (Argentina, Bolivia, Chile, and Paraguay) and 9.37 (95% confidence interval 3.44–25.50) for Brazil. Conclusions The disappearance of anti-T. cruzi antibodies was demonstrated along the course of follow-up. An interaction between age at treatment and country setting was found.
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    Domiciliation of Triatoma pseudomaculata (Corrêa e Espínola 1964) in the Jequitinhonha Valley, State of Minas Gerais.
    (2007) Assis, Girley Francisco Machado de; Azeredo, Bernardino Vaz de Mello; Fuente, Ana Laura Carbajal de la; Diotaiuti, Liléia Gonçalves; Lana, Marta de
    Oito anos após a implantação da vigilância epidemiológica para doença de Chagas em Berilo, Vale do Jequitinhonha, MG, Brasil, foi realizada uma pesquisa para verificar o impacto do Programa de Controle Vetorial. Neste trabalho, 5.242 (96%) unidades domiciliares foram vistoriadas. Dez estavam infestadas por Triatoma pseudomaculata. Em nove delas os insetos estavam infestando o peridomicílio e em uma casa foi constatado um foco intradomiciliar associado a morcegos. Foram capturados 111 insetos da espécie Triatoma pseudomaculata e nenhum exemplar estava infectado por Trypanosoma cruzi. Na casa infestada e em torno dela foram instaladas respectivamente 8 e 100 armadilhas de Noireau et al16 e nenhum triatomíneo foi capturado. Oitenta morcegos capturados e examinados também estavam negativos para Trypanosoma cruzi bem como três gambás (Didelphis albiventris) e um roedor, todos capturados no peridomicílio. Um porcentual de 24% dos moradores das casas infestadas por Triatoma pseudomaculata foi sororeativo (ELISA, HAI e IFI) para Tripanosoma cruzi.
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    Entomological surveillance of Chagas disease in Berilo municipality, Jequitinhonha Valley, State of Minas Gerais, Brazil.
    (2009) Assis, Girley Francisco Machado de; Azeredo, Bernardino Vaz de Mello; Gorla, David; Diotaiuti, Liléia Gonçalves; Lana, Marta de
    O objetivo deste estudo foi avaliar o Programa de Controle de doença de Chagas instalado desde 1982 no município de Berilo, Vale do Jequitinhonha, MG, Brasil, baseado na avaliação de 5.242 unidades domiciliares e 7.807 anexos após oito anos de implantação da vigilância epidemiológica que ocorreu em 1997. Um total de 391 triatomíneos (280 Panstrongylus megistus e 111 Triatoma pseudomaculata) foram capturados, indicando o contínuo predomínio da primeira espécie. No entanto, Triatoma pseudomaculata está claramente se tornando mais importante nesta região, com colônias intradomiciliares sendo detectadas recentemente. Parâmetros entomológicos, como os índices de dispersão (17%) e infestação intradomiciliar (0,15%), são compatíveis com a fase de vigilância epidemiológica. A maioria das UDs apresenta padrão de construção tipo A (tijolo com reboco) e A maioria das UDs apresenta padrão de construção tipo A (tijolo com reboco) e C (adobe com reboco). Dentre os habitantes das unidades domiciliares infestadas por triatomíneos, 25% apresentavam testes reativos na ELISA, HAI e IFI para antígenos de Trypanosoma cruzi.
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    Evaluation of the Chagas disease control program in Açucena Municipality, Rio Doce Valley, State of Minas Gerais, Brazil.
    (2014) Santos, Adriana dos; Letro, Rejane Balmant; Bem, Vitor Antônio Lemos do; Azeredo, Bernardino Vaz de Mello; Coelho, George Luiz Lins Machado; Diotaiuti, Liléia Gonçalves; Assis, Girley Francisco Machado de; Lana, Marta de
    Açucena Municipality, Rio Doce Valley, State of Minas Gerais, Brazil temporarily (2001-2005) interrupted epidemiological surveillance for Chagas disease. The objective of this work was to evaluate the Chagas Disease Control Program (CDCP) in Açucena and to offer suggestions for improving local epidemiological surveillance. Methods: This study was conducted in three phases: I) a serological investigation of schoolchildren aged 5 to 15 years using an enzyme-linked immunosorbent assay (ELISA) test performed on blood collected on fi lter paper followed by ELISA, indirect immunofl uorescence (IIF) and indirect hemaglutination (IHA) on venous blood for borderline cases and those in the gray zone of reactivity; II) vector evaluation using the data obtained by local health agents during 2006-2010; and III) examination by ELISA, IIF and IHA of serum samples from the inhabitants of houses where infected Triatoma vitticeps was found and evaluation of their knowledge about Chagas disease. Results: Five individuals had inconclusive results in the ELISA screening but were seronegative for Chagas disease. The triatomine evaluation revealed the presence of three species: Triatoma vitticeps, Panstrongylus megistus and Panstrongylus diasi. Triatoma vitticeps was the most prevalent and widespread, with a higher (67%) index of Trypanosoma cruzi fl agellates and evidence of colonization. Most of the inhabitants of the infested houses recognized triatomines and had basic knowledge about Chagas disease. Conclusions: Although T. vitticeps is not clearly associated with Chagas disease transmission, these results highlight the importance of maintaining CDCP in endemic areas and the need for greater emphasis on epidemiological surveillance, especially in areas with important vectorial changes or that have been modifi ed by human intervention.
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    Experimental benznidazole treatment of Trypanosoma cruzi II strains isolated from children of the Jequitinhonha Valley, Minas Gerais, Brazil, with Chagas disease.
    (2015) Silva, Jaquelline Carla Valamiel de Oliveira e; Assis, Girley Francisco Machado de; Oliveira, Maykon Tavares de; Paiva, Nívia Carolina Nogueira de; Araújo, Márcio Sobreira Silva; Carneiro, Cláudia Martins; Martins Filho, Olindo Assis; Martins, Helen Rodrigues; Lana, Marta de
    Trypanosoma cruzi strains from distinct geographic areas show differences in drug resistance and association between parasites genetic and treatment response has been observed. Considering that benznidazole (BZ) can reduce the parasite burden and tissues damage, even in not cured animals and individuals, the goal is to assess the drug response to BZ of T. cruzi II strains isolated from children of the Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected and treated with BZ in both phases of infection were compared with the untreated and evaluated by fresh blood examination, haemoculture, polymerase chain reaction, conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in the acute phase, a significant decrease in parasitaemia was observed for all strains. Positive parasitological and/or serological tests in animals treated during the acute and chronic (95.1-100%) phases showed that most of the strains were BZ resistant. However, beneficial effect was demonstrated because significant reduction (p < 0.05%) and/or suppression of parasitaemia was observed in mice infected with all strains (acute phase), associated to reduction/elimination of inflammation and fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals, what suggest that BZ use may be recommended at least for recent chronic infection of the studied region.
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    In-house ELISA method to analyze anti-Trypanosoma cruzi IgG reactivity for differential diagnosis and evaluation of Chagas disease morbidity.
    (2012) Santos, Lilian da Silva; Torres, Rosália Morais; Assis, Girley Francisco Machado de; Bahia, Maria Terezinha; Martins, Helen Rodrigues; Carvalho, Andréa Teixeira de; Reis, Jordana Grazziela Alves Coelho dos; Viñas, Pedro Albajar; Martins Filho, Olindo Assis; Lana, Marta de
    O objetivo foi desenvolver um método sorológico in-house de alta especificidade e sensibilidade para diagnosticar e monitorar a morbidade da doença de Chagas. Métodos: Para tal, a reatividade sorológica de IgG e subclasses foi testada em soros de pacientes chagásicos de Berilo, Vale do Jequitinhonha/MG/Brasil. A reatividade sorológica foi também avaliada em amostras de pacientes com outras doenças infecto-contagiosas relevantes, incluindo o HIV, vírus da hepatite C (VHC), sífilis (SYP), leishmaniose visceral (LV), leishmaniose tegumentar americana (LTA) e controles não infectados (NI) para verificar o desempenho do método. Outras análises foram feitas para avaliar a aplicabilidade desta metodologia no monitoramento da morbidade da doença de Chagas. Com este propósito os pacientes com doença de Chagas foram anteriormente classificados em três grupos: indeterminados (IND), cardíacos (CARD) e digestivos/mistos (DIG/Mis) conforme seu estado clínico. Resultados: A análise da reatividade sorológica de IgG total na diluição 1:40 mostrou ser uma abordagem importante no diagnóstico da doença de Chagas (100% de sensibilidade e especificidade e ausência de reação cruzada com as demais infecções). A análise das subclasses de IgG mostrou reação cruzada principalmente com NI, LV e LTA em todas as diluições. O grupo IND apresentou a maior reatividade para IgG3 e o grupo DIG/Mis apresentou nível mais elevado de IgG se comparados aos grupos IND e CARD. Conclusões: Estes achados demonstram que o método de ELISA in-house apresenta uma promissora aplicabilidade no diagnóstico diferencial e na avaliação da morbidade da doença de Chagas.
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    Innovations in diagnosis and post-therapeutic monitoring of Chagas disease : simultaneous flow cytometric detection of IgG1 antibodies anti-live amastigote, anti-live trypomastigote, and anti-fixed epimastigote forms of Trypanosoma cruzi.
    (2014) Alessio, Glaucia Diniz; Côrtes, Denise Fonseca; Assis, Girley Francisco Machado de; Sales Júnior, Policarpo Ademar; Ferro, Eloisa Amália Vieira; Antonelli, Lis Ribeiro do Valle; Carvalho, Andréa Teixeira de; Martins Filho, Olindo Assis; Lana, Marta de
    This study developed a remarkable methodological innovation (FC-ATE) which enables simultaneous detection of antibodies specific to the three evolutive forms of Trypanosoma cruzi: live amastigote (AMA), live trypomastigote (TRYPO), and fixed epimastigote (EPI) using a differential fluorescence staining as low (AMA), intermediate (TRYPO), and high (EPI). An outstanding performance (100%) was observed in the discrimination of the chagasic (CH) and non-chagasic (NCH) patients. In the applicability of FC-ATE in the diagnosis of Chagas disease, 100% of the CH samples presented positivity in the percentage of positive fluorescent parasites (PPFP) for all the three forms of T. cruzi. Moreover, 94% of the samples of NCH presented negative values of PPFP with AMA and TRYPO, and 88% with EPI. Samples from the NCH group with falsepositive results were those belonging to the leishmaniasis patients. Considering the applicability of this technique in post-therapeuticmonitoring of Chagas disease, 100% of non-treated (NT) and treated non-cured (TNC) samples were positive with the three T. cruzi evolutive forms, while a percentage of 100% fromsamples of the treated cured (TC) patientswere negativewith AMA, 93% with TRYPO and 96% with EPI. The comparison between FC-ATE and two other flow cytometric tests using the same samples of patients NT, TNC and TC showed that the three techniques presented different reactivities, although categorical correlation between the methodologies was observed. Taken together, the results obtained with the novel FC-ATE method have shown an outstanding performance in the diagnosis and post-therapeutic monitoring of Chagas disease.
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    Molecular and biological characterization of Trypanosoma cruzi strains isolated from children from Jequitinhonha Valley, State of Minas Gerais, Brazil.
    (2013) Silva, Jaquelline Carla Valamiel de Oliveira e; Assis, Girley Francisco Machado de; Oliveira, Maykon Tavares de; Valadares, Helder Magno Silva; Valle, Ítalo Faria do; Paiva, Nívia Carolina Nogueira de; Martins, Helen Rodrigues; Lana, Marta de
    The biological diversity of Trypanosoma cruzi strains plays an important role in the clinical and epidemiological features of Chagas disease. Methods: Eight T. cruzi strains isolated from children living in a Chagas disease vector-controlled area of Jequitinhonha Valley, State of Minas Gerais, Brazil, were genetically and biologically characterized. Results: The characterizations demonstrated that all of the strains belonged to T. cruzi II, and showed high infectivity and a variable mean maximum peak of parasitemia. Six strains displayed low parasitemia, and two displayed moderate parasitemia. Later peaks of parasitemia and a predominance of intermediate and large trypomastigotes in all T. cruzi strains were observed. The mean prepatent period was relatively short (4.2±0.25 to 13.7±3.08 days), whereas the patent period ranged from 3.3±1.08 to 34.5±3.52 days. Mortality was observed only in animals infected with strain 806 (62.5%). Histopathological analysis of the heart showed that strains 501 and 806 caused infl ammation, but fi brosis was observed only in animals infected with strain 806. Conclusions: The results indicate the presence of an association between the biological behavior in mice and the genetic characteristics of the parasites. The study also confi rmed general data from Brazil where T. cruzi II lineage is the most prevalent in the domiciliary cycle and generally has low virulence, with some strains capable of inducing infl ammatory processes and fi brosis.
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    Posttherapeutic cure criteria in Chagas disease : conventional serology followed by supplementary serological, parasitological, and molecular tests.
    (2012) Assis, Girley Francisco Machado de; Silva, Alexandre Rotondo da; Bem, Vitor Antônio Lemos do; Bahia, Maria Terezinha; Martins Filho, Olindo Assis; Dias, João Carlos Pinto; Viñas, Pedro Albajar; Torres, Rosália Morais; Lana, Marta de
    We performed a critical study of conventional serology, followed by supplementary serological, parasitological, and molecular tests, to assess the response to etiologic treatment of Chagas’ disease. A group of 94 Chagas’ disease patients treated with benznidazole at least 10 years earlier were evaluated from the laboratory and clinical points of view. When conventional serology (enzyme- linked immunosorbent assay [ELISA], indirect immunofluorescence [IIF], and indirect hemagglutination [IHA]) and classic criteria (consistent results with any two of the three tests) or more rigorous criteria (consistent results from the three tests) were used, 10.6% and 8.5% of patients were considered treated and cured (TC) by classic and rigorous criteria, respectively. Patients were then evaluated using supplementary (recombinant ELISA and Trypanosoma cruzi excreted-secreted antigen blotting [TESA-blot]), parasitological (hemoculture), and molecular (PCR) tests. The results of recombinant ELISA were similar to those with the rigorous criterion (three consistent test results). The TESA-blot group showed a higher percentage (21.3%) of negative results than the groups defined by either cure criterion. Hemoculture and PCR gave negative results for all treated and cured (TC) patients, regardless of the criterion used. Recombinant ELISA and TESA-blot tests showed negative results for 70% and 87.5% of the patients categorized as TC by the classic and three-test criteria, respectively. For patients with discordant conventional serology, the supplementary serological and molecular tests were the decisive factor in determining therapeutic failure. Clinical evaluation showed that 62.5% of TC patients presented with the indeterminate form of the disease. Additionally, treated patients with negative TESA-blot results should be reevaluated later with all methodologies used here to verify whether TESAblot is a reliable way to determine early parasitological cure of Chagas’ disease.
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    A serological, parasitological and clinical evaluation of untreated Chagas disease patients and those treated with benznidazole before and thirteen years after intervention.
    (2013) Assis, Girley Francisco Machado de; Diniz, Glaucia Alessio; Montoya, Roberto Araújo; Dias, João Carlos Pinto; Coura, José Rodrigues; Coelho, George Luiz Lins Machado; Viñas, Pedro Albajar; Torres, Rosália Morais; Lana, Marta de
    The etiological treatment of Chagas disease is recommended for all patients with acute or recent chronic infection, but controversies remain regarding the benefit of chemotherapy and interpretations of the parasitological cure after etiological treatment. This study compares the laboratory and clinical evaluations of Chagas disease patients who were diagnosed 13 years earlier. Fifty-eight Chagas disease patients (29 treated with benznidazole and 29 untreated) were matched at the time of treatment based on several variables. Conventional serology revealed the absence of seroconversion in all patients. However, lower serological titres were verified in the treated group, pri¬marily among patients who had the indeterminate form of the disease. Haemoculture performed 13 years after the intervention was positive for 6.9% and 27.6% of the treated and untreated patients, respectively. Polymerase chain reaction tests were positive for 44.8% and 13.8% of the treated and untreated patients, respectively. Patients who presented with the indeterminate form of the disease at the beginning of the study exhibited less clinical progression (17.4%) compared with the untreated group (56.5%). Therefore, this global analysis revealed that etiological treatment with benznidazole may benefit patients with respect to the clinical progression of Chagas disease and the prognosis, particularly when administered to patients with the indeterminate form of the disease.
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    Seroprevalence of chagas disease in schoolchildren from two municipalities of jequitinhonha valley, Minas Gerais, Brazil; six years following the onset of epidemiological surveillance.
    (2006) Borges, Jaila Dias; Assis, Girley Francisco Machado de; Gomes, Lizziani de Vasconcelos; Dias, João Carlos Pinto; Pinto, Ildikô Delkim Miranda; Martins Filho, Olindo Assis; Torres, Rosália Morais; Viñas, Pedro Albajar; Bahia, Maria Terezinha; Coelho, George Luiz Lins Machado; Lana, Marta de
    Six years after the beginning of the epidemiological surveillance of Chagas disease in Berilo and José Gonçalves de Minas, Jequitinhonha Valley, MG, Brazil, a serological inquiry was performed to observe whether the transmission of this endemy was occurring in this area. A randomized sample of 1,412 children seven to 14 years old, was screened. Six asymptomatic children were found to be positive, leading to 0.4% of prevalence. Hemoculture confirmed infection in five out of the six positive cases. Additional epidemiological investigation revealed important antecedents, such as disease reports in relatives and predisposing ecological and housing conditions. Our results demonstrated similar seroprevalence (0.4%) in schoolchildren, ranging from seven to 14 years old, and that were observed six years ago (0.2%) for children 0-9 year-old. Thus, considering the constant presence of Panstrogylus megistus in the peridomicile these findings emphasize the need of continuous improved epidemiological surveillance of Chagas disease in this region.
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    Trypanosoma cruzi Discret Typing Units (TcII and TcVI) in samples of patients from two municipalities of the Jequitinhonha Valley, MG, Brazil, using two molecular typing strategies.
    (2015) Oliveira, Maykon Tavares de; Assis, Girley Francisco Machado de; Silva, Jaquelline Carla Valamiel de Oliveira e; Machado, Evandro Marques de Menezes; Silva, Glenda Nicioli da; Veloso, Vanja Maria; Macedo, Andréa Mara; Martins, Helen Rodrigues; Lana, Marta de
    Background: Trypanosoma cruzi is classified into six discrete taxonomic units (DTUs). For this classification, different biological markers and classification criteria have been used. The objective was to identify the genetic profile of T. cruzi samples isolated from patients of two municipalities of Jequitinhonha Valley, MG, Brazil. Methods: Molecular characterization was performed using two different criteria for T. cruzi typing to characterize 63 T. cruzi samples isolated from chronic Chagas disease patients. The characterizations followed two distinct methodologies. Additionally, the RAPD technique was used to evaluate the existence of genetic intragroup variability. Results: The first methodology identified 89 % of the samples as TcII, but it was not possible to define the genetic identity of seven isolates. The results obtained with the second methodology corroborated the classification as TcII of the same samples and defined the classification of the other seven as TcVI. RAPD analysis showed lower intra-group variability in TcII. Conclusions: The results confirmed the preliminary data obtained in other municipalities of the Jequitinhonha Valley, showing a predominance of TcII, similar to that verified in northeast/south axis of Brazil and the first detection of TcVI in the study region. The second protocol was more simple and reliable to identify samples of hybrid character.