II Consenso Brasileiro em Doença de Chagas, 2015 / Brazilian Consensus on Chagas Disease, 2015

A doença de Chagas é uma condição crônica negligenciada com elevada carga de morbimortalidade e impacto dos pontos de vista psicológico, social e econômico. Representa um importante problema de saúde pública no Brasil, com diferentes cenários regionais. Este documento traduz a sistematização das evidências que compõe o Consenso Brasileiro de Doença de Chagas. O objetivo foi sistematizar estratégias de diagnóstico, tratamento, prevenção e controle da doença de Chagas no país, de modo a refletir as evidências científicas disponíveis. Sua construção fundamentou-se na articulação e contribuição estratégica de especialistas brasileiros com conhecimento, experiência e atualização sobre diferentes aspectos da doença. Representa o resultado da estreita colaboração entre a Sociedade Brasileira de Medicina Tropical e o Ministério da Saúde. Espera-se com este documento fortalecer o desenvolvimento de ações integradas para enfrentamento da doença no país com foco em epidemiologia, gestão, atenção integral (incluindo famílias e comunidades), comunicação, informação, educação e pesquisas.

Chagas disease is a neglected chronic condition that presents high morbidity and mortality burden, with considerable psychological, social, and economic impact. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on collaboration and contribution of renowned Brazilian experts with vast knowledge and experience on various aspects of the disease. It is the result of close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. This document shall strengthen the development of integrated control measures against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research.

Diagnosis of Chagas disease: what has been achieved? What remains to be done with regard to diagnosis and follow up studies?

In the acute phase and in the chronic forms of Chagas disease, the etiological diagnosis may be performed by detection of the parasite using direct or indirect parasitological methods and by the presence of antibodies in the serum by way of serological tests. Several techniques are easily available, ranging from the simplest wet smear preparation to immuno-enzymatic assays with recombinant antigens that will meet most diagnostic needs. Other tests under evaluation include a molecular test using polymerase chain reaction, which has shown promising results and may be used as a confirmatory test both in the acute and chronic phases of the disease. Better rapid tests are needed for diagnosis, some of which are already under evaluation. Additionally, there is a need for tools that can identify patients cured shortly after specific treatment. Other needs include a marker for prognosis and early diagnosis of congenital transmission.

Busca retrospectiva da transmissão maternal da infecção chagásica em pacientes na fase crônica / A retrospective search for maternal transmission of Chagas infection from patients in the chronic phase

Avaliamos a transmissão maternal do Trypanosoma cruzi em 278 filhos de 145 mães com a doença crônica causada por esse protozoário, nascidos após o estabelecimento do diagnóstico materno. Usamos, nas mães e nos filhos, provas sorológicas como base do objetivo do estudo. Verificamos que ocorreram apenas duas veiculações pela modalidade citada (2/278 = 0,7 por cento). Como houve amamentação, não foi possível diferenciar, nesses casos, a transmissão congênita da adquirida pelo leite, mas, de qualquer forma, processou-se transmissão maternal, que constitui uma das modalidades alternativas de infecção pelo Trypanosoma cruzi. A metodologia empregada é mais uma dentre as diversas propostas para aquilatar a prevalência desse tipo de propagação do Trypanosoma cruzi. Ao lado da constatação fundamental, registramos fatos relacionados com a gestação, parto, puerpério, abortamento, prematuridade, nati-neomortalidade e aleitamento materno, que podem representar subsídios para melhores interpretações sobre o assunto.

Parasite persistence in treated chagasic patients revealed by xenodiagnosis and polymerase chain reaction

Polymerase chain reaction (PCR) was compared with xenodiagnosis performed 20 years after trypanocidal chemotherapy to investigate parasite clearance. Eighty-five seropositive individuals for Chagas disease presenting a positive xenodiagnosis were treated with specific drugs; 37 in the acute phase and 48 in the chronic phase. Fifteen chronic assymptomatic patients received a placebo. Treatment in the acute phase led to PCR negative results in 73 percent of the cases, while xenodiagnosis was negative in 86 percent. In the chronic phase, PCR was negative in 65 percent of the patients and 83 percent led to xenodiagnosis negative results. Regarding the untreated group (placebo), 73 percent gave negative results by xenodiagnosis, of which 36 percent were positive by PCR. Individuals that were considered seronegative (n=10), presented unequivocally negative results in the PCR demonstrating the elimination of parasite DNA. Seventeen individuals had their antibodies titers decreased to such a level that the final results were considered as doubtful and 16 of them presented negative PCR. The molecular method represents a clear advantage over conventional techniques to demonstrate persistent infections in Chagas disease patients that underwent chemotherapy