Diretriz da Sociedade Brasileira de Cardiologia sobre Diagnóstico e Tratamento de Pacientes com Cardiomiopatia da Doença de Chagas

This guideline aimed to update the concepts and formulate the standards of conduct and scientific evidence that support them, regarding the diagnosis and treatment of the Cardiomyopathy of Chagas disease, with special emphasis on the rationality base that supported it.  Chagas disease in the 21st century maintains an epidemiological pattern of endemicity in 21 Latin American countries. Researchers and managers from endemic and non-endemic countries point to the need to adopt comprehensive public health policies to effectively control the interhuman transmission of T. cruzi infection, and to obtain an optimized level of care for already infected individuals, focusing on diagnostic and therapeutic opportunistic opportunities.   Pathogenic and pathophysiological mechanisms of the Cardiomyopathy of Chagas disease were revisited after in-depth updating and the notion that necrosis and fibrosis are stimulated by tissue parasitic persistence and adverse immune reaction, as fundamental mechanisms, assisted by autonomic and microvascular disorders, was well established. Some of them have recently formed potential targets of therapies.  The natural history of the acute and chronic phases was reviewed, with enhancement for oral transmission, indeterminate form and chronic syndromes. Recent meta-analyses of observational studies have estimated the risk of evolution from acute and indeterminate forms and mortality after chronic cardiomyopathy. Therapeutic approaches applicable to individuals with Indeterminate form of Chagas disease were specifically addressed. All methods to detect structural and/or functional alterations with various cardiac imaging techniques were also reviewed, with recommendations for use in various clinical scenarios. Mortality risk stratification based on the Rassi score, with recent studies of its application, was complemented by methods that detect myocardial fibrosis.  The current methodology for etiological diagnosis and the consequent implications of trypanonomic treatment deserved a comprehensive and in-depth approach. Also the treatment of patients at risk or with heart failure, arrhythmias and thromboembolic events, based on pharmacological and complementary resources, received special attention. Additional chapters supported the conducts applicable to several special contexts, including t. cruzi/HIV co-infection, risk during surgeries, in pregnant women, in the reactivation of infection after heart transplantation, and others.     Finally, two chapters of great social significance, addressing the structuring of specialized services to care for individuals with the Cardiomyopathy of Chagas disease, and reviewing the concepts of severe heart disease and its medical-labor implications completed this guideline.Esta diretriz teve como objetivo principal atualizar os conceitos e formular as normas de conduta e evidências científicas que as suportam, quanto ao diagnóstico e tratamento da CDC, com especial ênfase na base de racionalidade que a embasou. A DC no século XXI mantém padrão epidemiológico de endemicidade em 21 países da América Latina. Investigadores e gestores de países endêmicos e não endêmicos indigitam a necessidade de se adotarem políticas abrangentes, de saúde pública, para controle eficaz da transmissão inter-humanos da infecção pelo T. cruzi, e obter-se nível otimizado de atendimento aos indivíduos já infectados, com foco em oportunização diagnóstica e terapêutica. Mecanismos patogênicos e fisiopatológicos da CDC foram revisitados após atualização aprofundada e ficou bem consolidada a noção de que necrose e fibrose sejam estimuladas pela persistência parasitária tissular e reação imune adversa, como mecanismos fundamentais, coadjuvados por distúrbios autonômicos e microvasculares. Alguns deles recentemente constituíram alvos potenciais de terapêuticas. A história natural das fases aguda e crônica foi revista, com realce para a transmissão oral, a forma indeterminada e as síndromes crônicas. Metanálises recentes de estudos observacionais estimaram o risco de evolução a partir das formas aguda e indeterminada e de mortalidade após instalação da cardiomiopatia crônica. Condutas terapêuticas aplicáveis aos indivíduos com a FIDC foram abordadas especificamente. Todos os métodos para detectar alterações estruturais e/ou funcionais com variadas técnicas de imageamento cardíaco também foram revisados, com recomendações de uso nos vários cenários clínicos. Estratificação de risco de mortalidade fundamentada no escore de Rassi, com estudos recentes de sua aplicação, foi complementada por métodos que detectam fibrose miocárdica. A metodologia atual para diagnóstico etiológico e as consequentes implicações do tratamento tripanossomicida mereceram enfoque abrangente e aprofundado. Também o tratamento de pacientes em risco ou com insuficiência cardíaca, arritmias e eventos tromboembólicos, baseado em recursos farmacológicos e complementares, recebeu especial atenção. Capítulos suplementares subsidiaram as condutas aplicáveis a diversos contextos especiais, entre eles o da co-infecção por T. cruzi/HIV, risco durante cirurgias, em grávidas, na reativação da infecção após transplante cardíacos, e outros.    Por fim, dois capítulos de grande significado social, abordando a estruturação de serviços especializados para atendimento aos indivíduos com a CDC, e revisando os conceitos de cardiopatia grave e suas implicações médico-trabalhistas completaram esta diretriz.&nbsp

Deep Sequencing of the Trypanosoma cruzi GP63 Surface Proteases Reveals Diversity and Diversifying Selection among Chronic and Congenital Chagas Disease Patients

International audienceBackgroundChagas disease results from infection with the diploid protozoan parasite Trypanosoma cruzi. T. cruzi is highly genetically diverse, and multiclonal infections in individual hosts are common, but little studied. In this study, we explore T. cruzi infection multiclonality in the context of age, sex and clinical profile among a cohort of chronic patients, as well as paired congenital cases from Cochabamba, Bolivia and Goias, Brazil using amplicon deep sequencing technology.Methodology/ Principal FindingsA 450bp fragment of the trypomastigote TcGP63I surface protease gene was amplified and sequenced across 70 chronic and 22 congenital cases on the Illumina MiSeq platform. In addition, a second, mitochondrial target—ND5—was sequenced across the same cohort of cases. Several million reads were generated, and sequencing read depths were normalized within patient cohorts (Goias chronic, n = 43, Goias congenital n = 2, Bolivia chronic, n = 27; Bolivia congenital, n = 20), Among chronic cases, analyses of variance indicated no clear correlation between intra-host sequence diversity and age, sex or symptoms, while principal coordinate analyses showed no clustering by symptoms between patients. Between congenital pairs, we found evidence for the transmission of multiple sequence types from mother to infant, as well as widespread instances of novel genotypes in infants. Finally, non-synonymous to synonymous (dn:ds) nucleotide substitution ratios among sequences of TcGP63Ia and TcGP63Ib subfamilies within each cohort provided powerful evidence of strong diversifying selection at this locus.Conclusions/SignificanceOur results shed light on the diversity of parasite DTUs within each patient, as well as the extent to which parasite strains pass between mother and foetus in congenital cases. Although we were unable to find any evidence that parasite diversity accumulates with age in our study cohorts, putative diversifying selection within members of the TcGP63I gene family suggests a link between genetic diversity within this gene family and survival in the mammalian host

The Trypanosoma cruzi Satellite DNA OligoC-TesT and Trypanosoma cruzi Kinetoplast DNA OligoC-TesT for Diagnosis of Chagas Disease: A Multi-cohort Comparative Evaluation Study

Artículo de publicación ISIBackground: The Trypanosoma cruzi satellite DNA (satDNA) OligoC-TesT is a standardised PCR format for diagnosis of Chagas disease. The sensitivity of the test is lower for discrete typing unit (DTU) TcI than for TcII-VI and the test has not been evaluated in chronic Chagas disease patients. Methodology/Principal Findings: We developed a new prototype of the OligoC-TesT based on kinetoplast DNA (kDNA) detection. We evaluated the satDNA and kDNA OligoC-TesTs in a multi-cohort study with 187 chronic Chagas patients and 88 healthy endemic controls recruited in Argentina, Chile and Spain and 26 diseased non-endemic controls from D.R. Congo and Sudan. All specimens were tested in duplicate. The overall specificity in the controls was 99.1% (95% CI 95.2%–99.8%) for the satDNA OligoC-TesT and 97.4% (95% CI 92.6%–99.1%) for the kDNA OligoC-TesT. The overall sensitivity in the patients was 67.9% (95% CI 60.9%–74.2%) for the satDNA OligoC-TesT and 79.1% (95% CI 72.8%–84.4%) for the kDNA OligoC-Test. Conclusions/Significance: Specificities of the two T. cruzi OligoC-TesT prototypes are high on non-endemic and endemic controls. Sensitivities are moderate but significantly (p = 0.0004) higher for the kDNA OligoC-TesT compared to the satDNA OligoC-TesT.This work was financially supported by the European Commission Seventh Framework Programme, ChagasEpiNet project, grant number 223034

Samples provenance and symptoms.

<p>^a Samples from Goias congenital case</p><p>^x Samples from the same patient taken >12 months apart</p><p>^y Samples from the same patient taken < 6 months apart</p><p>^z Samples taken from the same patient >12 months apart</p><p>Samples provenance and symptoms.</p

Alpha diversity indices for TcGP63I amplicon diversity derived from pairs of congenital Chagas disease cases.

<p>Diversity indices were derived from STs defined at 99% sequence similarity. Bar plot and associated <i>x</i>-axis on the right hand side shows the Shannon diversity index calculated in Mothur [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003458#pntd.0003458.ref034" target="_blank">34</a>], with error bars defining upper and lower 95% confidence intervals.</p

Yang and Neilson estimates for positive selection within and among abundant 97% STs identified in this study.

<p>^a Numbers in brackets represent the number of 99% STs define within each cluster from which estimates were generated.</p><p>^b P values are give for Fisher’s exact tests for deviation from the neutral expectation of Ka/Ks = 0.</p><p>Yang and Neilson estimates for positive selection within and among abundant 97% STs identified in this study.</p

Bar plot showing sequence type identity and abundance defined at 97% similarity for the ND5 locus across all samples.

<p>A—Goias cohort chronic/intermediate cases; B—Cochabamba chronic/intermediate cases; C—Cochabamba congenital cases. Y axes show log transformed abundance (read counts). X axes show clustered bars for individual samples. Sequence type identities are given in the legend. Stars denote congenital pair from Goias. Labels x (6416 / 6452), y (6401 / 6536) and z (6379 / 6445) sample pairs from the same patient at different time points (see <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003458#pntd.0003458.t001" target="_blank">Table 1</a>).</p

Principal coordinates analysis of sequence diversity between chronic Chagas Disease patient TcGP63I antigenic repertoires.

<p>Genetic distances are based on a weighted unifrac metric. Plot A shows diversity comparisons among Go-as asymptomatic (asympt) and symptomatic (sympt) clinical cases, as well as one acute case. Plot B shows Goias cases with symptoms categorised as acute, card (cardiopathy), card + mega (cardiopathy as well as megacolon and / or megaesophagous), mega (megacolon and / or megaesophagous) or asympt (asymptomatic). Plot C shows comparisons among Cochabamba clinical cases (not including congenital cases) classified as either asymptomatic (asympt) and symptomatic (sympt). The dashed circle on plot C indicates samples unambiguously defined as TcI at the ND5 locus. Pairs of sequential isolates from the same patient are labelled x and y respectively.</p

Analytical sensitivity and analytical specificity of the <i>T. cruzi</i> satDNA OligoC-TesT and kDNA OligoC-TesT on DNA from 6 <i>T. cruzi</i> and 3 <i>T. rangeli</i> reference strains.

<p>DTU = discrete typing unit, NA = not applicable.</p