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ABSTRACT Tuberculosis (TB) and infectious diseases caused by non-tuberculous mycobacteria (NTM) are global concerns. The development of a rapid and accurate diagnostic method, capable of detecting and identifying different mycobacteria species, is crucial. We propose a molecular approach, the BiDz-TB/NTM, based on the use of binary deoxyribozyme (BiDz) sensors for the detection of Mycobacterium tuberculosis (Mtb) and NTM of clinical interest. A panel of DNA samples was used to evaluate Mtb-BiDz, Mycobacterium abscessus/Mycobacterium chelonae-BiDz, Mycobacterium avium-BiDz, Mycobacterium intracellulare/Mycobacterium chimaera-BiDz, and Mycobacterium kansasii-BiDz sensors in terms of specificity, sensitivity, accuracy, and limit of detection. The BiDz sensors were designed to hybridize specifically with the genetic signatures of the target species. To obtain the BiDz sensor targets, amplification of a fragment containing the hypervariable region 2 of the 16S rRNA was performed, under asymmetric PCR conditions using the reverse primer designed based on linear-after-the-exponential principles. The BiDz-TB/NTM was able to correctly identify 99.6% of the samples, with 100% sensitivity and 0.99 accuracy. The individual values of specificity, sensitivity, and accuracy, obtained for each BiDz sensor, satisfied the recommendations for new diagnostic methods, with sensitivity of 100%, specificity and accuracy ranging from 98% to 100% and from 0.98 to 1.0, respectively. The limit of detection of BiDz sensors ranged from 12 genome copies (Mtb-BiDz) to 2,110 genome copies (Mkan-BiDz). The BiDz-TB/NTM platform would be able to generate results rapidly, allowing the implementation of the appropriate therapeutic regimen and, consequently, the reduction of morbidity and mortality of patients.IMPORTANCEThis article describes the development and evaluation of a new molecular platform for accurate, sensitive, and specific detection and identification of Mycobacterium tuberculosis and other mycobacteria of clinical importance. Based on BiDz sensor technology, this assay prototype is amenable to implementation at the point of care. Our data demonstrate the feasibility of combining the species specificity of BiDz sensors with the sensitivity afforded by asymmetric PCR amplification of target sequences. Preclinical validation of this assay on a large panel of clinical samples supports the further development of this diagnostic tool for the molecular detection of pathogenic mycobacteria.

Abstract Infection disease caused by nontuberculous mycobacteria (NTM) have been increasingly reported and often manifest with the same symptoms of tuberculosis (TB). The identification of the causative agent is fundamental for the determination of an appropriate therapy, since each species of mycobacteria requires a specific treatment. Thus, rapid and accurate tests to identify mycobacteria of medical interest, such as Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium complex (MAC), are necessary in the clinical routine. The present study evaluated an in-house multiplex PCR to detect, in reference and clinical strains, the genus Mycobacterium and also M. tuberculosis and MAC. To identify the Mycobacterium genus, M. tuberculosis and MAC, it was amplified a fragment of hsp65 gene, esat-6 gene, and the internal transcribed spacer between the 16S and 23S rRNA genes, respectively. In total, 87 mycobacteria strains were used, being 10 reference and 77 clinical strains, previously identified as MTBC (n = 66), M. avium (n = 8) or other NTM specie (n = 13). The hsp65 gene fragment was amplified for all mycobacteria strains evaluated (87/87). This multiplex PCR presented sensitivity of 100% and specificity of 95.2% for M. tuberculosis detection, and sensitivity of 100% and specificity of 100% for MAC detection. The multiplex PCR evaluated is an important tool for the differentiation between M. tuberculosis and NTM, as well as for the identification of MAC, a complex composed by species with high prevalence in the world.

ABSTRACT We conducted a cross-sectional, retrospective study, characterized by classical and molecular epidemiology, involving M. tuberculosis isolates from a regional prison in southern Brazil. Between January of 2011 and August of 2014, 379 prisoners underwent sputum smear microscopy and culture; 53 (13.9%) were diagnosed with active tuberculosis. Of those, 8 (22.9%) presented with isoniazid-resistant tuberculosis. Strain genotyping was carried out by 15-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat analysis; 68.6% of the patients were distributed into five clusters, and 87.5% of the resistant cases were in the same cluster. The frequency of drug-resistant tuberculosis cases and the rate of recent transmission were high. Our data suggest the need to implement an effective tuberculosis control program within the prison system.

Introduction: Tuberculosis (TB) is an ancient contagious disease, and continues to be the leading cause of morbidity and mortality among infectious contagious diseases. It can be considered an occupational infectious disease when it happens in health professionals. These professionals are directly exposed to TB and are considered to be a high risk population for latent tuberculosis infection (LTBI) and active TB. The primary aim of this study was to estimate the prevalence of LTBI among the clinical and administrative staff of an oncology referral hospital in Rio Grande do Sul. The secondary aim of this study was evaluate tuberculin skin test (TST) conversion rate and the risk factors for TST positivity in this population. Methods: A cross-sectional study was carried out in a retrospective cohort with data collected in March 2013 and March 2014. Data of professionals from different hospital units were included. Those with induration ≥ 10 mm were considered as reactors, and conversion rate was assessed by an increase ≥ 10 mm in induration in the second TST compared with the first one. Results: Among the 225 professionals evaluated in 2013, 135 (60%) were reactors and 90 (40%) were non-reactors. The mean age was 32.9 (± 9.55), 176 (78.22%) were female, and most of the reactors worked in the hospital for 4 years or less. Non-reactors in 2013 were recommended to repeat the test in 2014, and the conversion rate was 9.37%. There was no significant difference in prevalence among the different professional categories, and the assessed risk factors were not associated with ILTB. Conclusions: The prevalence of LTBI in the study population was high, reinforcing the need to implement effective control measures to prevent LTBI in the hospital where the study was conducted. Keywords: Latent tuberculosis; occupational risk; tuberculin test; vulnerable populations

ABSTRACT We conducted a cross-sectional, retrospective study, characterized by classical and molecular epidemiology, involving M. tuberculosis isolates from a regional prison in southern Brazil. Between January of 2011 and August of 2014, 379 prisoners underwent sputum smear microscopy and culture; 53 (13.9%) were diagnosed with active tuberculosis. Of those, 8 (22.9%) presented with isoniazid-resistant tuberculosis. Strain genotyping was carried out by 15-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat analysis; 68.6% of the patients were distributed into five clusters, and 87.5% of the resistant cases were in the same cluster. The frequency of drug-resistant tuberculosis cases and the rate of recent transmission were high. Our data suggest the need to implement an effective tuberculosis control program within the prison system.

Abstract Coronavirus disease (COVID-19) is a pandemic caused by a new coronavirus, called SARS-CoV-2. This disease was first identified in December 2019 and rapidly developed into a challenge to the public health systems around the world. In the absence of a vaccine and specific therapies, disease control and promotion of patient health are strongly dependent on a rapid and accurate diagnosis. This review describes the main laboratory approaches to making a diagnosis of COVID-19 and identifying those previously infected with SARS-CoV-2.

Justificativa e objetivos: A vasta biodiversidade amazônica tem sido apontada como uma fonte de produtos naturais candidatos a diversas atividades farmacológicas, principalmente no combate a doenças infecciosas. Algumas espécies, tais como as pertencentes ao gênero Duroia, da família Rubiaceae, têm sido caracterizadas pela produção de metabólitos secundários com propriedades biológicas importantes, porém são escassos os estudos com espécies deste gênero. Desta forma, o objetivo deste estudo foi avaliar a atividade antimicobacteriana, antifúngica e antiparasitária de extratos de D. macrophylla e D. saccifera. Métodos: Foram coletados materiais vegetais de D. macrophylla e D. saccifera na Reserva Florestal A. Ducke em Manaus- AM, a partir dos quais foram preparados extratos diclorometânico, metanólico e aquoso e determinada a concentração inibitória e concentração larvicida mínima. Resultados: No que diz respeito aos extratos de D. saccifera¸ o extrato diclorometânico dos galhos foi o mais ativo frente às espécies fúngicas e as cepas micobacterianas avaliadas. Por outro lado, o extrato metanólico e o diclorometânico das folhas de D. macrophylla, foram os mais ativos frente a Candida sp. e Mycobacterium tuberculosis, respectivamente, porém, nenhum dos seis extratos avaliados apresentaram atividade antiparasitária frente a Toxocara canis. Conclusão: Esses resultados demonstram as propriedades antimicrobianas dessas plantas amazônicas para o desenvolvimento de novas alternativas terapêuticas no tratamento de doenças infecciosas, tais como a tuberculose e candidíase.

In Mycobacterium tuberculosis (Mtb) the detection of single nucleotide polymorphisms (SNPs) is of high importance both for diagnostics, since drug resistance is primarily caused by the acquisition of SNPs in multiple drug targets, and for epidemiological studies in which strain typing is performed by SNP identification. To provide the necessary coverage of clinically relevant resistance profiles and strain types, nucleic acid-based measurement techniques must be able to detect a large number of potential SNPs. Since the Mtb problem is pressing in many resource-poor countries, requiring low-cost point-of-care biosensors, this is a non-trivial technological challenge. This paper presents a proof-of-concept in which we chose simple DNA-DNA hybridization as a sensing principle since this can be transferred to existing low-cost hardware platforms, and we pushed the multiplex boundaries of it. With a custom designed probe set and a physicochemical-driven data analysis it was possible to simultaneously detect the presence of SNPs associated with first- and second-line drug resistance and Mtb strain typing. We have demonstrated its use for the identification of drug resistance and strain type from a panel of phylogenetically diverse clinical strains. Furthermore, reliable detection of the presence of a minority population (

Rationale and Objectives: The key element for the integration of health networks is an effective system of reference and counter reference, understood as a mechanism for mutual referral of patients between different levels of service complexity. Thus, the aim of this study was to identify and analyze the reference system for the referral of patients diagnosed with tuberculosis in the city of Santa Cruz do Sul, Brazil. Methods: The study was conducted by PET Health Surveillance/Tuberculosis at the Reference Unit for Tuberculosis in the municipality (RU-TB). We conducted a descriptive survey study by reviewing the records of patients who underwent treatment for tuberculosis between the years 2007 and 2011. Data were tabulated in Excel and analyzed using SPSS 18.0. Results: A total of 239 medical records were evaluated and of these, 157 (65.7%) had no reference document or any type of referral; 53 (22.2%) had a medical prescription as a way of referral and 29 (12.1%) had the offi cial reference and counter-reference document. Of the 49 documents (20.5%) with information on the health unit that made the referral, 19 (38.8%) patients were referred to less complex units and 30 (61.2%) referred to greater complexity units. The time interval between the referral date and the reference and the start of treatment was 23 days, ranging from 0 to 296 days; the median was 4.5 days and mode was 1. There were no records related to counter-reference. Conclusion: These data show the importance of systems of reference and counter-reference for health networks, and that errors, such as failing in fi lling out these forms by health care professionals, can have an effect on health system users. KEYWORDS: Tuberculosis. Primary Health Care. Access to health services.

O principal elemento para a integração das redes de saúde é um efetivo sistema de referência e contrarreferência, entendido como mecanismo de encaminhamento mútuo de pacientes entre os diferentes níveis de complexidade dos serviços. Dessa forma, o objetivo deste estudo foi conhecer e analisar o sistema de referência para oencaminhamento de pacientes com diagnóstico de tuberculose no município de Santa Cruz do Sul. Métodos: O estudo foi realizado pelo PET- Saúde Vigilância/Tuberculose, na Unidade Referencia para Tuberculose do município (UR-TB). Foi realizado um estudo descritivo do tipo levantamento, através de uma revisão nos prontuários dos pacientes que realizaram tratamento para tuberculose entre os anos de 2007 a 2011. Os dados foram tabulados em Excel e analisados em SPSS 18.0. Resultados: Foram avaliados 239 prontuários, destes 157 (65,7%) não apresentavam documento de referência nem qualquertipo de encaminhamento, 53 (22,2%) apresentavam receituário médico como forma de encaminhamento e 29 (12,1%) continhamo documento oficial de referência e contrarreferência. Entre os 49 (20,5%) documentos que apresentavam informações referentes à unidade de saúde que fez o encaminhamento, 19 (38,8%) pacientes foram encaminhados por unidades de menor complexidade e 30 (61,2%) encaminhados por unidades de maior complexidade. O intervalo de tempo entre a data do encaminhamento para a referência e o início do tratamento foi de 23 dias variando de 0 a 296 dias, a mediana foi de 4,5 dias e a moda foi 1. Nenhum registro referente à contrarreferência foi encontrado. Conclusão: Através destes dados podemos refletir sobre a importância dos sistemas de referência e contrarreferência para as redes de saúde, assim como as falhas queo não preenchimento dessas guias, pelos profissionais, pode acarretar no sistema de saúde prejudicando seus usuários.

No Brasil, a Tuberculose (TB) é um grande problema entre a população privada de liberdade (PPL), sendo a sua magnitude pouco conhecida pela ausência da implantação e segmento de programas de vigilância epidemiológica e controle da TB nesta população. O objetivo deste trabalho foi comparar a prevalência de TB na população geral e entre a PPL nos municípios do estado do Rio Grande do Sul que possuem equipes de saúde prisional implementadas”. Realizou-se um estudo ecológico, utilizando dados do Sistema Nacional de Agravos de Notificação (SINAN), onde avaliou-se o número de casos de TB notificados na população geral e entre a PPL, no período de 2011 a 2013, dos 13 municípios do Rio Grande do Sul (RS) que possuem equipes de saúde prisional. Verificou-se que 7 (53,8%) municípios estudados ampliaram seus registros de notificação de casos de TB após a implementação das equipes de saúde. Entretanto, ainda são necessárias diversas ações neste sentido, entre elas, maior adesão dos procedimentos para controle da tuberculose, a capacitação dos profissionais de saúde para a identificação de sintomáticos respiratórios, realização de triagem entre ingressos e indivíduos já encarcerados e encaminhamento de exames para o diagnóstico precoce da TB.