Evaluación de la prueba de la nitrato reductasa directa en microplaca para la detección rápida de tuberculosis multirresistente y extensamente resistente a fármacos

Introduction: Reports of Mycobacterium tuberculosis resistant to multiple drugs are increasing globally and laboratories are becoming increasingly aware of the need for drug susceptibility testing. In recent years, due to the long time required by conventional drug susceptibility testing, new approaches have been proposed for faster detection of drug resistance, such as the nitrate reductase assay, considered fast and inexpensive, making it a good diagnostic tool for low resource countries.Objective: The present study proposed a fast direct colorimetric drug susceptibility testing method in a microplate format using solid medium.Materials and methods: The diagnostic accuracy was evaluated by comparing the proportion method with the direct nitrate reductase assay in plates. Frozen sputum samples, known to be positive, were decontaminated and processed by Petroff method. The decontaminated suspension was used to perform direct nitrate reductase assay in 7H11 medium using 1 μg/ml rifampicin (RIF), 0.2 μg/ml isoniazid (INH), 2 μg/ml ofloxacin (OFX), 6 μg/ml kanamycin (KAN), 2 μg/ml amikacin (AMK) and 10 μg/ml capreomycin (CAP). Eighty-four samples were tested and the results for 69% of them were available within 21 days.Results: The sensitivity and specificity compared to the proportion method, was 98.5% and 100% for INH, 98.3% and 96.2% for RIF, 91.7% and 100% for KAN, 78.8% and 97.3% for OFX, 100% and 100% for AMK and CAP, respectively.Conclusion: The results lead to the conclusion that direct nitrate reductase assay, in this new format, is an accurate, quick and inexpensive method to determine the susceptibility profile of M. tuberculosis and may become an alternative for countries with limited resources.Introducción. Los informes sobre Mycobacterium tuberculosis resistente a múltiples fármacos están aumentando a nivel mundial y los laboratorios toman cada vez más conciencia sobre la necesidad de realizar pruebas de sensibilidad a fármacos. Debido al tiempo prolongado que se requiere para hacerlas, se han propuesto nuevos enfoques para la detección rápida de resistencia a los medicamentos, tales como la prueba de la nitrato reductasa.Objetivo. En este estudio se propuso una prueba de sensibilidad a fármacos colorimétrica, rápida y directa, en un formato de microplacas utilizando medio sólido.Materiales y métodos. La precisión del diagnóstico se evaluó mediante la comparación del método de las proporciones con la prueba de la nitrato reductasa directa en placas. Se descontaminaron muestras positivas congeladas de esputo y se procesaron mediante el método de Petroff. La suspensión ya descontaminada se utilizó para hacer la prueba de la nitrato reductasa directa en medio 7H11, utilizando 1 μg/ml de rifampicina, 0,2 μg/ml de isoniacida, 2 μg/ml de ofloxacina, 6 μg/ml de de kanamicina, 2 μg/ ml de amicacina y 10 μg/ml de capreomicina. Se analizaron 84 muestras y los resultados del 69 % de ellas estuvieron disponibles en 21 días.Resultados. La sensibilidad y la especificidad de la prueba comparada con el método de las proporciones fueron de 98,5 y 100 % para la isoniacida, de 98,3 y 96,2 % para la rifampicina, de 91,7 y 100 para la kanamicina, de 78,8 y 97,3 % para la ofloxacina y de 100 y 100 % para la amikacina y la capremicina, respectivamente.Conclusión. Este nuevo formato de la prueba de la nitrato reductasa directa es un método preciso, rápido y económico para determinar el perfil de sensibilidad de M. tuberculosis y puede convertirse en una alternativa para los países con recursos limitados

Clonal expansion across the seas as seen through CPLP-TB database: A joint effort in cataloguing Mycobacterium tuberculosis genetic diversity in Portuguese-speaking countries

This is an open access article under the CC BY license (http://creativecommons.org/licenses/BY/4.0/).Tuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. To address this, we have assembled and analysed the largest CPLP M. tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. The data herein presented reinforces Latin American and Mediterranean (LAM) strains as the hallmark of M. tuberculosis populational structure in the CPLP coupled with country-specific differential prevalence of minor clades. Moreover, using high-resolution typing by 24-loci MIRU-VNTR, six cross-border genetic clusters were detected, thus supporting recent clonal expansion across the Lusophone space. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. As a public health tool, it is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting the risk assessment of strain-specific trends.info:eu-repo/semantics/publishedVersio

Clonal expansion across the seas as seen through CPLP-TB database: A joint effort in cataloguing Mycobacterium tuberculosis genetic diversity in Portuguese-speaking countries.

Tuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. To address this, we have assembled and analysed the largest CPLP M. tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. The data herein presented reinforces Latin American and Mediterranean (LAM) strains as the hallmark of M. tuberculosis populational structure in the CPLP coupled with country-specific differential prevalence of minor clades. Moreover, using high-resolution typing by 24-loci MIRU-VNTR, six cross-border genetic clusters were detected, thus supporting recent clonal expansion across the Lusophone space. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. As a public health tool, it is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting the risk assessment of strain-specific trends

uma nova ferramenta de vigilância transnacional da tuberculose no espaço lusófono

A Tuberculose (TB) permanece um grave problema de saúde pública na Comunidade dos Países de Língua Portuguesa (CPLP). Apesar da ampla variância da incidência da TB nos seus estados-membro e de um fluxo migratório contínuo entre os países que integram este grupo, existe uma enorme lacuna no que diz respeito ao conhecimento da estrutura populacional conjunta do Mycobacterium tuberculosis e circulação de estirpes entre estes países. Para fazer face a esta necessidade, foi agregado e analisado o maior conjunto de dados respeitante à diversidade genotípica e resistência fenotípica na CPLP que compreende um total de 1447 isolados clínicos, incluindo 423 isolados multirresistentes de cinco países da CPLP. Por forma a tornar estes dados disponíveis para a comunidade científica e autoridades de saúde pública, foi desenvolvida a CPLP-TB (disponível em http://cplp-tb.ff.ulisboa.pt), uma base de dados disponível online e provida de aplicativos para análise exploratória do conteúdo. Como ferramenta de saúde pública, espera-se que venha a contribuir para um conhecimento mais aprofundado da estrutura populacional do M. tuberculosis e circulação de estirpes na CPLP de forma a apoiar a avaliação de risco e tendências específicas para diversos clones. Tuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. To address this, we have assembled and analyzed the largest CPLP M . tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. As a public health tool, it is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting the risk assessment of strain-specific trends.publishersversionpublishe

Análise bacteriológica de casos de aderência pulmonar em suínos de diferentes lotes abatidos em um frigorífico no Rio Grande do Sul

Bacteriological analysis were performed on 123 lungs in pulmonary cases of adherence in pig carcasses from 59 different farms at an abattoir in Rio Grande do Sul, Brazil. After classification by the Federal Inspection Service, were collected 49 samples of lungs from carcasses free for comsumption, 45 destined to consumption after heat treatment and 29 from condemned carcasses. Bacteriological examination revealed Pasteurella multocida as the most frequent bacteria isolated (61 samples) followed by Arcanobacterium pyogenes (52 samples), also occurring coinfections with these microorganisms. Capsular type A of P. multocida were prevalent (44 isolates). Other microorganisms also isolated were Actinobacillus pleuropneumoniae (4 samples), Haemophilus parasuis (2), Streptococcus suis (5), beta haemolytic Streptococcus (4), Nocardia sp (3), Aeromonas sp (1), Staphylococcus sp (1) with negative results on 20 materials. Isolates of P. multocida revealed high susceptibility to antimicrobials on gel diffusion, being only two samples resistant to oxitetracyclin and three intermediary for streptomycin, one resistant and other intermediary to trimetoprim-sulphonamide.Bacteriological analysis were performed on 123 lungs in pulmonary cases of adherence in pig carcasses from 59 different farms at an abattoir in Rio Grande do Sul, Brazil. After classification by the Federal Inspection Service, were collected 49 samples of lungs from carcasses free for comsumption, 45 destined to consumption after heat treatment and 29 from condemned carcasses. Bacteriological examination revealed Pasteurella multocida as the most frequent bacteria isolated (61 samples) followed by Arcanobacterium pyogenes (52 samples), also occurring coinfections with these microorganisms. Capsular type A of P. multocida were prevalent (44 isolates). Other microorganisms also isolated were Actinobacillus pleuropneumoniae (4 samples), Haemophilus parasuis (2), Streptococcus suis (5), beta haemolytic Streptococcus (4), Nocardia sp (3), Aeromonas sp (1), Staphylococcus sp (1) with negative results on 20 materials. Isolates of P. multocida revealed high susceptibility to antimicrobials on gel diffusion, being only two samples resistant to oxitetracyclin and three intermediary for streptomycin, one resistant and other intermediary to trimetoprim-sulphonamid

The BACTEC MGIT(tm) 320 system as a laboratory tool to diagnose tuberculosis in a Brazilian hospital with a high prevalence of HIV infection

Abstract: INTRODUCTION: The World Health Organization endorses the BACTEC Mycobacterial Growth Indicator Tube (MGIT)(tm) system as a rapid, sensitive, and specific method to diagnostic of tuberculosis. Here, we compared the performance of this system against Ogawa-Kudoh cultures and microscopy. METHODS: A total of 927 samples were obtained between December 2011 and December 2013 from 652 cases of suspected tuberculosis at the School Hospital of the Federal University of Rio Grande in Brazil. RESULTS: The MGIT system confirmed tuberculosis in more cases in less time. CONCLUSIONS: The MGIT system is an effective tool for early diagnosis of tuberculosis, especially in patients with HIV/AIDS

Isolamento de Salmonella Braenderup em arara-azul (Anodorhynchus hyacinthinus) Salmonella Braenderup isolation in Hyacinth macaw (Anodorhynchus hyacinthinus)

O monitoramento sanitário de populações de arara-azul (Anodorhynchus hyacinthinus) de vida livre visa a permitir ajustes de manejo em ambiente natural alterado. Para avaliar a ocorrência de Salmonella spp. em filhotes dessa espécie, foram coletados swabs de cloaca no Pantanal de Miranda, Mato Grosso do Sul (MS). Uma colônia morfológica e bioquimicamente compatível com Salmonella spp. foi isolada e sorotipada como Salmonella Braenderup. Devido ao alto potencial zoonótico desse microrganismo, é importante o controle sanitário de psitacídeos em vida livre. Na literatura pesquisada não foi encontrado relato sobre o isolamento dessa bactéria em arara-azul, tanto em vida livre, como em cativeiro.The sanitary monitoring of free-living Hyacinth macaw (Anodorhynchus hyacinthinus) allows adjusting the management in altered natural habitat. To evaluate the occurrence of Salmonella spp. it was collected cloacal swabs of this nestlings species, in the Pantanal wetlands, in the state of Mato Grosso do Sul, Brazil. One Salmonella-like colony was serologically typed and identified as Salmonella Braenderup. Due to the high zoonotical potential of this microorganism, it is important an effective sanitary control of wildlife psittacines. In the literature searched it was not found any report on isolation of this bacterium in Hyacinth macaw for both free-living and captive animals

Mycobacterium tuberculosis genetic diversity and drug resistance across Portuguese-speaking countries and CPLP-TB: a novel framework and surveillance tool for the Lusophone community

Background: Tuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. Materials and Methods: To address this, we have assembled and analyzed the largest CPLP M. tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. Genotyping analysis was carried out by 15/24 Mycobacterial Interspersed Repetitive Unit – Variable Number of Tandem Repeat (MIRU-VNTR) and Spoligotyping. Drug Susceptibility testing was performed using standardized BACTEC 960 MGIT methodology or through the resazurin microtiter assay (REMA). Results: The data herein presented reinforces Latin American and Mediterranean (LAM) strains as the hallmark of M. tuberculosis populational structure in the CPLP coupled with country-specific differential prevalence of minor clades. Moreover, using high-resolution typing by 24-loci MIRU-VNTR, six cross-border genetic clusters were detected, thus supporting recent clonal expansion across the Lusophone space. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. Conclusions: As a public health tool, CPLP-TB is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting risk assessment of strain-specific trends.N/