Comparison of different diagnostic modalities for isolation of Mycobacterium Tuberculosis among suspected tuberculous lymphadenitis patients / Comparação de diferentes modalidades de diagnóstico para isolamento de Mycobacterium tuberculosis entre pacientes com suspeita de linfadenite tuberculosa

Abstract Tuberculosis is a communicable disease with high morbidity and mortality rates in developing countries. The study's primary objective is to compare conventional methods such as acid-fast bacillus (AFB) culture and microscopy with rapid diagnostic methods. The secondary objective is to compare histopathological and microbiological findings in suspected patients with tubercular lymphadenitis. A total of 111 samples (August 2018 to September 2019) of lymph nodes were processed for AFB microscopy, AFB cultures, drug-susceptibility testing (DST), histopathology, and Xpert Mycobacterium Tuberculosis (MTB)/resistance to Rifampin (RIF) assays. Out of 111 lymph node samples, 6 (5.4%) were positive for AFB smear microscopy, 84 (75.6%) were positive for AFB culture, 80 (70.7%) were positive on Gene Xpert, and 102 (91.8%) were indicative of tuberculosis for histopathology studies. Mycobacteria growth indicator tube (MGIT) culture positivity was 84 (75.6%) higher than solid Lowenstein-Jensen (LJ) culture 74 (66.6%). Positive cultures underwent phenotypic DST. Two cases were Multidrug-resistant (MDR) on DST, while three cases were Rifampicin resistant on Gene Xpert. The sensitivity of Genexpert was (62%) against the conventional AFB culture method. The poor performance of conventional lymphadenitis diagnostic methods requires early and accurate diagnostic methodology. Xpert MTB/RIF test can help in the treatment of multidrug-resistant TB cases. Nonetheless, rapid and conventional methods should be used for complete isolation of Mycobacterium tuberculosis.

Resumo A tuberculose é uma doença transmissível com altas taxas de morbimortalidade nos países em desenvolvimento. O objetivo principal do estudo é comparar métodos convencionais, como cultura de bacilo álcool-ácido resistente (BAAR) e microscopia, com métodos de diagnóstico rápido. O objetivo secundário é comparar os achados histopatológicos e microbiológicos em pacientes com suspeita de linfadenite tubercular. Um total de 111 amostras (agosto de 2018 a setembro de 2019) de gânglios linfáticos foi processado ​​para microscopia de AFB, culturas de AFB, teste de susceptibilidade a drogas (DST), histopatologia e Xpert Mycobacterium tuberculosis (MTB)/ensaios de resistência à rifampicina (RIF). Das 111 amostras de linfonodos, 6 (5,4%) foram positivas para baciloscopia de AFB, 84 (75,6%) foram positivas para cultura de AFB, 80 (70,7%) foram positivas para o GeneXpert e 102 (91,8%) foram indicativas de tuberculose para estudos histopatológicos. A positividade da cultura do tubo indicador de crescimento de micobactérias (MGIT) foi 84 (75,6%), maior que a cultura sólida de Lowenstein-Jensen (LJ), 74 (66,6%). As culturas positivas foram submetidas a DST fenotípico. Dois casos eram multirresistentes (MDR) ao DST, enquanto três casos eram resistentes à rifampicina no GeneXpert. A sensibilidade do GeneXpert foi 62% contra o método convencional de cultura AFB. O fraco desempenho dos métodos convencionais de diagnóstico de linfadenite requer metodologia de diagnóstico precoce e precisa. O teste Xpert MTB/RIF pode ajudar no tratamento de casos de tuberculose multirresistente. No entanto, métodos rápidos e convencionais devem ser usados ​​para o isolamento completo do Mycobacterium tuberculosis.

Comparative study of RFLP-IS6110 and MIRU-VNTR from Mycobacterium tuberculosis isolated in the state of Minas Gerais, Brazil

DNA genotyping of Mycobacterium tuberculosis has been widely applied in the understanding of disease transmission in many countries. The purpose of this study was to genotype the strains of M. tuberculosis isolated in patients with new tuberculosis (TB) cases in Minas Gerais, as well as to compare the similarity, discriminatory power, and agreement of the clusters between the IS6110 Restriction Fragment Length Polymorfism (RFLP) and 12 loci Variable Number Tandem Repeat - Mycobacterial Interspersed Repetitive Units (MIRU-VNTR) techniques. It was observed that 32% (66/204) of the isolated strains in the RFLP-IS6110 and 50.9% (104/204) of the isolated strains in the MIRU-VNTR presented a similarity of equal to or above 85%. The RFLP-IS6110 and MIRU-VNTR proved to contain a high discriminatory power. The similarity index resulting from the RFLP showed no recent transmission. Good agreement was observed between the techniques when clusters were detected; however, the best epidemiological relationship was found when using the RFLP-IS6110.(AU)

Tuberculosis caused by Mycobacterium tuberculosis complex in a captive tapir (Tapirus terrestris)

Background: Tuberculosis is an infectious disease caused by the Mycobacterium tuberculosis complex has already been identified in a great number of wild species. Captive animals may have a potential source for zoonoses, because is related to factors such as cohabitation, direct contact with the public, presence of biological vectors, nutritional deficiencies, absence of sanitary barriers, precautionary hygienic measures and sanitary vigilance. In Brazil, there is little information on tuberculosis in captivity animals, and little attention is given to the risks of disease transmission from humans. The aim of this study was to report the first diagnosed case of tuberculosis Tapirus terrestris in Brazilian Amazon region.Case: One Tapirus terrestris was kept by local zoobotanic foundation in city of Marabá, Southeast of Pará state, Brazilian Amazon, and became ill. Physical examination revealed cough, sneezing, nasal outflow, dyspnea, hyperthermia and lethargy, leading to death. Necropsy demonstrated severe pulmonary alterations: thickening of the inter-alveolar septa, alveolar emphysema, and miliary nodules with dimensions up to 5 mm, which were yellowish-white, caseous, and sometimes calcified. Additionally, large areas of caseous compaction of the parenchyma, characteristic of caseous tuberculosis. Histopathological analysis revealed a process characteristic of mycobacterial infection, with alveoli filled with caseous exudate and thickened septa and fibrocytes, in addition to recently formed tubercles, some with caseous necrosis, calcifications and Langhans cells. In the Ziehl-Neelsen staining, alcohol-acid resistant bacilli were observed in the mesenteric lymph nodes. No mycobacterial growth was observed in Lowenstein-Jensen culture medium. A nested PCR followed by a sequencing assay targeting the hsp65 gene and M. tuberculosis complex member was detected. Water and M. tuberculosis H37Rv were used as negative and positive controls, respectively.[...](AU)

Tuberculosis caused by Mycobacterium tuberculosis complex in a captive tapir (Tapirus terrestris)

Background: Tuberculosis is an infectious disease caused by the Mycobacterium tuberculosis complex has already been identified in a great number of wild species. Captive animals may have a potential source for zoonoses, because is related to factors such as cohabitation, direct contact with the public, presence of biological vectors, nutritional deficiencies, absence of sanitary barriers, precautionary hygienic measures and sanitary vigilance. In Brazil, there is little information on tuberculosis in captivity animals, and little attention is given to the risks of disease transmission from humans. The aim of this study was to report the first diagnosed case of tuberculosis Tapirus terrestris in Brazilian Amazon region.Case: One Tapirus terrestris was kept by local zoobotanic foundation in city of Marabá, Southeast of Pará state, Brazilian Amazon, and became ill. Physical examination revealed cough, sneezing, nasal outflow, dyspnea, hyperthermia and lethargy, leading to death. Necropsy demonstrated severe pulmonary alterations: thickening of the inter-alveolar septa, alveolar emphysema, and miliary nodules with dimensions up to 5 mm, which were yellowish-white, caseous, and sometimes calcified. Additionally, large areas of caseous compaction of the parenchyma, characteristic of caseous tuberculosis. Histopathological analysis revealed a process characteristic of mycobacterial infection, with alveoli filled with caseous exudate and thickened septa and fibrocytes, in addition to recently formed tubercles, some with caseous necrosis, calcifications and Langhans cells. In the Ziehl-Neelsen staining, alcohol-acid resistant bacilli were observed in the mesenteric lymph nodes. No mycobacterial growth was observed in Lowenstein-Jensen culture medium. A nested PCR followed by a sequencing assay targeting the hsp65 gene and M. tuberculosis complex member was detected. Water and M. tuberculosis H37Rv were used as negative and positive controls, respectively.[...]

Antimicrobial activity of essential oils from Lippia alba, Lippia sidoides, Cymbopogon citrates, Plectranthus amboinicus, and Cinnamomum zeylanicum against Mycobacterium tuberculosis / Atividade antimicrobiana de leos essenciais de Lippia alba, Lippia sidoides, Cymbopogon citrates, Plectranthus amboinicus, e Cinnamomum zeylanicum em Mycobacterium tuberculosis

The rise in cases of antibiotic-resistant Mycobacterium tuberculosis has become a major obstacle to the effective control of tuberculosis (TB) worldwide. Essential oils (EO) are complex mixtures that may contain between 20 and 60 components, with two or three major compounds at relatively high concentrations (20-70%) that are responsible for their pharmacological properties. The objective of this study was to assess the antimicrobial activity of the EOs, bushy lippia (Lippia alba), rosemary pepper (Lippia sidoides), lemon grass (Cymbopogon citratus), Mexican mint or Indian borage (Plectranthus amboinicus), and true cinnamon (Cinnamomum zeylanicum), against Mycobacterium tuberculosis H37Rv. Chemical characterization of the EOs was performed by gas chromatography coupled to mass spectrometry. The minimum inhibitory concentration (MIC) was determined by the microdilution-based resazurin microtiter assay. Four EOs were able to inhibit the growth of M. tuberculosis, with MICs of 286.5±130.2g/mL (C. zeylanicum), 299.5±117.2g/mL (L. sidoides), 351.6±39.06g/mL (P. amboinicus), and 1,250g/mL (C. citratus). Only the EO of L. alba showed no antimycobacterial activity at the tested concentrations, with an MIC greater than 1,250µg/mL. Results of this study suggested that C. zeylanicum, L. sidoides, and P. amboinicus could be important sources of bactericidal compounds against M. tuberculosis and require further investigation. The activity against M. tuberculosis of these three EOs has not been reported previously. The results show the high potential of the tested antimycobacterial EOs, making them a promising alternative for TB treatment. This data also confirms the importance of bioprospecting studies for active substances with antimycobacterial activity, which are still scarce.(AU)

O aumento no número de casos de Mycobacterium tuberculosis resistentes tem se tornado um grande obstáculo no controle efetivo da tuberculose (TB) mundialmente. Os óleos essenciais (OE), que são misturas complexas que podem conter entre 20 a 60 componentes, apresentam dois ou três compostos principais, em concentrações relativamente elevadas, 20 a 70%, que são responsáveis pelas suas propriedades farmacológicas. O objetivo deste estudo foi avaliar a atividade antimicobacteriana dos seguintes óleos essenciais (OEs) em Mycobacterium tuberculosis H37Rv: erva-cidreira (Lippia alba), alecrim-pimenta (Lippia sidoides), capim-limão (Cymbopogon citratus), orégano (Plectranthus amboinicus) e canela (Cinnamomum zeylanicum). A caracterização química dos OEs foi realizada por cromatografia gasosa acoplada a espectrometria de massa. A Concentração Inibitória Mínima (CIM) foi determinada pela técnica de microdiluição da resazurina. Quatro OEs foram capazes de inibir o crescimento de M. tuberculosis, com CIM de 286,5±130,2g/mL (C. zeylanicum), 299,5±117,2g/mL (L. sidoides), 351,6±39,06g/mL (P. amboinicus) e 1250g/mL (C. citratus). Somente o OE de L. alba não mostrou atividade antimicobacteriana nas conscentrações testadas, considerando CIM maiores que 1250µg/mL. Os resultados deste estudo sugerem que L. sidoides, C. zeylanicum e P. amboinicus podem ser fontes importantes de compostos bactericidas contra M. tuberculosis e prováveis candidatos a serem investigados. A atividade contra M. tuberculosis desses três OEs não foi relatada em estudos anteriores. Os resultados mostram o elevado potencial antimicobacteriano dos OEs analisados, fazendo deles uma alternativa promissora para o tratamento da TB. Os resultados obtidos demonstraram a importância de pesquisas para bioprospecção de substâncias ativas com ação antimicobacteriana, que ainda são escassas.(AU)

Tuberculosis of the central nervous system in cattle in Paraíba, Brazil / Tuberculose no sistema nervoso central de bovinos na Paraíba

This paper describes six cases of tuberculosis in the central nervous system (CNS) of cattle in the state of Paraíba in northeastern Brazil. We reviewed the autopsy reports of 851 bovine necropsies performed from 2003 to 2016. Seventy-three (8.6%) cattle were diagnosed with tuberculosis and six showed lesions in the CNS. Three cases affected cattle up to two-year-old and other three affected adults. Three cattle presented exclusively nervous signs, two had respiratory signs and weight loss and one did not present any clinical signs. At necropsy, five cattle had thickening of the leptomeninges of the cerebellum, pons, obex, spinal cord and cortex, mainly, in the region near the brain basilar Willis´ circle. Another animal, presented a single focal lesion in the cerebellum. Microscopically we observed moderate to severe granulomatous meningitis and encephalitis. Five cattle presented lesions in the lungs and mediastinal lymph nodes and three of them had disseminated lesions in other organs. In all cattle acid-fast bacilli were observed in the lesions and marked positive for immunohistochemistry with polyclonal antibody anti-Mycobacterium tuberculosis. It is concluded that bovine tuberculosis of central nervous system occurs sporadically in Paraíba, in cattle of different ages, most of them with disseminate lesions in other organs. The location of the lesions suggests that the agent invaded the brain by hematogenous route through the circle of Willis.(AU)

Descrevem-se seis casos de tuberculose no sistema nervoso central (SNC) em bovinos, no semiárido da Paraíba. Foram revisados os laudos de um total de 851 necropsias de bovinos realizadas no período de 2003 a 2016. Destes, 73 (8,6%) foram diagnosticados com tuberculose e seis apresentavam lesões no SNC. Três casos ocorreram em bovinos de até dois anos de idade e três em bovinos adultos. Três bovinos apresentaram exclusivamente sinais nervosos, dois tinham sinais respiratórios e perda de peso e um não apresentava nenhum sinal clínico. Macroscopicamente, em cinco bovinos, havia espessamento das leptomeninges do cerebelo, medula espinhal, ponte, obex, colículos e córtex, principalmente, na região basilar encefálica próxima ao polígono de Willis. Em apenas um bovino houve a presença de tubérculo único no cerebelo. Microscopicamente observou-se moderada a acentuada meningite e encefalite granulomatosa. Cinco bovinos apresentaram lesões pulmonares e nos gânglios mediastínicos e três deles tinham lesões disseminadas em outros órgãos. Em todos os bovinos foram encontrados bacilos ácido-álcool resistentes intralesionais e todos tiveram marcação positiva na técnica de imuno-histoquímica com anticorpo policlonal anti-Mycobacterium tuberculosis. Conclui-se que a tuberculose do sistema nervoso central de bovinos ocorre de forma esporádica na Paraíba, principalmente em bovinos com lesões disseminadas em outros órgãos. Sugere-se que a disseminação do agente ocorre pela via hematógena, possivelmente através do polígono de Willis.(AU)

Tuberculosis of the central nervous system in cattle in Paraíba, Brazil / Tuberculose no sistema nervoso central de bovinos na Paraíba

This paper describes six cases of tuberculosis in the central nervous system (CNS) of cattle in the state of Paraíba in northeastern Brazil. We reviewed the autopsy reports of 851 bovine necropsies performed from 2003 to 2016. Seventy-three (8.6%) cattle were diagnosed with tuberculosis and six showed lesions in the CNS. Three cases affected cattle up to two-year-old and other three affected adults. Three cattle presented exclusively nervous signs, two had respiratory signs and weight loss and one did not present any clinical signs. At necropsy, five cattle had thickening of the leptomeninges of the cerebellum, pons, obex, spinal cord and cortex, mainly, in the region near the brain basilar Willis´ circle. Another animal, presented a single focal lesion in the cerebellum. Microscopically we observed moderate to severe granulomatous meningitis and encephalitis. Five cattle presented lesions in the lungs and mediastinal lymph nodes and three of them had disseminated lesions in other organs. In all cattle acid-fast bacilli were observed in the lesions and marked positive for immunohistochemistry with polyclonal antibody anti-Mycobacterium tuberculosis. It is concluded that bovine tuberculosis of central nervous system occurs sporadically in Paraíba, in cattle of different ages, most of them with disseminate lesions in other organs. The location of the lesions suggests that the agent invaded the brain by hematogenous route through the circle of Willis.(AU)

Descrevem-se seis casos de tuberculose no sistema nervoso central (SNC) em bovinos, no semiárido da Paraíba. Foram revisados os laudos de um total de 851 necropsias de bovinos realizadas no período de 2003 a 2016. Destes, 73 (8,6%) foram diagnosticados com tuberculose e seis apresentavam lesões no SNC. Três casos ocorreram em bovinos de até dois anos de idade e três em bovinos adultos. Três bovinos apresentaram exclusivamente sinais nervosos, dois tinham sinais respiratórios e perda de peso e um não apresentava nenhum sinal clínico. Macroscopicamente, em cinco bovinos, havia espessamento das leptomeninges do cerebelo, medula espinhal, ponte, obex, colículos e córtex, principalmente, na região basilar encefálica próxima ao polígono de Willis. Em apenas um bovino houve a presença de tubérculo único no cerebelo. Microscopicamente observou-se moderada a acentuada meningite e encefalite granulomatosa. Cinco bovinos apresentaram lesões pulmonares e nos gânglios mediastínicos e três deles tinham lesões disseminadas em outros órgãos. Em todos os bovinos foram encontrados bacilos ácido-álcool resistentes intralesionais e todos tiveram marcação positiva na técnica de imuno-histoquímica com anticorpo policlonal anti-Mycobacterium tuberculosis. Conclui-se que a tuberculose do sistema nervoso central de bovinos ocorre de forma esporádica na Paraíba, principalmente em bovinos com lesões disseminadas em outros órgãos. Sugere-se que a disseminação do agente ocorre pela via hematógena, possivelmente através do polígono de Willis.(AU)

Tuberculose em felinos domésticos (Felis catus) no sul do Rio Grande do Sul / Tuberculosis in domestic cats (Felis catus) in southern Rio Grande do Sul

Descrevem-se os aspectos clínico patológicos de quatro casos de tuberculose em felinos domésticos no Sul do Rio Grande do sul. Foi realizado um estudo retrospectivo dos casos diagnosticados como tuberculose em gatos necropsiados no Laboratório Regional de Diagnóstico da Universidade Federal de Pelotas (LRD/UFPel) no período de janeiro de 2000 a dezembro de 2014. Em dois casos a amplificação da sequência genética IS6110 específica para Mycobacterium tuberculosis demonstrou que a doença era de origem humana. Os outros dois foram positivos para Mycobacterium spp. Os sinais clínicos caracterizaram-se por emagrecimento progressivo, anorexia e dispneia. As alterações macroscópicas evidenciadas eram de caquexia, aumento de volume dos linfonodos submandibulares com áreas focais de aspecto caseoso ao corte. Nos pulmões havia áreas multifocais a coalescentes amareladas de aspecto caseoso, discretamente elevadas e firmes na superfície pleural. Histologicamente havia broncopneumonia e linfadenite granulomatosas. A coloração de Ziehl-Neelsen evidenciou a presença de bacilos álcool-ácidos resistentes. Houve imunomarcação positiva para micobactéria pela técnica de imuno-histoquímica. Alerta-se para a importância da tuberculose felina como um problema de saúde pública pois gatos infectados podem servir de fonte para a disseminação das micobactérias no ambiente, além de serem sentinelas para a ocorrência da enfermidade em seres humanos.(AU)

Clinical pathological aspects of four cases of tuberculosis in domestic cats in southern Rio Grande do Sul is described. A retrospective study was conducted of cats diagnosed with tuberculosis and necropsied at the Regional Diagnostic Laboratory of the Federal University of Pelotas (LRD/UFPel) from January 2000 to December 2014. In two cases, the amplification of genetic sequence IS6110 specific to Mycobacterium tuberculosis demonstrated that the disease was of human origin. The other two were positive for Mycobacterium spp. The clinical signs were characterized by progressive weight loss, anorexia, and dyspnea. The evident macroscopic changes were cachexia, swelling of submandibular lymph nodes with focal areas of caseous aspect on cut surface. The lungs had multifocal caseous areas at the pleural surface. Histologically, the cats had pneumonia and granulomatous lymphadenitis. The Ziehl-Neelsen staining revealed the presence of alcohol-acid resistant bacteria. There was a positive immunostaining for mycobacteria by immunohistochemistry technique. We alert to the importance of feline tuberculosis as a public health problem, because infected cats may serve as source for dissemination of mycobacteria in the environment, and be sentinels for the occurrence of the disease in humans.(AU)

Tuberculose em felinos domésticos (Felis catus) no sul do Rio Grande do Sul / Tuberculosis in domestic cats (Felis catus) in southern Rio Grande do Sul

Descrevem-se os aspectos clínico patológicos de quatro casos de tuberculose em felinos domésticos no Sul do Rio Grande do sul. Foi realizado um estudo retrospectivo dos casos diagnosticados como tuberculose em gatos necropsiados no Laboratório Regional de Diagnóstico da Universidade Federal de Pelotas (LRD/UFPel) no período de janeiro de 2000 a dezembro de 2014. Em dois casos a amplificação da sequência genética IS6110 específica para Mycobacterium tuberculosis demonstrou que a doença era de origem humana. Os outros dois foram positivos para Mycobacterium spp. Os sinais clínicos caracterizaram-se por emagrecimento progressivo, anorexia e dispneia. As alterações macroscópicas evidenciadas eram de caquexia, aumento de volume dos linfonodos submandibulares com áreas focais de aspecto caseoso ao corte. Nos pulmões havia áreas multifocais a coalescentes amareladas de aspecto caseoso, discretamente elevadas e firmes na superfície pleural. Histologicamente havia broncopneumonia e linfadenite granulomatosas. A coloração de Ziehl-Neelsen evidenciou a presença de bacilos álcool-ácidos resistentes. Houve imunomarcação positiva para micobactéria pela técnica de imuno-histoquímica. Alerta-se para a importância da tuberculose felina como um problema de saúde pública pois gatos infectados podem servir de fonte para a disseminação das micobactérias no ambiente, além de serem sentinelas para a ocorrência da enfermidade em seres humanos.(AU)

Clinical pathological aspects of four cases of tuberculosis in domestic cats in southern Rio Grande do Sul is described. A retrospective study was conducted of cats diagnosed with tuberculosis and necropsied at the Regional Diagnostic Laboratory of the Federal University of Pelotas (LRD/UFPel) from January 2000 to December 2014. In two cases, the amplification of genetic sequence IS6110 specific to Mycobacterium tuberculosis demonstrated that the disease was of human origin. The other two were positive for Mycobacterium spp. The clinical signs were characterized by progressive weight loss, anorexia, and dyspnea. The evident macroscopic changes were cachexia, swelling of submandibular lymph nodes with focal areas of caseous aspect on cut surface. The lungs had multifocal caseous areas at the pleural surface. Histologically, the cats had pneumonia and granulomatous lymphadenitis. The Ziehl-Neelsen staining revealed the presence of alcohol-acid resistant bacteria. There was a positive immunostaining for mycobacteria by immunohistochemistry technique. We alert to the importance of feline tuberculosis as a public health problem, because infected cats may serve as source for dissemination of mycobacteria in the environment, and be sentinels for the occurrence of the disease in humans.(AU)

Detection of Mycobacterium avium subsp. paratuberculosis in bovine milk from the state of Pernambuco, Brazil

The aim of this study was to detect the IS900 region of Mycobacterium avium subsp. paratuberculosis (MAP) in bovine milk samples using real-time polymerase chain reaction (qPCR) and conventional PCR, and to study the agreement between these tests. A total of 121 bovine milk samples were collected from herds considered positive for MAP, from the State of Pernambuco, Brazil. MAP DNA was detected in 20 samples (16.5%) using conventional PCR and in 34 samples (28.1%) using qPCR. MAP DNA was detected in all of the 6 animal farms studied. Moderate agreement was found between qPCR and conventional PCR results, where the sensitivity and specificity of conventional PCR in relation to qPCR were 50% and 96.6%, respectively. Thus, the IS900 region of MAP was found in bovine milk samples from the State of Pernambuco. To the best of our knowledge, this is the first report of MAP DNA found in bovine milk in Northeast Brazil. We also demonstrated the qPCR technique is more sensitive than conventional PCR with respect to detection of MAP in milk samples.(AU)

Infection by Mycobacterium bovis in a dog from Brazil

Tuberculosis (TB) is a chronic disease caused by bacteria belonging to the Mycobacterium tuberculosis complex (MtbC). This disease rarely affects dogs. Canine infections are usually caused by M. tuberculosis. Mycobacterium bovis infections are rare in dogs and associated with consumption of raw milk or contaminated products. Here, we report a Boxer dog who had a M. bovis infection and was admitted to a Brazilian veterinary hospital with a presumptive diagnosis of chronic ehrlichiosis. Despite receiving treatment for chronic ehrlichiosis, it progressed to death. TB was diagnosed during post-mortem examinations using histopathological analysis. Ziehl-Neelsen staining revealed acid-fast bacilli in the kidneys, liver, mesentery, and a mass adhered to the liver. Further, PCR-restriction analysis was performed to identify mycobacteria in the samples. A restriction profile compatible with MtbC was found in the lungs. In addition, PCR-based MtbC typing deletions at different loci of chromosome 9 enabled the identification of M. bovis in the lungs. Therefore, it is very essential to perform differential diagnosis of TB in dogs with non-specific clinical signs and who do not respond to treatment, particularly those who had been in contact with TB-infected cattle or owners. Further, we highlight the use of molecular methods for the identification of bacilli, improving the diagnosis and aiding epidemiological studies.(AU)

Desempenho da cultura líquida MGIT após implementação em uma rede de laboratórios públicos do estado de São Paulo / Performance of liquid culture MGIT after implementation in a network of public laboratories of Sao Paulo state

A OMS, em 2007, recomendou a implementação da cultura líquida para o diagnóstico da tuberculose (TB) e teste de sensibilidade para países de baixa e média renda. Neste estudo foi avaliado o desempenho da cultura líquida MGIT em condição de rotina após dois anosde implantação em uma rede de laboratórios públicos. Foi efetuada análise retrospectiva de dados da cultura líquida, realizadas em dez laboratórios regionais do Instituto Adolfo Lutz, de janeiro a março de 2010. Foram incluídas amostras submetidas a baciloscopia, cultura líquida MGIT automatizada ou manual e identificação presuntiva do complexo Mycobacterium tuberculosis (CMTB). Foram detectadas 1.159 culturas positivas. Destas, 113 (9,7%) contaminaram, e 1.046 foram analisadas, sendo 850 (81,3%) CMTB, 116 (11,1%) micobactérias não tuberculosas e 6 (0,6%) Nocardia sp A taxa de contaminação foi de 2,2% e o acréscimo da cultura para o diagnóstico da TB foi de 29,9%. A média do tempo de detecção da cultura foi de 14,7 dias (DP+/- 11,7 dias). A acurácia da identificação presuntiva foi de 91,3%. A cultura líquida MGIT demonstrou ser excelente alternativa para efetuar diagnóstico da TB e das micobacterioses, em razão da rapidez possibilitando uma intervenção rápida e eficaz no tratamento.

In 2007, WHO recommended the implementation of liquid culture for tuberculosis (TB) diagnosis and drug-susceptibility test in low and middle-income countries. This study evaluated the performance of MGIT culture in routine condition after two years of its implementation in a public laboratories network.This is a retrospective study, which analyzed the data on the liquid culture performed in ten regional laboratories of the Institute Adolfo Lutz, from January to March 2010. The data included clinical samples submitted to microscopy, automated or manual MGIT culture and presumptive M. tuberculosis complex (MTBC) identification by analyzing the cord formation. Culture was positive in 1,159 samples. Of these, 113 (9.7%) contaminated, and 1,046 were analyzed, of which 850 (81.3%) were identified as MTBC, 116 (11.1%) as non-tuberculous mycobacteria and 6 (0.6%) as Nocardia sp. Contamination rate was 2.2% and the contribution of culture to the TB diagnosis was 29.9%. The detection mean time was 14.7 days (SD+/-11.7 days). The accuracy of the presumptive identification of MTBC was 91.3%. MGIT liquid culture demonstrated to be an excellent alternative for diagnosing TB and mycobacterioses, because of the rapidity of diagnosis, thus allowing an immediate and effective treatment.

Desempenho da cultura líquida MGIT após implementação em uma rede de laboratórios públicos do estado de São Paulo / Performance of liquid culture MGIT after implementation in a network of public laboratories of Sao Paulo state

A OMS, em 2007, recomendou a implementação da cultura líquida para o diagnóstico da tuberculose (TB) e teste de sensibilidade para países de baixa e média renda. Neste estudo foi avaliado o desempenho da cultura líquida MGIT em condição de rotina após dois anosde implantação em uma rede de laboratórios públicos. Foi efetuada análise retrospectiva de dados da cultura líquida, realizadas em dez laboratórios regionais do Instituto Adolfo Lutz, de janeiro a março de 2010. Foram incluídas amostras submetidas a baciloscopia, cultura líquida MGIT automatizada ou manual e identificação presuntiva do complexo Mycobacterium tuberculosis (CMTB). Foram detectadas 1.159 culturas positivas. Destas, 113 (9,7%) contaminaram, e 1.046 foram analisadas, sendo 850 (81,3%) CMTB, 116 (11,1%) micobactérias não tuberculosas e 6 (0,6%) Nocardia sp A taxa de contaminação foi de 2,2% e o acréscimo da cultura para o diagnóstico da TB foi de 29,9%. A média do tempo de detecção da cultura foi de 14,7 dias (DP+/- 11,7 dias). A acurácia da identificação presuntiva foi de 91,3%. A cultura líquida MGIT demonstrou ser excelente alternativa para efetuar diagnóstico da TB e das micobacterioses, em razão da rapidez possibilitando uma intervenção rápida e eficaz no tratamento.(AU)

In 2007, WHO recommended the implementation of liquid culture for tuberculosis (TB) diagnosis and drug-susceptibility test in low and middle-income countries. This study evaluated the performance of MGIT culture in routine condition after two years of its implementation in a public laboratories network.This is a retrospective study, which analyzed the data on the liquid culture performed in ten regional laboratories of the Institute Adolfo Lutz, from January to March 2010. The data included clinical samples submitted to microscopy, automated or manual MGIT culture and presumptive M. tuberculosis complex (MTBC) identification by analyzing the cord formation. Culture was positive in 1,159 samples. Of these, 113 (9.7%) contaminated, and 1,046 were analyzed, of which 850 (81.3%) were identified as MTBC, 116 (11.1%) as non-tuberculous mycobacteria and 6 (0.6%) as Nocardia sp. Contamination rate was 2.2% and the contribution of culture to the TB diagnosis was 29.9%. The detection mean time was 14.7 days (SD+/-11.7 days). The accuracy of the presumptive identification of MTBC was 91.3%. MGIT liquid culture demonstrated to be an excellent alternative for diagnosing TB and mycobacterioses, because of the rapidity of diagnosis, thus allowing an immediate and effective treatment.(AU)

Nasal swab real-time PCR is not suitable for in vivo diagnosis of bovine tuberculosis / A PCR em tempo real de swab nasal não é adequada para o diagnóstico in vivo de tuberculose bovina

Bovine tuberculosis (bTB) is a zoonosis causing economic losses and public health risks in many countries. The disease diagnosis in live animals is performed by intradermal tuberculin test, which is based on delayed hypersensitivity reactions. As tuberculosis has complex immune response, this test has limitations in sensitivity and specificity. This study sought to test an alternative approach for in vivo diagnosis of bovine tuberculosis, based on real-time polymerase chain reaction (PCR). DNA samples, extracted from nasal swabs of live cows, were used for SYBR® Green real-time PCR, which is able to differentiate between Mycobacterium tuberculosis and Mycobacterium avium complexes. Statistical analysis was performed to compare the results of tuberculin test, the in vivo gold standard bTB diagnosis method, with real-time PCR, thereby determining the specificity and sensitivity of molecular method. Cervical comparative test (CCT) was performed in 238 animals, of which 193 had suitable DNA from nasal swabs for molecular analysis, as indicated by amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, and were included in the study. In total, 25 (10.5%) of the animals were CCT reactive, of which none was positive in the molecular test. Of the 168 CCT negative animals, four were positive for M. tuberculosis complex at real time PCR from nasal swabs. The comparison of these results generated values of sensitivity and specificity of 0% and 97.6%, respectively; moreover, low coefficients of agreement and correlation (-0.029 and -0.049, respectively) between the results obtained with both tests were also observed. This study showed that real-time PCR from nasal swabs is not suitable for in vivo diagnosis of bovine tuberculosis; thus tuberculin skin test is still the best option for this purpose.(AU)

A tuberculose bovina (bTB) é uma zoonose que causa perdas econômicas e riscos à saúde pública em muitos países. O diagnóstico da doença em animais vivos é realizado pelo teste intradérmico da tuberculina, que é baseado em reações de hipersensibilidade tardia. Como a tuberculose tem resposta imunológica complexa, este teste tem limitações em termos de sensibilidade e especificidade. Este estudo procurou desenvolver uma abordagem alternativa para o diagnóstico in vivo da tuberculose bovina, com base na reação em cadeia da polimerase (PCR) em tempo real. As amostras de DNA, extraídas de suabes nasais de vacas vivas, foram usadas para PCR em tempo real com SYBR® Green, capaz de diferenciar os complexos Mycobacterium tuberculosis e Mycobacterium avium. A análise estatística foi realizada para comparar os resultados de teste de tuberculina, padrão ouro para o diagnóstico in vivo da bTB, com PCR em tempo real, determinando-se assim a especificidade e sensibilidade do método molecular. O teste cervical comparativo (TCC) foi realizado em 238 animais, dos quais 193 tiveram DNA dos suabes nasais adequados para análise molecular, como indicado pela amplificação do gene gliceraldeído-3-fosfato-desidrogenase (GAPDH), e foram incluídos no estudo. No total, 25 (10,5%) animais foram reativos no TCC, dos quais nenhum foi positivo no teste molecular. Dos 168 animais negativos no TCC, quatro foram positivos para o complexo M. tuberculosis na PCR em tempo real a partir dos suabes nasais. A comparação destes resultados gerou valores de sensibilidade e especificidade de 0% e 97,6%, respectivamente; além disso, baixos coeficientes de concordância e correlação (-0,029 e -0,049, respectivamente) entre os resultados obtidos com ambos os testes também foram observados. Este estudo mostrou que a PCR em tempo real a partir de suabes nasais não é adequada para o diagnóstico in vivo da tuberculose bovina; portanto, o teste da tuberculina ainda é a melhor opção para este fim.(AU)

Nasal swab real-time PCR is not suitable for in vivo diagnosis of bovine tuberculosis / A PCR em tempo real de swab nasal não é adequada para o diagnóstico in vivo de tuberculose bovina

Bovine tuberculosis (bTB) is a zoonosis causing economic losses and public health risks in many countries. The disease diagnosis in live animals is performed by intradermal tuberculin test, which is based on delayed hypersensitivity reactions. As tuberculosis has complex immune response, this test has limitations in sensitivity and specificity. This study sought to test an alternative approach for in vivo diagnosis of bovine tuberculosis, based on real-time polymerase chain reaction (PCR). DNA samples, extracted from nasal swabs of live cows, were used for SYBR® Green real-time PCR, which is able to differentiate between Mycobacterium tuberculosis and Mycobacterium avium complexes. Statistical analysis was performed to compare the results of tuberculin test, the in vivo gold standard bTB diagnosis method, with real-time PCR, thereby determining the specificity and sensitivity of molecular method. Cervical comparative test (CCT) was performed in 238 animals, of which 193 had suitable DNA from nasal swabs for molecular analysis, as indicated by amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, and were included in the study. In total, 25 (10.5%) of the animals were CCT reactive, of which none was positive in the molecular test. Of the 168 CCT negative animals, four were positive for M. tuberculosis complex at real time PCR from nasal swabs. The comparison of these results generated values of sensitivity and specificity of 0% and 97.6%, respectively; moreover, low coefficients of agreement and correlation (-0.029 and -0.049, respectively) between the results obtained with both tests were also observed. This study showed that real-time PCR from nasal swabs is not suitable for in vivo diagnosis of bovine tuberculosis; thus tuberculin skin test is still the best option for this purpose.(AU)

A tuberculose bovina (bTB) é uma zoonose que causa perdas econômicas e riscos à saúde pública em muitos países. O diagnóstico da doença em animais vivos é realizado pelo teste intradérmico da tuberculina, que é baseado em reações de hipersensibilidade tardia. Como a tuberculose tem resposta imunológica complexa, este teste tem limitações em termos de sensibilidade e especificidade. Este estudo procurou desenvolver uma abordagem alternativa para o diagnóstico in vivo da tuberculose bovina, com base na reação em cadeia da polimerase (PCR) em tempo real. As amostras de DNA, extraídas de suabes nasais de vacas vivas, foram usadas para PCR em tempo real com SYBR® Green, capaz de diferenciar os complexos Mycobacterium tuberculosis e Mycobacterium avium. A análise estatística foi realizada para comparar os resultados de teste de tuberculina, padrão ouro para o diagnóstico in vivo da bTB, com PCR em tempo real, determinando-se assim a especificidade e sensibilidade do método molecular. O teste cervical comparativo (TCC) foi realizado em 238 animais, dos quais 193 tiveram DNA dos suabes nasais adequados para análise molecular, como indicado pela amplificação do gene gliceraldeído-3-fosfato-desidrogenase (GAPDH), e foram incluídos no estudo. No total, 25 (10,5%) animais foram reativos no TCC, dos quais nenhum foi positivo no teste molecular. Dos 168 animais negativos no TCC, quatro foram positivos para o complexo M. tuberculosis na PCR em tempo real a partir dos suabes nasais. A comparação destes resultados gerou valores de sensibilidade e especificidade de 0% e 97,6%, respectivamente; além disso, baixos coeficientes de concordância e correlação (-0,029 e -0,049, respectivamente) entre os resultados obtidos com ambos os testes também foram observados. Este estudo mostrou que a PCR em tempo real a partir de suabes nasais não é adequada para o diagnóstico in vivo da tuberculose bovina; portanto, o teste da tuberculina ainda é a melhor opção para este fim.(AU)

Tuberculose pulmonar paucibacilar em Centros de Detenção Provisória / Paucibacillary pulmonary tuberculosis in Provisional Detention Centers

Cultura de micobactérias proporciona o crescimento de bacilos viáveis, mesmo presentes em escassa quantidade e não detectados pela baciloscopia. Neste estudo foram analisadas as amostras de escarro que apresentaram baciloscopia negativa e cultura positiva. As amostras foram coletadas de 2008 a 2013, de indivíduos detidos em Centros de Detenção Provisória de Santo André, Mauá e Diadema, Estado de São Paulo. As metodologias utilizadas foram baciloscopia por coloração Ziehl-Neelsen e cultura pelo Sistema BACTEC MGIT 960 e Ogawa-Kudoh. Dos 11.529 exames realizados, 221 (1,9 %) apresentaram baciloscopias negativas e culturas positivas. Dos 221 isolados, 166 (75,1 %) pertenciam ao Complexo Mycobacterium tuberculosis, 21 (9,5 %) micobactérias não membros do Complexo Mycobacterium tuberculosis (MNT), 33 (14,9 %) Mycobaterium sp e uma cultura mista do Complexo M. tuberculosis e M. avium. MNT mais frequentes foram M. avium (23,8 %) e M. fortuitum (19,0 %). A maioria dos isolados do Complexo M. tuberculosis (155/166 - 93,4 %) foi sensível aos antimicrobianos. Sete amostras apresentaram resistência à isoniazida e uma apresentou multirresistência à isoniazida e rifampicina. Este estudo mostra a importância da realização da cultura em escarros que apresentam baciloscopia negativa no diagnóstico da TB e micobacteriose. O tratamento tardio causa a continuidade da transmissão da doença e agravamento do quadro clínico.

Culture of mycobacteria induces the growth of viable bacillus occurring in small quantity, which are no detectable by bacilloscopy. This study aimed at identifying the mycobacteria isolates from sputum presenting negative bacilloscopy and positive culture. The samples were collected from 2008 to 2013 from criminals of Provisional Detention Centers in Santo André, Mauá and Diadema/SP. Smears were stained by Ziehl-Neelsen staining and the cultures were performed by the BACTEC MGIT 960 system and Ogawa-Kudoh culture medium. Of 11,529 isolates, 221 (1.9 %) showed negative bacilloscopy and positive cultures. Of 221 isolates, 166 (75.1 %) belonged to Mycobacterium tuberculosis complex, 21 (9.5 %) were nontuberculous mycobacteria (NTM), 33 (14.9 %) Mycobacterium sp, and one identified as a mixed culture of M. tuberculosis and M. avium complex. The most common NTM species were M. avium (23.8 %) and M. fortuitum (19.0 %). Most of the isolates (155/166-93.4 %) were susceptible to antimicrobial agents. Seven samples were resistant to isoniazid, and one presented multiresistance to isoniazid and rifampicin. This study shows the importance in performing sputum culture, when these samples are negative on bacilloscopy in diagnosing TB and mycobacteriosis. The treatment delay results in the maintenance of disease transmission and worsening of clinical symptoms.

Tuberculose pulmonar paucibacilar em Centros de Detenção Provisória / Paucibacillary pulmonary tuberculosis in Provisional Detention Centers

Cultura de micobactérias proporciona o crescimento de bacilos viáveis, mesmo presentes em escassa quantidade e não detectados pela baciloscopia. Neste estudo foram analisadas as amostras de escarro que apresentaram baciloscopia negativa e cultura positiva. As amostras foram coletadas de 2008 a 2013, de indivíduos detidos em Centros de Detenção Provisória de Santo André, Mauá e Diadema, Estado de São Paulo. As metodologias utilizadas foram baciloscopia por coloração Ziehl-Neelsen e cultura pelo Sistema BACTEC MGIT 960 e Ogawa-Kudoh. Dos 11.529 exames realizados, 221 (1,9 %) apresentaram baciloscopias negativas e culturas positivas. Dos 221 isolados, 166 (75,1 %) pertenciam ao Complexo Mycobacterium tuberculosis, 21 (9,5 %) micobactérias não membros do Complexo Mycobacterium tuberculosis (MNT), 33 (14,9 %) Mycobaterium sp e uma cultura mista do Complexo M. tuberculosis e M. avium. MNT mais frequentes foram M. avium (23,8 %) e M. fortuitum (19,0 %). A maioria dos isolados do Complexo M. tuberculosis (155/166 - 93,4 %) foi sensível aos antimicrobianos. Sete amostras apresentaram resistência à isoniazida e uma apresentou multirresistência à isoniazida e rifampicina. Este estudo mostra a importância da realização da cultura em escarros que apresentam baciloscopia negativa no diagnóstico da TB e micobacteriose. O tratamento tardio causa a continuidade da transmissão da doença e agravamento do quadro clínico.(AU)

Culture of mycobacteria induces the growth of viable bacillus occurring in small quantity, which are no detectable by bacilloscopy. This study aimed at identifying the mycobacteria isolates from sputum presenting negative bacilloscopy and positive culture. The samples were collected from 2008 to 2013 from criminals of Provisional Detention Centers in Santo André, Mauá and Diadema/SP. Smears were stained by Ziehl-Neelsen staining and the cultures were performed by the BACTEC MGIT 960 system and Ogawa-Kudoh culture medium. Of 11,529 isolates, 221 (1.9 %) showed negative bacilloscopy and positive cultures. Of 221 isolates, 166 (75.1 %) belonged to Mycobacterium tuberculosis complex, 21 (9.5 %) were nontuberculous mycobacteria (NTM), 33 (14.9 %) Mycobacterium sp, and one identified as a mixed culture of M. tuberculosis and M. avium complex. The most common NTM species were M. avium (23.8 %) and M. fortuitum (19.0 %). Most of the isolates (155/166-93.4 %) were susceptible to antimicrobial agents. Seven samples were resistant to isoniazid, and one presented multiresistance to isoniazid and rifampicin. This study shows the importance in performing sputum culture, when these samples are negative on bacilloscopy in diagnosing TB and mycobacteriosis. The treatment delay results in the maintenance of disease transmission and worsening of clinical symptoms.(AU)

Mycobacterium tuberculosis complex infection in Barbary sheep (Ammotragus lervia) at the Curitiba Zoo, southern Brazil: case report / Infecção pelo complexo Mycobacterium tuberculosis em carneiro da Barbária (Ammotragus lervia) no Zoológico de Curitiba, sul do Brasil: relato de caso

Tuberculosis is one of the most important mandatory notification diseases in the world caused by bacteria of the Mycobacterium tuberculosis complex, infecting both humans and animals. A sudden death of a Barbary sheep in Curitiba Zoo, and presence of multifocal nodules in lungs at necropsy raised suspicion of tuberculosis. Quantitative polymerase chain reaction (qPCR) from organs and fluid was performed and detected M. tuberculosis complex in a lung sample. This research reports the M. tuberculosis complex infection in Barbary sheep, a zoonosis of great relevance to public health and emphasizes the need to implement prevention measures. Furthermore, the research may provide a better understanding for species conservation, occurrence and transmission of diseases in captivity, reservoir potential and public health impact to zoo personnel and visitors.(AU)

A tuberculose é uma das doenças mundiais de notificação obrigatória mais importantes causada pelo complexo Mycobacterium tuberculosis que pode infectar pessoas e animais. A morte repentina de um carneiro da Barbária no Zoológico de Curitiba, que apresentou nódulos multifocais no pulmão à necropsia, levantou a suspeita de tuberculose. Foi realizada a Reação em Cadeia da Polimerase Quantitativa (qPCR) de fragmentos de órgãos e fluido. A qPCR detectou a presença do complexo M. tuberculosis nas amostras de pulmão. Este estudo relata a infecção pelo complexo M. tuberculosis no carneiro da Barbária, uma zoonose de grande relevância para a saúde pública, ressaltando-se a necessidade da implementação de medidas de prevenção. Além disso, pode prover um melhor entendimento sobre conservação de espécies, ocorrência e transmissão de doenças em cativeiro, potencial reservatório e impacto na saúde pública para visitantes e funcionários dos zoológicos.(AU)

Mycobacterium tuberculosis complex infection in Barbary sheep (Ammotragus lervia) at the Curitiba Zoo, southern Brazil: case report / Infecção pelo complexo Mycobacterium tuberculosis em carneiro da Barbária(Ammotragus lervia) no Zoológico de Curitiba, sul do Brasil: relato de caso

Tuberculosis is one of the most important mandatory notification diseases in the world caused by bacteria of the Mycobacterium tuberculosis complex, infecting both humans and animals. A sudden death of a Barbary sheep in Curitiba Zoo, and presence of multifocal nodules in lungs at necropsy raised suspicion of tuberculosis. Quantitative polymerase chain reaction (qPCR) from organs and fluid was performed and detected M. tuberculosis complex in a lung sample. This research reports the M. tuberculosis complex infection in Barbary sheep, a zoonosis of great relevance to public health and emphasizes the need to implement prevention measures. Furthermore, the research may provide a better understanding for species conservation, occurrence and transmission of diseases in captivity, reservoir potential and public health impact to zoo personnel and visitors.(AU)

A tuberculose é uma das doenças mundiais de notificação obrigatória mais importantes causada pelo complexo Mycobacterium tuberculosis que pode infectar pessoas e animais. A morte repentina de um carneiro da Barbária no Zoológico de Curitiba, que apresentou nódulos multifocais no pulmão à necropsia, levantou a suspeita de tuberculose. Foi realizada a Reação em Cadeia da Polimerase Quantitativa (qPCR) de fragmentos de órgãos e fluido. A qPCR detectou a presença do complexo M. tuberculosis nas amostras de pulmão. Este estudo relata a infecção pelo complexo M. tuberculosis no carneiro da Barbária, uma zoonose de grande relevância para a saúde pública, ressaltando-se a necessidade da implementação de medidas de prevenção. Além disso, pode prover um melhor entendimento sobre conservação de espécies, ocorrência e transmissão de doenças em cativeiro, potencial reservatório e impacto na saúde pública para visitantes e funcionários dos zoológicos.(AU)

Dormancy models for Mycobacterium tuberculosis: A minireview

Dormancy models for Mycobacterium tuberculosis play important roles in understanding various aspects of tuberculosis pathogenesis and in the testing of novel therapeutic regimens. By simulating the latent tuberculosis infection, in which the bacteria exist in a non-replicative state, the models demonstrate reduced susceptibility to antimycobacterial agents. This minireview outlines the models available for simulating latent tuberculosis both in vitro and in several animal species. Additionally, this minireview discusses the advantages and disadvantages of these models for investigating the bacterial subpopulations and susceptibilities to sterilization by various antituberculosis drugs..(AU)