RESUMO
Isolates of the Mycobacterium chelonae-M. abscessus complex are subdivided into four clusters (CHI to CHIV) in the INNO-LiPA® Mycobacterium spp DNA strip assay. A considerable phenotypic variability was observed among isolates of the CHII cluster. In this study, we examined the diversity of 26 CHII cluster isolates by phenotypic analysis, drug susceptibility testing, whole genome sequencing and single-gene analysis. Pairwise genome comparisons were performed using several approaches, including average nucleotide identity (ANI) and genome-to-genome distance (GGD) among others. Based on ANI and GGD the isolates were identified as M. chelonae (14 isolates), M. franklinii (2 isolates) and M. salmoniphium (1 isolate). The remaining 9 isolates were subdivided into three novel putative genomospecies. Phenotypic analyses including drug susceptibility testing, as well as whole genome comparison by TETRA and delta differences, were not helpful in separating the groups revealed by ANI and GGD. The analysis of standard four conserved genomic regions showed that rpoB alone and the concatenated sequences clearly distinguished the taxonomic groups delimited by whole genome analyses. In conclusion, the CHII INNO-LiPa is not a homogeneous cluster; on the contrary, it is composed of closely related different species belonging to the M. chelonae-M. abscessus complex and also several unidentified isolates. The detection of these isolates, putatively novel species, indicates a wider inner variability than the presently known in this complex.
RESUMO
Isolates of the Mycobacterium chelonae-M. abscessus complex are subdivided into four clusters (CHI to CHIV) in the INNO-LiPA® Mycobacterium spp DNA strip assay. A considerable phenotypic variability was observed among isolates of the CHII cluster. In this study, we examined the diversity of 26 CHII cluster isolates by phenotypic analysis, drug susceptibility testing, whole genome sequencing and single-gene analysis. Pairwise genome comparisons were performed using several approaches, including average nucleotide identity (ANI) and genome-to-genome distance (GGD) among others. Based on ANI and GGD the isolates were identified as M. chelonae (14 isolates), M. franklinii (2 isolates) and M. salmoniphium (1 isolate). The remaining 9 isolates were subdivided into three novel putative genomospecies. Phenotypic analyses including drug susceptibility testing, as well as whole genome comparison by TETRA and delta differences, were not helpful in separating the groups revealed by ANI and GGD. The analysis of standard four conserved genomic regions showed that rpoB alone and the concatenated sequences clearly distinguished the taxonomic groups delimited by whole genome analyses. In conclusion, the CHII INNO-LiPa is not a homogeneous cluster; on the contrary, it is composed of closely related different species belonging to the M. chelonae-M. abscessus complex and also several unidentified isolates. The detection of these isolates, putatively novel species, indicates a wider inner variability than the presently known in this complex. (AU)
Assuntos
Classificação , Mycobacterium chelonae , Mycobacterium abscessus , Sequenciamento Completo do GenomaRESUMO
We report Buruli ulcer in a man in the Netherlands. Phenotyping of samples indicate the Buruli pathogen was acquired in Suriname and activated by trauma on return to the Netherlands. Awareness of this disease by clinicians in non-Buruli ulcer-endemic areas is critical for identification.
Assuntos
Úlcera de Buruli/diagnóstico , Úlcera de Buruli/microbiologia , Mycobacterium ulcerans/isolamento & purificação , Viagem , Idoso , Úlcera de Buruli/tratamento farmacológico , Humanos , Masculino , Países Baixos , SurinameRESUMO
Bovine tuberculosis (BTB) is a chronic and contagious disease that affects domestic animals, wildlife, and humans. Caused by Mycobacterium bovis, BTB causes major economic losses and poses a serious constraint to international livestock trade. Moreover, in developing countries where BTB controls are lacking, M. bovis is a public health concern. In most developing countries, the prevalence of BTB in livestock is unknown because the information is either not reported or not available. In Ecuador, there is no national BTB control program. This article reviews the BTB situation in Ecuador by examining exhaustive data from tuberculin testing surveys and slaughterhouse surveillance studies conducted in 1972-2008 in a variety of the country's geographic areas. In Ecuador, several factors, including the dairy industry's expansion (preempted by the high demand for milk and its by-products), intensified efforts to increase the cattle population, the presence of M. bovis, and a lack of BTB controls, have caused a rise in BTB prevalence, and consequently, a growing push for the implementation of a national BTB control program.
Assuntos
Tuberculose Bovina/epidemiologia , Animais , Bovinos , Equador/epidemiologia , Teste Tuberculínico , Zoonoses/epidemiologiaRESUMO
Bovine tuberculosis (BTB) is a chronic and contagious disease that affects domestic animals, wildlife, and humans. Caused by Mycobacterium bovis, BTB causes major economic losses and poses a serious constraint to international livestock trade. Moreover, in developing countries where BTB controls are lacking, M. bovis is a public health concern. In most developing countries, the prevalence of BTB in livestock is unknown because the information is either not reported or not available. In Ecuador, there is no national BTB control program. This article reviews the BTB situation in Ecuador by examining exhaustive data from tuberculin testing surveys and slaughterhouse surveillance studies conducted in 1972-2008 in a variety of the country's geographic areas. In Ecuador, several factors, including the dairy industry's expansion (preempted by the high demand for milk and its by-products), intensified efforts to increase the cattle population, the presence of M. bovis, and a lack of BTB controls, have caused a rise in BTB prevalence, and consequently, a growing push for the implementation of a national BTB control program.
La tuberculosis bovina es una enfermedad contagiosa crónica que afecta a los animales domésticos, los animales salvajes y los seres humanos. Es producida por Mycobacterium bovis; causa grandes pérdidas económicas y plantea una grave limitación para el comercio ganadero internacional. Por otro lado, en los países en desarrollo donde no hay controles de la tuberculosis bovina, la infección por M. bovis representa un problema de salud pública. En la mayoría de los países en desarrollo, la prevalencia de tuberculosis en el ganado se desconoce porque la información no se comunica o no se consigue. En el Ecuador no hay un programa nacional de control de la tuberculosis bovina. En este artículo se revisa la situación de la tuberculosis bovina en el Ecuador, sobre la base de un análisis de los datos exhaustivos obtenidos de encuestas sobre pruebas de tuberculina y de los estudios de vigilancia llevados a cabo en mataderos entre 1972 y 2008 en varias zonas geográficas del país. En el Ecuador varios factores, como el crecimiento de la industria láctea (impulsado por la alta demanda de leche y sus derivados), los intensos esfuerzos para aumentar la población bovina, la presencia de M. bovis y la falta de controles de la tuberculosis bovina, han ocasionado un aumento de la prevalencia de esta y, en consecuencia, representan una motivación creciente para llevar a cabo un programa nacional de control de la tuberculosis bovina.
Assuntos
Animais , Bovinos , Tuberculose Bovina/epidemiologia , Equador/epidemiologia , Teste Tuberculínico , Zoonoses/epidemiologiaRESUMO
Veterinary inspection in slaughterhouses allows for the detection of macroscopic lesions reminiscent of bovine tuberculosis, but the presence of Mycobacterium bovis must be confirmed by laboratory methods. This study aimed at comparing the performances of the standard diagnostic tools used to identify M. bovis in tissue specimens sampled from suspicious animals. During a two years period, 1390 cattle were inspected at the Machachi abattoir in the Mejia canton - Ecuador. A total of 33 animals with granulomatous lesions were detected, representing 2.33% (16/687) and 2.42% (17/703) animals examined in 2007 and 2008, respectively. Ninety-four tissue specimens were sampled and screened for the presence of mycobacteria. Acid-fast bacilli were identified in one third of the suspicious cattle (11/33) and suggestive microscopic lesions in 27.3% (9/33) of the samples examined by direct microscopy and histopathology, respectively. Culturing on Stonebrink medium and 16S-rRNA-based polymerase chain reaction (PCR) yielded 36.4% (12/33) and 27.3% (9/33) of positives, respectively. Compared to culture, other diagnostic procedures displayed a lower sensitivity, with 56.5% for PCR, and 43.5% for direct microscopy and histopathology; however, the specificity was higher (94.4% for PCR and microscopy, and 97.2% for histopathology). We conclude that reliable post-mortem laboratory testing either requires the combination of a set of available diagnostic tools or necessitates the development of improved new-generation tools with better sensitivity and specificity characteristics.
Assuntos
Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/diagnóstico , Matadouros , Animais , Autopsia/veterinária , Bovinos , Equador/epidemiologia , Pulmão/microbiologia , Reação em Cadeia da Polimerase/veterinária , Tuberculose Bovina/epidemiologiaRESUMO
We standardized a method to evaluate the growth kinetics of Mycobacterium tuberculosis by measuring quantitatively the reduction of resazurin by spectrophotometry. Growth curves and the rate of growth of twenty-one M. tuberculosis clinical isolates were determined. The method showed technical simplicity and is inexpensive to assess the fitness of each isolate.
Assuntos
Humanos , Infecções por Mycobacterium , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Corantes de Rosanilina , Técnicas e Procedimentos Diagnósticos , Cinética , Métodos , EspectrofotometriaRESUMO
RD(Rio) is a novel Mycobacterium tuberculosis lineage of the Latin American-Mediterranean (LAM) family. LAM has been found worldwide but is more predominant in South America. The aim of this study was to assess the presence of the RD(Rio) lineage and LAM family in the city of Rio Grande, Brazil, and to investigate the fitness of these strains based on determination of their growth rate. Fifty clinical isolates of M. tuberculosis were genotyped and 43 different patterns were found by spoligotyping and mycobacterial interspersed repetitive units-variable number of tandem repeats. The predominant genotypes belonged to the LAM family (54% of the strains) followed by clade T (22%) and Haarlem (16%). The RD(Rio) lineage represented 38% of the total strains and 70.4% of the LAM strains found in this study. Strains belonging to the LAM family showed a fitness advantage when comparing their rate of growth with that of non-LAM strains, but a significant difference between RD(Rio) and non-RD(Rio) strains was not confirmed.
Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar/microbiologia , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Meios de Cultura , Feminino , Aptidão Genética , Genótipo , Humanos , Lactente , Recém-Nascido , América Latina , Masculino , Região do Mediterrâneo , Pessoa de Meia-Idade , Repetições Minissatélites/genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Oligonucleotídeos/análise , Tuberculose Pulmonar/epidemiologia , Adulto JovemRESUMO
We standardized a method to evaluate the growth kinetics of Mycobacterium tuberculosis by measuring quantitatively the reduction of resazurin by spectrophotometry. Growth curves and the rate of growth of twenty-one M. tuberculosis clinical isolates were determined. The method showed technical simplicity and is inexpensive to assess the fitness of each isolate.