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1.
Curr Microbiol ; 81(6): 165, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714565

RESUMO

Legionella pneumophila (Lp) is a Gram-negative bacterium found in natural and artificial aquatic environments and inhalation of contaminated aerosols can cause severe pneumonia known as Legionnaires' Disease (LD). In Brazil there is hardly any information about this pathogen, so we studied the genetic variation of forty Legionella spp. isolates obtained from hotels, malls, laboratories, retail centers, and companies after culturing in BCYE medium. These isolates were collected from various sources in nine Brazilian states. Molecular identification of the samples was carried out using Sequence-Based Typing (SBT), which consists of sequencing and analysis of seven genes (flaA, pilE, asd, mip, mompS, proA, and neuA) to define a Sequence Type (ST). Eleven STs were identified among 34/40 isolates, of which eight have been previously described (ST1, ST80, ST152, ST242, ST664, ST1185, ST1464, ST1642) and three were new STs (ST2960, ST2962, and ST2963), the former identified in five different cooling towers in the city of São Paulo. The ST1 that is widely distributed in many countries was also the most prevalent in this study. In addition, other STs that we observed have also been associated with legionellosis in other countries, reinforcing the potential of these isolates to cause LD in Brazil. Unfortunately, no human isolates could be characterized until presently, but our observations strongly suggest the need of surveillance implementation system and control measures of Legionella spp. in Brazil, including the use of more sensitive genotyping procedures besides ST.


Assuntos
Variação Genética , Legionella pneumophila , Microbiologia da Água , Brasil , Legionella pneumophila/genética , Legionella pneumophila/isolamento & purificação , Legionella pneumophila/classificação , Humanos , Filogenia , Genótipo
2.
Mem Inst Oswaldo Cruz ; 116: e200517, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729319

RESUMO

Molecular-typing can help in unraveling epidemiological scenarios and improvement for disease control strategies. A literature review of Mycobacterium tuberculosis transmission in Brazil through genotyping on 56 studies published from 1996-2019 was performed. The clustering rate for mycobacterial interspersed repetitive units - variable tandem repeats (MIRU-VNTR) of 1,613 isolates were: 73%, 33% and 28% based on 12, 15 and 24-loci, respectively; while for RFLP-IS6110 were: 84% among prison population in Rio de Janeiro, 69% among multidrug-resistant isolates in Rio Grande do Sul, and 56.2% in general population in São Paulo. These findings could improve tuberculosis (TB) surveillance and set up a solid basis to build a database of Mycobacterium genomes.


Assuntos
Repetições Minissatélites/genética , Mycobacterium tuberculosis/genética , Polimorfismo de Fragmento de Restrição/genética , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Genótipo , Humanos , Epidemiologia Molecular , Mycobacterium tuberculosis/isolamento & purificação , Sequenciamento Completo do Genoma
3.
BMC Microbiol ; 19(1): 131, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195979

RESUMO

BACKGROUND: The Latin American & Mediterranean (LAM) spoligotype family is one of the most successful genotype of Mycobacterium tuberculosis worldwide and particularly prevalent in South-America. Within this family, a sublineage named Region of Difference Rio (RDRio) was reported initially in Brazil and is characterized by a genomic deletion of about 26.3 kb. This lineage seems to show a specific adaptation to the Euro-Latin American population. In this context, we sought to evaluate the LAM family and the presence of the RDRio genotype in samples from three Latin American countries including Paraguay, Venezuela and Argentina. To detect LAM strains reliably we applied a typing scheme using spoligotyping, 12 loci MIRU-VNTR, the Ag85C103 SNP and the regions of difference RDRio and RD174. IS6110-RFLP results were also used when available. RESULTS: Genotyping of 413 M. tuberculosis isolates from three Latin-American countries detected LAM (46%) and the ill-defined T clade (16%) as the most frequent families. The highest clustering rate was detected in the sample population from the city of Caracas in Venezuela. We observed considerable differences in the presence of the RDRio lineage, with high frequency in Caracas-Venezuela (55%) and low frequency in Buenos Aires-Argentina (11%) and Paraguay (10%). The molecular markers (RD174, Ag85C103, MIRU02-MIRU40 signature) of the RDRio lineage were essentially confirmed. For the LAM family, the most polymorphic loci were MIRU40, MIRU31, MIRU10, MIRU26, MIRU16 and the least polymorphic MIRU24, MIRU20, MIRU04, MIRU23. CONCLUSIONS: Our results suggest a differential adaptation of LAM-sublineages in neighboring populations and that RDRio strains spread regionally with different rates of distribution. The Ag85C SNP and RDs (RD174, RDRio) tested in this study can in fact facilitate molecular epidemiological studies of LAM strains in endemic settings and low-income countries.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Mycobacterium tuberculosis/classificação , Tuberculose/microbiologia , Adaptação Fisiológica , Argentina/epidemiologia , Análise por Conglomerados , Técnicas de Genotipagem , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Paraguai/epidemiologia , Filogeografia , Polimorfismo de Fragmento de Restrição , Venezuela/epidemiologia
4.
BMC Infect Dis ; 19(1): 1047, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823734

RESUMO

BACKGROUND: Molecular tests can allow the rapid detection of tuberculosis (TB) and multidrug-resistant TB (MDR-TB). TB-SPRINT 59-Plex Beamedex® is a microbead-based assay developed for the simultaneous spoligotyping and detection of MDR-TB. The accuracy and cost evaluation of new assays and technologies are of great importance for their routine use in clinics and in research laboratories. The aim of this study was to evaluate the performance of TB-SPRINT at three laboratory research centers in Brazil and calculate its mean cost (MC) and activity-based costing (ABC). METHODS: TB-SPRINT data were compared with the phenotypic and genotypic profiles obtained using Bactec™ MGIT™ 960 system and Genotype® MTBDRplus, respectively. RESULTS: Compared with MGIT, the accuracies of TB-SPRINT for the detection of rifampicin and isoniazid resistance ranged from 81 to 92% and 91.3 to 93.9%, respectively. Compared with MTBDRplus, the accuracies of TB-SPRINT for rifampicin and isoniazid were 99 and 94.2%, respectively. Moreover, the MC and ABC of TB-SPRINT were USD 127.78 and USD 109.94, respectively. CONCLUSION: TB-SPRINT showed good results for isoniazid and rifampicin resistance detection, but still needs improvement to achieve In Vitro Diagnostics standards.


Assuntos
Farmacorresistência Bacteriana , Citometria de Fluxo/métodos , Mycobacterium tuberculosis/genética , Tuberculose/diagnóstico , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Catalase/genética , Custos e Análise de Custo , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Citometria de Fluxo/economia , Genótipo , Humanos , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Regiões Promotoras Genéticas , Kit de Reagentes para Diagnóstico , Rifampina , Sensibilidade e Especificidade , Tuberculose/economia
5.
Mem Inst Oswaldo Cruz ; 112(3): 182-187, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28225901

RESUMO

BACKGROUND: Tuberculosis (TB) continues to be a disease that affects many countries around the world, including Brazil. Recently, a subtype of Latin American-Mediterranean family strain was identified and characterised by RDRio. The strain has been associated with different characteristics of the disease. OBJECTIVES: In the present study we investigated the association of epidemiological, clinical, radiological and bacteriological variables with pulmonary tuberculosis caused by RDRioMycobacterium tuberculosis strain in large regions of São Paulo. METHODS: We conducted a cross-sectional study in 530 patients with pulmonary tuberculosis, diagnosed using sputum culture, from two regions of the São Paulo state in Brazil. The samples were brought to São Paulo reference laboratories for epidemiological, clinical, radiological and bacteriological analyses, and the data were obtained from a TB notification system. RDRio genotyping and Spoligotyping of the samples were performed. For the analysis of the categorical variables we used the chi-square test or the Fisher's exact test, and for the continuous variables, the Mann-Whitney test. In addition, a logistic regression was used for multivariate analysis. Differences with p < 0.05 were considered significant. FINDINGS THE RDRIO: deletion was identified in 152 (28.7%) samples. In the univariate analysis, both the age groups above 25 years and alcohol consumption were associated with the RDRio deletion. The multivariate analysis confirmed the association of the RDRio deletion with the age groups: 25-35 years old [OR: 2.28 (1.02-5.07; p = 0.04)] and 36-60 years old (OR: 2.36 (1.11-5.05); p = 0.03], and also with alcohol consumption [OR: 1.63 (1.05-2.54); p = 0,03]. MAIN CONCLUSIONS: In this study, we identified new factors associated with the M. tuberculosis of the RDRio deletion strains infection.


Assuntos
Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/genética , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/microbiologia , Adulto , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Estudos Transversais , Genótipo , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Tuberculose Pulmonar/diagnóstico
6.
Mem Inst Oswaldo Cruz ; 112(11): 769-774, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29091137

RESUMO

BACKGROUND: The accurate detection of multidrug-resistant tuberculosis (MDR-TB) is critical for the application of appropriate patient treatment and prevention of transmission of drug-resistant Mycobacterium tuberculosis isolates. The goal of this study was to evaluate the correlation between phenotypic and molecular techniques for drug-resistant tuberculosis diagnostics. Molecular techniques used were the line probe assay genotype MTBDRplus and the recently described tuberculosis-spoligo-rifampin-isoniazid typing (TB-SPRINT) bead-based assay. Conventional drug susceptibility testing (DST) was done on a BACTECTM MGIT 960 TB. METHOD: We studied 80 M. tuberculosis complex (MTC) clinical isolates from Minas Gerais state, of which conventional DST had classified 60 isolates as MDR and 20 as drug susceptible. FINDINGS: Among the 60 MDR-TB isolates with MGIT as a reference, sensitivity, specificity, accuracy, and kappa for rifampicin (RIF) resistance using TB-SPRINT and MTBDRplus, were 96.7% versus 93.3%, 100.0% versus 100.0%, 97.5% versus 95.0% and 0.94 versus 0.88, respectively. Similarly, the sensitivity, specificity, accuracy, and kappa for isoniazid (INH) resistance were 85.0% and 83.3%, 100.0% and 100.0%, 88.8% and 87.5% and 0.74 and 0.71 for both tests, respectively. Finally, the sensitivity, specificity, accuracy, and kappa for MDR-TB were 85.0% and 83.3%, 100.0% and 100.0%, 88.8% and 87.5% and 0.74 and 0.71 for both tests, respectively. MAIN CONCLUSIONS: Both methods exhibited a good correlation with the conventional DST. We suggest estimating the cost-effectiveness of MTBDRplus and TB-SPRINT in Brazil.


Assuntos
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Brasil , Genótipo , Humanos , Técnicas de Diagnóstico Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
7.
BMC Infect Dis ; 15: 306, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26231661

RESUMO

BACKGROUND: We aimed to characterize the genetic diversity of drug-resistant Mycobacterium tuberculosis (MTb) clinical isolates and investigate the molecular epidemiology of multidrug-resistant (MDR) tuberculosis from Minas Gerais State, Brazil. METHODS: One hundred and four MTb clinical isolates were assessed by IS6110-RFLP, 24-locus mycobacterial interspersed repetitive units variable-number tandem repeats (MIRU-VNTR), TB-SPRINT (simultaneous spoligotyping and rifampicin-isoniazid drug-resistance mutation analysis) and 3R-SNP-typing (analysis of single-nucleotide polymorphisms in the genes involved in replication, recombination and repair functions). RESULTS: Fifty-seven different IS6110-RFLP patterns were found, among which 50 had unique patterns and 17 were grouped into seven clusters. The discriminatory index (Hunter and Gaston, HGDI) for RFLP was 0.9937. Ninety-nine different MIRU-VNTR patterns were found, 95 of which had unique patterns and nine isolates were grouped into four clusters. The major allelic diversity index in the MIRU-VNTR loci ranged from 0.6568 to 0.7789. The global HGDI for MIRU-VNTR was 0.9991. Thirty-two different spoligotyping profiles were found: 16 unique patterns (n = 16) and 16 clustered profiles (n = 88). The HGDI for spoligotyping was 0.9009. The spoligotyped clinical isolates were phylogenetically classified into Latin-American Mediterranean (66.34 %), T (14.42 %), Haarlem (5.76 %), X (1.92 %), S (1.92 %) and U (unknown profile; 8.65 %). Among the U isolates, 77.8 % were classified further by 3R-SNP-typing as 44.5 % Haarlem and 33.3 % LAM, while the 22.2 % remaining were not classified. Among the 104 clinical isolates, 86 were identified by TB-SPRINT as MDR, 12 were resistant to rifampicin only, one was resistant to isoniazid only, three were susceptible to both drugs, and two were not successfully amplified by PCR. A total of 42, 28 and eight isolates had mutations in rpoB positions 531, 526 and 516, respectively. Correlating the cluster analysis with the patient data did not suggest recent transmission of MDR-TB. CONCLUSIONS: Although our results do not suggest strong transmission of MDR-TB in Minas Gerais (using a classical 100 % MDR-TB identical isolates cluster definition), use of a smoother cluster definition (>85 % similarity) does not allow us to fully eliminate this possibility; hence, around 20-30 % of the isolates we analyzed might be MDR-TB transmission cases.


Assuntos
Variação Genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Alelos , Antituberculosos/uso terapêutico , Proteínas de Bactérias/genética , Brasil/epidemiologia , Análise por Conglomerados , DNA Bacteriano/análise , RNA Polimerases Dirigidas por DNA , Genótipo , Humanos , Isoniazida/uso terapêutico , Repetições Minissatélites/genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
8.
Mem Inst Oswaldo Cruz ; 110(2): 235-48, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25946248

RESUMO

Drug-resistant tuberculosis (TB) is a growing global threat. Approximately 450,000 people developed multidrug-resistant TB worldwide in 2012 and an estimated 170,000 people died from the disease. This paper describes the sociodemographic, clinical-epidemiological and bacteriological aspects of TB and correlates these features with the distribution of anti-TB drug resistance. Mycobacterium tuberculosis (MT) cultures and drug susceptibility testing were performed according to the BACTEC MGIT 960 method. The results demonstrated that MT strains from individuals who received treatment for TB and people who were infected with human immunodeficiency virus were more resistant to TB drugs compared to other individuals (p < 0.05). Approximately half of the individuals received supervised treatment, but most drug-resistant cases were positive for pulmonary TB and exhibited positive acid-fast bacilli smears, which are complicating factors for TB control programs. Primary healthcare is the ideal level for early disease detection, but tertiary healthcare is the most common entry point for patients into the system. These factors require special attention from healthcare managers and professionals to effectively control and monitor the spread of TB drug-resistant cases.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Tuberculose Resistente a Múltiplos Medicamentos/complicações , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia , Adulto Jovem
9.
Mem Inst Oswaldo Cruz ; 109(3): 307-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24821057

RESUMO

Drug-resistant tuberculosis (TB) threatens global TB control and is a major public health concern in several countries. We therefore developed a multiplex assay (LINE-TB/MDR) that is able to identify the most frequent mutations related to rifampicin (RMP) and isoniazid (INH) resistance. The assay is based on multiplex polymerase chain reaction, membrane hybridisation and colorimetric detection targeting of rpoB and katG genes, as well as the inhA promoter, which are all known to carry specific mutations associated with multidrug-resistant TB (MDR-TB). The assay was validated on a reference panel of 108 M. tuberculosis isolates that were characterised by the proportion method and by DNA sequencing of the targets. When comparing the performance of LINE-TB/MDR with DNA sequencing, the sensitivity, specificity and agreement were 100%, 100% and 100%, respectively, for RMP and 77.6%, 90.6% and 88.9%, respectively, for INH. Using drug sensibility testing as a reference standard, the performance of LINE-TB/MDR regarding sensitivity, specificity and agreement was 100%, 100% and 100% (95%), respectively, for RMP and 77%, 100% and 88.7% (82.2-95.1), respectively, for INH. LINE-TB/MDR was compared with GenoType MTBDRplus for 65 isolates, resulting in an agreement of 93.6% (86.7-97.5) for RIF and 87.4% (84.3-96.2) for INH. LINE-TB/MDR warrants further clinical validation and may be an affordable alternative for MDR-TB diagnosis.


Assuntos
Proteínas de Bactérias/genética , Catalase/genética , Farmacorresistência Bacteriana Múltipla/genética , Mutação/genética , Mycobacterium tuberculosis/genética , Oxirredutases/genética , Colorimetria , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA , Técnicas de Genotipagem , Isoniazida/farmacologia , Reação em Cadeia da Polimerase Multiplex , Mycobacterium tuberculosis/efeitos dos fármacos , Hibridização de Ácido Nucleico , Rifampina/farmacologia
10.
Mem Inst Oswaldo Cruz ; 108(4): 457-62, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23827995

RESUMO

The main cause of pulmonary tuberculosis (TB) is infection with Mycobacterium tuberculosis (MTB). We aimed to evaluate the contribution of nontuberculous mycobacteria (NTM) to pulmonary disease in patients from the state of Rondônia using respiratory samples and epidemiological data from TB cases. Mycobacterium isolates were identified using a combination of conventional tests, polymerase chain reaction-based restriction enzyme analysis of hsp65 gene and hsp65 gene sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded bacterial cultures, including 369 cases positive for MTB and 75 cases positive for NTM. Within the latter group, 14 species were identified as Mycobacterium abscessus, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium intracellulare, Mycobacterium gilvum, Mycobacterium gordonae, Mycobacterium asiaticum, Mycobacterium tusciae, Mycobacterium porcinum, Mycobacterium novocastrense, Mycobacterium simiae, Mycobacterium szulgai, Mycobacterium phlei and Mycobacterium holsaticum and 13 isolates could not be identified at the species level. The majority of NTM cases were observed in Porto Velho and the relative frequency of NTM compared with MTB was highest in Ji-Paraná. In approximately half of the TB subjects with NTM, a second sample containing NTM was obtained, confirming this as the disease-causing agent. The most frequently observed NTM species were M. abscessus and M. avium and because the former species is resistant to many antibiotics and displays unsatisfactory cure rates, the implementation of rapid identification of mycobacterium species is of considerable importance.


Assuntos
Micobactérias não Tuberculosas/classificação , Tuberculose Pulmonar/microbiologia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micobactérias não Tuberculosas/genética , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Escarro/microbiologia , Tuberculose Pulmonar/epidemiologia , Adulto Jovem
11.
Mem Inst Oswaldo Cruz ; 107(1): 64-73, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22310537

RESUMO

We performed spoligotyping and 12-mycobacterial interspersed repetitive unit-variable number tandem repeats (MIRU-VNTRs) typing to characterise Mycobacterium bovis isolates collected from tissue samples of bovines with lesions suggestive for tuberculosis during slaughter inspection procedures in abattoirs in Brazil. High-quality genotypes were obtained with both procedures for 61 isolates that were obtained from 185 bovine tissue samples and all of these isolates were identified as M. bovis by conventional identification procedures. On the basis of the spoligotyping, 53 isolates were grouped into nine clusters and the remaining eight isolates were unique types, resulting in 17 spoligotypes. The majority of the Brazilian M. bovis isolates displayed spoligotype patterns that have been previously observed in strains isolated from cattle in other countries. MIRU-VNTR typing produced 16 distinct genotypes, with 53 isolates forming eight of the groups, and individual isolates with unique VNTR profiles forming the remaining eight groups. The allelic diversity of each VNTR locus was calculated and only two of the 12-MIRU-VNTR loci presented scores with either a moderate (0.4, MIRU16) or high (0.6, MIRU26) discriminatory index (h). Both typing methods produced similar discriminatory indexes (spoligotyping h = 0.85; MIRU-VNTR h = 0.86) and the combination of the two methods increased the h value to 0.94, resulting in 29 distinct patterns. These results confirm that spoligotyping and VNTR analysis are valuable tools for studying the molecular epidemiology of M. bovis infections in Brazil.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Variação Genética/genética , Mycobacterium bovis/genética , Sequências de Repetição em Tandem/genética , Alelos , Animais , Bovinos , DNA Bacteriano/genética , Genótipo , Mycobacterium bovis/classificação , Mycobacterium bovis/isolamento & purificação
12.
Mem Inst Oswaldo Cruz ; 107 Suppl 1: 143-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23283465

RESUMO

We analysed 16 variable number tandem repeats (VNTR) and three single-nucleotide polymorphisms (SNP) in Mycobacterium leprae present on 115 Ziehl-Neelsen (Z-N)-stained slides and in 51 skin biopsy samples derived from leprosy patients from Ceará (n = 23), Pernambuco (n = 41), Rio de Janeiro (n = 22) and Rondônia (RO) (n = 78). All skin biopsies yielded SNP-based genotypes, while 48 of the samples (94.1%) yielded complete VNTR genotypes. We evaluated two procedures for extracting M. leprae DNA from Z-N-stained slides: the first including Chelex and the other combining proteinase and sodium dodecyl sulfate. Of the 76 samples processed using the first procedure, 30.2% were positive for 16 or 15 VNTRs, whereas of the 39 samples processed using the second procedure, 28.2% yielded genotypes defined by at least 10 VNTRs. Combined VNTR and SNP analysis revealed large variability in genotypes, but a high prevalence of SNP genotype 4 in the Northeast Region of Brazil. Our observation of two samples from RO with an identical genotype and seven groups with similar genotypes, including four derived from residents of the same state or region, suggest a tendency to form groups according to the origin of the isolates. This study demonstrates the existence of geographically related M. leprae genotypes and that Z-N-stained slides are an alternative source for M. leprae genotyping.


Assuntos
DNA Bacteriano/análise , Variação Genética , Hanseníase/microbiologia , Mycobacterium leprae/genética , Técnicas de Tipagem Bacteriana , Biópsia , Brasil , Genótipo , Humanos , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Coloração e Rotulagem
13.
Front Vet Sci ; 9: 1006090, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467663

RESUMO

The species Mycobacterium tuberculosis variant bovis (M. tuberculosis var. bovis) is associated with tuberculosis, mainly in cattle and buffaloes. This pathogen has the potential to infect other mammals, including humans. Tuberculosis caused by M. tuberculosis var. bovis is a zoonosis clinically identical to tuberculosis caused by Mycobacterium tuberculosis, and the recommended treatment in humans results in the use of antibiotics. In this study, we used the whole genome sequencing (WGS) methodology Illumina NovaSeq 6000 System platform to characterize the genome of M. tuberculosis var. bovis in cattle circulating in Mato Grosso, identify mutations related to drug resistance genes, compare with other strains of M. tuberculosis var. bovis brazilian and assess potential drug resistance. Four isolates of M. tuberculosis var. bovis of cattle origin representing the main livestock circuits, which had been more prevalent in previous studies in the state of Mato Grosso, were selected for the genomic study. The genome sizes of the sequenced strains ranged from 4,306,423 to 4,332,964 bp, and the GC content was 65.6%. The four strains from Mato Grosso presented resistance genes to pncA (pyrazinamide), characterized as drug-resistant strains. In addition to verifying several point mutations in the pncA, rpsA, rpsL, gid, rpoB, katG, gyrB, gyrA, tlyA, embA, embB, embC, fgd, fbiB, and fbiC genes, these genes were similar to antibiotic resistance in more than 92% of the Brazilian strains. Therefore, our results indicated a high genetic diversity between our isolates and other M. tuberculosis var. bovis isolated in Brazil. Thus, multiple transmission routes of this pathogen may be present in the production chain. So, to achieve a bovine tuberculosis-free health status, the use of the WGS as a control and monitoring tool will be crucial to determine these transmission routes.

14.
BMC Infect Dis ; 11: 110, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21527037

RESUMO

BACKGROUND: The classical spoligotyping technique, relying on membrane reverse line-blot hybridization of the spacers of the Mycobacterium tuberculosis CRISPR locus, is used world-wide (598 references in Pubmed on April 8th, 2011). However, until now no inter-laboratory quality control study had been undertaken to validate this technique. We analyzed the quality of membrane-based spoligotyping by comparing it to the recently introduced and highly robust microbead-based spoligotyping. Nine hundred and twenty-seven isolates were analyzed totaling 39,861 data points. Samples were received from 11 international laboratories with a worldwide distribution. METHODS: The high-throughput microbead-based Spoligotyping was performed on CTAB and thermolyzate DNA extracted from isolated Mycobacterium tuberculosis complex (MTC) strains coming from the genotyping participating centers. Information regarding how the classical Spoligotyping method was performed by center was available. Genotype discriminatory analyses were carried out by comparing the spoligotypes obtained by both methods. The non parametric U-Mann Whitney homogeneity test and the Spearman rank correlation test were performed to validate the observed results. RESULTS: Seven out of the 11 laboratories (63%), perfectly typed more than 90% of isolates, 3 scored between 80-90% and a single center was under 80% reaching 51% concordance only. However, this was mainly due to discordance in a single spacer, likely having a non-functional probe on the membrane used. The centers using thermolyzate DNA performed as well as centers using the more extended CTAB extraction procedure. Few centers shared the same problematic spacers and these problematic spacers were scattered over the whole CRISPR locus (Mostly spacers 15, 14, 18, 37, 39, 40). CONCLUSIONS: We confirm that classical spoligotyping is a robust method with generally a high reliability in most centers. The applied DNA extraction procedure (CTAB or thermolyzate) did not affect the results in this study. However performance was center-dependent, suggesting that training is a key component in quality assurance of spoligotyping. Overall, no particular spacer yielded a higher degree of deviating results, suggesting that errors occur randomly either in the process of re-using membranes, or during the reading of the results and transferring of data from the film to a digital file. Last, the performance of the microbead-based method was excellent as previously shown by Cowan et al. (J. Clin. Microbiol. 2004) and Zhang et al. (J. Med. Microbiol. 2009) and demonstrated the proper detection of spacer 15 that is known to occasionally give weak signals in the classical spoligotyping.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Tuberculose/microbiologia , Técnicas de Tipagem Bacteriana/instrumentação , Técnicas de Tipagem Bacteriana/normas , DNA Bacteriano/genética , Genótipo , Humanos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase/normas , Controle de Qualidade
15.
Mem Inst Oswaldo Cruz ; 106(2): 139-45, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21537671

RESUMO

We used a colorimetric reverse dot blot hybridization (CRDH) assay to detect the presence of mutations in a specific region of the rpoB gene, associated with rifampin (RIF) resistance, in a panel of 156 DNAs extracted from 103 RIF-sensitive and 53 RIF-resistant cultures of Mycobacterium tuberculosis. When compared with the antimicrobial susceptibility test (AST), the sensitivity and specificity of the CRDH were 92.3% and 98.1%, respectively. When compared with sequencing, the sensitivity and specificity of the CRDH were 90.6% and 100%, respectively. To evaluate the performance of the assay directly in clinical specimens, 30 samples from tuberculosis patients were used. For these samples, the results of the CRDH were 100% consistent with the results of the AST and sequencing. These results indicate that the rate of concordance of the CRDH is high when compared to conventional methods and sequencing data. The CRDH can be successfully applied when a rapid test is required for the identification of RIF resistance in M. tuberculosis.


Assuntos
Antibióticos Antituberculose/farmacologia , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Mutação/genética , Mycobacterium tuberculosis/genética , Rifampina/farmacologia , Southern Blotting , RNA Polimerases Dirigidas por DNA , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
16.
Front Vet Sci ; 8: 747226, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708105

RESUMO

Molecular diagnosis of bovine tuberculosis plays an essential role in the epidemiological knowledge of the disease. Bovine tuberculosis caused by Mycobacterium bovis represents a risk to human health. This study aimed to perform the genotypic characterization of M. bovis isolated from bovines diagnosed as tuberculosis from dairy herds in the state of Pernambuco, Brazil. Granulomas from 30 bovines were sent for microbiological culture, and colonies compatible with Mycobacterium spp. were obtained in at least one culture from 17/30 granulomas. All isolates were confirmed to be M. bovis by spoligotyping and 24loci MIRU-VNTR typing. While spoligotyping characterized the isolates as SB0121, SB0295, SB0852, SB0120, and an unclassified genotype, 24loci MIRU-VNTR rendered two clusters of two isolates each and 13 unique profiles. Loci ETR-A showed higher discriminatory power, and loci (ETR-B, ETR-C, MIRU16, MIRU27, and QUB26) showed moderate allelic diversity. This is the first study on the genetic variability of the infectious agent cause of bovine TB in Pernambuco and demonstrates variability of strains in the state. Thus, it corroborates the importance of this microorganism as agent of bovine tuberculosis and its zoonotic potential, this epidemiological tool being a determinant in the rigor of the sanitary practices of disease control in dairy herds.

17.
Front Vet Sci ; 8: 666283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981748

RESUMO

The molecular typing of Mycobacterium bovis, which causes bovine tuberculosis, can be accomplished by combining different polymorphic markers, contributing to its epidemiological investigation. Multispacer sequence typing (MST) is a sequencing-based method that employs intergenic regions susceptible to higher mutation rates given the low selection pressure. It has been applied to M. tuberculosis, but not to M. bovis. The aim of this study was to evaluate a MST for M. bovis. A total of 58 strains isolated from tissues with lesions suggestive of bovine tuberculosis, coming from cattle herds in six Brazilian states and four standard samples of M. bovis were typified employing the MST technique. Fourteen intergenic regions were used, and four types of genetic events were reported: single nucleotide mutation (SNP), insertion, deletion, and tandem repeat (TR). Seven loci were chosen for typing. Twenty-eight type sequences (ST) were identified, indicating type sequences (ST) were identified, indicating a 92.9% HGDI (Hunter Gaston Discriminatory Index). The data were used to analyze the evolutionary patterns of these isolates and correlate them to phylogeographic lineages based on the formation of clonal complexes generated from eBURST software. Later, we associated the MST with spoligotyping technique, currently considered the gold standard for classification of M. bovis. The results support the MST as an alternative method for genotyping of M. bovis. The method has the advantage of sequencing and the availability of sequences analyzed in public databases, which can be used by professionals around the world as a tool for further analysis. This was the first study to identify the variability of isolates of M. bovis by the MST method.

18.
Infect Genet Evol ; 77: 104044, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634644

RESUMO

Mycobacterium bovis is the main causative agent of bovine tuberculosis (bTB) being among the animal-adapted Mycobacterium tuberculosis complex. Herds can also be infected with non-tuberculous mycobacteria (NTM) causing a negative effect on the economy and on animal and human health through zoonotic infections. Molecular tools are required for mycobacteria identification; thus, it is laborious to determine the epidemiological information of mycobacteria among herds. We aimed to describe the mycobacterial pathogens associated with cases of suspected bTB lesions in cattle/buffaloes slaughtered for consumption and to investigate bTB transmission. We evaluated 74 lesion samples from 48 animals (27 bovine/21 buffaloes) from 16 mapped farms. Positives samples from nested-PCR were cultured in Lowenstein-Jensen (LJ), 2% pyruvate (LJ + P), and 2% glycerol (LJ + G) media, followed by Ziehl-Neelsen (ZN) staining technique and partial gene sequencing (hsp65, rpoB, and 16S-rRNA). Spoligotyping and 24-MIRU-VNTR were performed. The LJ + P increased the chance of obtaining bacilli. The respiratory tract and the oral cavity were the most important infection route. In addition, the calcified part of the lesions suggested chronic bTB. Spoligotypes of M. bovis (SIT986/SB0885) differed from others found in South America, and the MIRU-VNTR 24 loci suggested that bTB was associated to highly related strains. The NTM species found are of clinical importance in humans.


Assuntos
Tipagem Molecular/métodos , Infecções por Mycobacterium/veterinária , Mycobacterium/classificação , Zoonoses/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Brasil , Búfalos , Bovinos , Evolução Molecular , Microbiologia de Alimentos , Humanos , Epidemiologia Molecular , Boca/microbiologia , Mycobacterium/genética , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/microbiologia , Filogenia , Sistema Respiratório/microbiologia
19.
Infect Genet Evol ; 73: 337-341, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31170529

RESUMO

Lineage 1 (L1) is one of seven Mycobacterium tuberculosis complex (MTBC) lineages. The objective of this study was to improve the complex taxonomy of L1 using phylogenetic SNPs, and to look for the origin of the main L1 sublineage prevalent in Para, Brazil. We developed a high-throughput SNPs-typing assay based on 12-L1-specific SNPs. This assay allowed us to experimentally retrieve SNP patterns on nine of these twelve SNPs in 277 isolates previously tentatively assigned to L1 spoligotyping-based sublineages. Three collections were used: Pará-Brazil (71); RIVM, the Netherlands (102), Madagascar (104). One-hundred more results were generated in Silico using the PolyTB database. Based on the final SNPs combination, the samples were classified into 11 clusters (C1-C11). Most isolates within a SNP-based cluster shared a mutual spoligotyping-defined lineage. However, L1/EAI1-SOM (SIT48) and L1/EAI6-BGD1 (SIT591) showed a poor correlation with SNP data and are not monophyletic. L1/EAI8-MDG and L1/EAI3-IND belonged to C5; this result suggests that they share a common ancestor. L1.1.3/SIT129, a spoligotype pattern found in SNPs-cluster C6, was found to be shared between Pará/Brazil and Malawi. SIT129 was independently found to be highly prevalent in Mozambique, which suggests a migration history from East-Africa to Brazil during the 16th-18th slave trade period to Northern Brazil.


Assuntos
Variação Genética/genética , Mycobacterium tuberculosis/genética , População Negra/genética , Brasil , Genótipo , Humanos , Madagáscar , Moçambique , Países Baixos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Tuberculose/microbiologia
20.
Am J Trop Med Hyg ; 98(2): 372-375, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29210353

RESUMO

We conducted a population-based study of tuberculosis (TB) from 2009 to 2015 in an indigenous community of Brazil, the largest in the country, to investigate risk factors associated with recent TB transmission. The clinical isolates of Mycobacterium tuberculosis were genotyped by IS6110-RFLP (restriction fragment length polymorphism) and spoligotyping analysis. Among 67 isolates typed by RFLP, 69% fell into fifteen clusters, and 91% of TB cases with shared IS6110-RFLP pattern were diagnosed within 2 years of another case in the cluster. Individual risk factors associated with genetic clustering were domestic overcrowding (odds ratio [OR]: 6.10; 95% confidence interval [CI]: 1.50-24.88) and low social class (OR: 3.72; 95% CI: 1.00-13.98). Most reported contacts (76%) were identified within the household of the index TB case, but most of the genetic clustering of M. tuberculosis occurred outside of household (79%). Expanded contacts investigation and prophylaxis outside of household should be considered as a priority for TB control programs in this population.


Assuntos
Análise por Conglomerados , Grupos Populacionais/estatística & dados numéricos , Tuberculose/genética , Adulto , Brasil/epidemiologia , Brasil/etnologia , Busca de Comunicante , Características da Família/etnologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Análise Multivariada , Grupos Populacionais/etnologia , Fatores de Risco , Inquéritos e Questionários , Tuberculose/epidemiologia , Tuberculose/etnologia
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