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1.
J Infect Dev Ctries ; 14(8): 878-885, 2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32903232

RESUMEN

INTRODUCTION: Data about the genotypes of circulating Mycobacterium tuberculosis isolates (MTB) in Lebanon are scarce. This study was undertaken to reveal the spoligotypes of MTB isolates recovered from patients in Lebanon. METHODOLOGY: MTB isolates from 49 patients living in Lebanon were recovered and identified. The samples were heat killed and subjected to DNA extraction. Spoligotyping was performed using microbeads from TB-SPOL Kit and the fluorescence intensity was measured using Luminex 200®. Generated patterns were assigned to families using the SITVIT2 international database of the Pasteur Institute of Guadeloupe and compared. RESULTS: The spoligotyping of the 49 MTB isolates revealed that 31 isolates belonged to Lineage 4 (Euro-American, 63.3%), 12 to Lineage 3 (East- African Indian, 24.5%), 3 to Lineage 2 (East Asian, 6%) and 2 were unknown. Over half of the genotypes (16 of 30) harbored SIT127 supposed to belong to the L4.5 sublineage. One isolate belonging to the rare Manu-Ancestor SIT523 was recovered for the first time in Lebanon, being associated with highly virulent extensively drug-resistant (XDR) MTB phenotype. CONCLUSION: The application of the Spoligotyping Multiplex Luminex® method is an efficient, discriminatory and rapid method to use for first-lane genotyping of MTB isolates. Though humble numbers were tested, this study is one of the first to describe the genomic diversity and epidemiology of MTB isolates of Lebanon, and suggests an increasing prevalence of SIT127 in the country.

2.
Int J Infect Dis ; 95: 22-27, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32251801

RESUMEN

BACKGROUND: Patients with mixed-strain Mycobacterium tuberculosis infections may be at a high risk of poor treatment outcomes. However, the mechanisms through which mixed infections affect the clinical manifestations are not well recognized. Evidence suggests that failure to detect the pathogen diversity within the host can influence the clinical results. We aimed to investigate the effects of different genotypes in mixed infections and determine their relationship with heteroresistance in the treatment of Iranian tuberculosis patients. METHODS: One of the genotypes was identified in the culture and another genotype pattern in the mixed infection was predicted by comparing the pattern of MIRU-VNTR between the clinical specimens and their respective cultures in each patient. For all patients, the drug susceptibility testing was carried out on three single colonies from each clinical sample. The follow-up of patients was carried out during six months of treatment. RESULTS: Based on MIRU-VNTR profiles of clinical samples, we showed that 55.6% (25/45) of the Iranian patients included in the study had mixed infections. Patients with mixed infections had a higher rate of treatment failure, compared to others (P=0.03). By comparing clinical sample profiles to profiles obtained after culture, we were able to distinguish between major and hidden genotypes. Among hidden genotypes, Haarlem (L4.1.2) and Beijing (L2) were associated to treatment failure (6/8 patients). CONCLUSIONS: To conclude, we propose a procedure using the MIRU-VNTR method to identify the different genotypes in mixed infections. The present findings suggest that genotypes with potentially higher pathogenicity may not be detected when performing experimental culture in patients with mixed infections.


Asunto(s)
Coinfección/microbiología , Genotipo , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Adulto , Farmacorresistencia Bacteriana , Femenino , Técnicas de Genotipaje , Humanos , Irán , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Reacción en Cadena de la Polimerasa , Resultado del Tratamiento
3.
Tuberculosis (Edinb) ; 120: 101894, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32090855

RESUMEN

The most widely discussed antibiotic-resistant tuberculosis strains ("W" and "B0/W148", "CAO") belong to L2/Beijing Lineage and are characterized by IS6110 insertion sequences at the NTF locus. We present a high-throughput, microbead-based method, called NTF-RINT for detection of IS in NTF and Rifampicin and Isoniazid Typing. This method provides tuberculosis diagnostic confirmation, screens for the so-called modern L2/Beijing sublineage and detects mutations involved in resistance to Rifampicin (RIF) and Isoniazid (INH).

4.
BMC Infect Dis ; 19(1): 1047, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31823734

RESUMEN

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.


Asunto(s)
Farmacorresistencia Bacteriana , Citometría de Flujo/métodos , Mycobacterium tuberculosis/genética , Tuberculosis/diagnóstico , Antituberculosos/farmacología , Proteínas Bacterianas/genética , Catalasa/genética , Costos y Análisis de Costo , ARN Polimerasas Dirigidas por ADN/genética , Farmacorresistencia Bacteriana/efectos de los fármacos , Citometría de Flujo/economía , Genotipo , Humanos , Isoniazida/farmacología , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Regiones Promotoras Genéticas , Juego de Reactivos para Diagnóstico , Rifampin , Sensibilidad y Especificidad , Tuberculosis/economía
5.
Rev Soc Bras Med Trop ; 52: e20190257, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31778400

RESUMEN

INTRODUCTION: Mozambique is one of three countries with high prevalence of tuberculosis (TB), TB/human immunodeficiency virus coinfection, and multidrug-resistant TB. We aimed to describe Mycobacterium tuberculosis spoligotypes circulating among drug resistant (DR) strains from Beira, Mozambique comparing them with genotypes in the country. METHODS: We performed spoligotyping of 79 M. tuberculosis suspected of DR-TB compared all spoligotype patterns published on the international database and PubMed. RESULTS: Both in Beira and Mozambique (n=578), the main clades were Latin-American-Mediterranean, East-African-Indian, Beijing and T, with no extensively DR TB cases. CONCLUSIONS: Beira and Mozambique share the same population genetic structure of M. tuberculosis.


Asunto(s)
Variación Genética/genética , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Técnicas de Tipificación Bacteriana , Genotipo , Humanos , Mozambique , Mutación/genética , Filogenia
6.
Sci Rep ; 9(1): 15549, 2019 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-31664101

RESUMEN

Tuberculosis remains the world's leading cause of death from an infectious agent, and is a serious health problem in Papua New Guinea (PNG) with an estimated 36,000 new cases each year. This study describes the genetic diversity of Mycobacterium tuberculosis among tuberculosis patients in the Balimo/Bamu region in the Middle Fly District of Western Province in PNG, and investigates rifampicin resistance-associated mutations. Archived Ziehl-Neelsen-stained sputum smears were used to conduct microbead-based spoligotyping and assess genotypic resistance. Among the 162 samples included, 80 (49.4%) generated spoligotyping patterns (n = 23), belonging predominantly to the L2 Lineage (44%) and the L4 Lineage (30%). This is consistent with what has been found in other PNG regions geographically distant from Middle Fly District of Western Province, but is different from neighbouring South-East Asian countries. Rifampicin resistance was identified in 7.8% of the successfully sequenced samples, with all resistant samples belonging to the L2/Beijing Lineage. A high prevalence of mixed L2/L4 profiles was suggestive of polyclonal infection in the region, although this would need to be confirmed. The method described here could be a game-changer in resource-limited countries where large numbers of archived smear slides could be used for retrospective (and prospective) studies of M. tuberculosis genetic epidemiology.

7.
Infect Genet Evol ; 73: 337-341, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31170529

RESUMEN

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.


Asunto(s)
Variación Genética/genética , Mycobacterium tuberculosis/genética , Grupo de Ascendencia Continental Africana/genética , Brasil , Genotipo , Humanos , Madagascar , Mozambique , Países Bajos , Filogenia , Polimorfismo de Nucleótido Simple/genética , Tuberculosis/microbiología
8.
Emerg Infect Dis ; 25(3): 596-598, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30789333

RESUMEN

We performed a cross-border molecular epidemiology analysis of multidrug-resistant tuberculosis in Peru, Spain, and Italy. This analysis revealed frequent transmission in Peru and exportation of a strain that recreated similar levels of transmission in Europe during 2007-2017. Transnational efforts are needed to control transmission of multidrug-resistant tuberculosis globally.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Emigración e Inmigración , Europa (Continente)/epidemiología , Genoma Bacteriano , Genotipo , Humanos , Repeticiones de Minisatélite , Epidemiología Molecular , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Perú/epidemiología , Polimorfismo de Nucleótido Simple , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Secuenciación Completa del Genoma
9.
Biosens Bioelectron ; 128: 76-82, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30640123

RESUMEN

In this work, we achieved the selective detection of wild and mutated rpoB gene in M. tuberculosis using an electrochemical DNA (E-DNA) sensor based on polypyrrole/Fe3O4 nanocomposite bearing redox naphthoquinone tag on PAMAM (spaNQ/PAMAM/PPy/Fe3O4). The hybridization between a given probe and the complementary DNA target induced a large decrease in the naphthoquinone redox signal as measured by SWV and no cross-hybridization with single nucleotide mismatch DNA target occurred. Thanks to the catalytic properties of iron oxide nanoparticles combined with conducting properties of polypyrrole platform, we demonstrated that the transducing system allowed the detection of 1 fM of DNA target in a 50-µL drop corresponding to 3 × 104 copies of DNA. The sensor was able to detect the rpoB gene in PCR-amplified samples of genomic DNA and could also discriminate between the wild type rpoB gene and a single nucleotide mutated rpoB gene that provides resistance to rifampicin. Furthermore, the sensor could selectively detect the wild and mutant DNA in genomic samples without PCR amplification.


Asunto(s)
Proteínas Bacterianas/genética , Técnicas Biosensibles , ADN Bacteriano/aislamiento & purificación , ARN Polimerasas Dirigidas por ADN/genética , Mycobacterium tuberculosis/aislamiento & purificación , Proteínas Bacterianas/química , ADN Bacteriano/genética , ARN Polimerasas Dirigidas por ADN/química , Compuestos Férricos/química , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidad , Nanocompuestos/química , Polímeros/química , Pirroles/química
10.
Rev. Soc. Bras. Med. Trop ; 52: e20190257, 2019. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1057252

RESUMEN

Abstract INTRODUCTION Mozambique is one of three countries with high prevalence of tuberculosis (TB), TB/human immunodeficiency virus coinfection, and multidrug-resistant TB. We aimed to describe Mycobacterium tuberculosis spoligotypes circulating among drug resistant (DR) strains from Beira, Mozambique comparing them with genotypes in the country. METHODS: We performed spoligotyping of 79 M. tuberculosis suspected of DR-TB compared all spoligotype patterns published on the international database and PubMed. RESULTS: Both in Beira and Mozambique (n=578), the main clades were Latin-American-Mediterranean, East-African-Indian, Beijing and T, with no extensively DR TB cases. CONCLUSIONS: Beira and Mozambique share the same population genetic structure of M. tuberculosis.

11.
Infect Drug Resist ; 11: 1617-1625, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30319278

RESUMEN

Objective: Nigeria ranks fourth among the high tuberculosis (TB) burden countries. This study describes the prevalence of drug resistance and the genetic diversity of Mycobacterium tuberculosis in Abuja's Federal Capital Territory. Materials and methods: Two hundred and seventy-eight consecutive sputum samples were collected from adults with presumptive TB during 2013-2014. DNA was extracted from Löwenstein-Jensen cultures and analyzed for the identification of nontuberculous mycobacteria species, detection of drug resistance with line probe assays, and high-throughput spacer oligonucleotide typing (spoligotyping) using microbead-based hybridization. Results: Two hundred and two cultures were positive for M. tuberculosis complex, 24 negative, 38 contaminated, and 15 positive for nontuberculous mycobacteria. Five (2.5%) M. tuberculosis complex isolates were resistant to rifampicin (RIF) and isoniazid (multidrug resistant), nine (4.5%) to RIF alone, and 15 (7.4%) to isoniazid alone; two RIF-resistant isolates were also resistant to fluoroquinolones and ethambutol, and one multidrug resistant isolate was also resistant to ethambutol. Among the 180 isolates with spoligotyping results, 164 (91.1%) were classified as lineage 4 (Euro-American), 13 (7.2%) as lineage 5 (West African 1), two (1.1%) as lineage 2 (East Asia), and one (0.6%) as lineage 6 (West African 2). One hundred and fifty-six (86.7%) isolates were grouped in 17 clusters (2-108 isolates/cluster), of which 108 (60.0%) were grouped as L4.6.2/Cameroon (spoligotype international type 61). Conclusion: The description of drug resistance prevalence and genetic diversity of M. tuberculosis in this study may be useful for improving TB control in Nigeria.

12.
J Microbiol Methods ; 152: 10-17, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29913189

RESUMEN

Several diagnostic tests are being developed to detect drug resistance in tuberculosis. In line with previous developments detecting rifampicin and isoniazid resistance using microbead-based systems (spoligoriftyping and TB-SPRINT), we present here an assay called TB-EFI detecting mutations involved in resistance to ethambutol, fluoroquinolones and the three classical injectable drugs (kanamycin, amikacin and capreomycin) in Mycobacterium tuberculosis. The proposed test includes both wild-type and mutant probes for each targeted locus. Basic analysis can be performed manually. An upgraded interpretation is made available in Excel 2016®. Using a reference set of 61 DNA extracts, we show that TB-EFI provides perfect concordance with pyrosequencing. Concordance between genotypic resistance and phenotypic DST was relatively good (72 to 98% concordance), with lower efficiency for fluoroquinolones and ethambutol due to some untargeted mutations. When compared to phenotypical resistance, performances were similar to those obtained with Hain MTBDRsl assay, possibly thanks to the use of automatized processing of data although some mutations involved in fluoroquinolone resistance could not be included. When applied on three uncharacterized sets, phenotype could be predicted for 51% to 98% depending on the setting and the drug investigated, detecting one extensively drug-resistant isolate in each of a Pakistan and a Brazilian set of 91 samples, and 9 XDR among 43 multi-resistant Kazakhstan samples. By allowing high-throughput detection of second-line drugs resistance and of resistance to ethambutol that is often combined to second-line treatments, TB-EFI is a cost-effective assay for large-scale worldwide surveillance of resistant tuberculosis and XDR-TB control.


Asunto(s)
Antituberculosos/farmacología , Pruebas Diagnósticas de Rutina/métodos , Etambutol/farmacología , Microesferas , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Alelos , Antituberculosos/uso terapéutico , ADN Bacteriano/genética , Fluoroquinolonas/farmacología , Genotipo , Técnicas de Genotipaje , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Microfluídica/métodos , Mutación , Mycobacterium tuberculosis/genética , Pentosiltransferasa , Sensibilidad y Especificidad
14.
Sci Rep ; 8(1): 3987, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29507363

RESUMEN

The worldwide dissemination of Mycobacterium tuberculosis strains has led to the study of their genetic diversity. One of the most used genotyping methods is spoligotyping, based on the detection of spacers in the clustered regularly interspaced short palindromic repeats (CRISPR) locus. This study assessed the performance of a microbead-based spoligotyping assay using samples extracted from Ziehl-Neelsen-stained smear-microscopy preparations and described the genetic diversity of Mycobacterium tuberculosis among new TB patients in Southern Nations, Nationalities and Peoples' Region (SNNPR) in Ethiopia. Among the 91 samples analysed, 59 (64.8%) generated spoligotyping patterns. Fifty (84.7%) samples were classified into 12 clusters (mostly Lineage 4 or 3) comprising 2-11 samples and nine had unique spoligotyping patterns. Among the 59 spoligotyping patterns, 25 belonged to the T1 sublineage, 11 to the T3-ETH, 5 to the URAL, 4 to the H3 and 14 to other L4 sublineages. There was a remarkable variation in genetic distribution in SNNPR compared to other regions of the country. Microbead-based spoligotyping is an easy-to-perform, high-throughput assay that can generate genotyping information using material obtained from smear microscopy preparations. The method provides an opportunity to obtain data of the M. tuberculosis genetic epidemiology in settings with limited laboratory resources.


Asunto(s)
Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Adulto , Técnicas de Tipificación Bacteriana/métodos , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Etiopía/epidemiología , Variación Genética , Técnicas de Genotipaje/métodos , Humanos , Epidemiología Molecular , Tipificación Molecular/métodos , Mycobacterium tuberculosis/clasificación , Tuberculosis/epidemiología
15.
PLoS Negl Trop Dis ; 12(2): e0006242, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29447161

RESUMEN

METHODS: All State TB control programmes in Nigeria were requested to submit 25-50 smear-positive Ziehl-Neelsen (ZN) stained slides for screening during 2013-2014. DNA was extracted from 929 slides for spoligotyping and drug-resistance analysis using microbead-based flow-cytometry suspension arrays. RESULTS: Spoligotyping results were obtained for 549 (59.1%) of 929 samples. Lineage 4 Cameroon sublineage (L4.6.2) represented half of the patterns, Mycobacterium africanum (L5 and L6) represented one fifth of the patterns, and all other lineages, including other L4 sublineages, represented one third of the patterns. Sublineage L4.6.2 was mostly identified in the north of the country whereas L5 was mostly observed in the south and L6 was scattered. The spatial distribution of genotypes had genetic geographic gradients. We did not obtain results enabling the detection of drug-resistance mutations. CONCLUSION/SIGNIFICANCE: We present the first national snapshot of the M. tuberculosis spoligotypes circulating in Nigeria based on ZN slides. Spoligotyping data can be obtained in a rapid and high-throughput manner with DNA extracted from ZN-stained slides, which may potentially improve our understanding of the genetic epidemiology of TB.


Asunto(s)
ADN Bacteriano/genética , Tipificación Molecular/métodos , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Biología Computacional , ADN Bacteriano/aislamiento & purificación , Variación Genética , Genotipo , Humanos , Epidemiología Molecular , Tipificación Molecular/instrumentación , Mycobacterium tuberculosis/clasificación , Nigeria/epidemiología , Filogeografía , Esputo/microbiología , Coloración y Etiquetado , Tuberculosis/epidemiología
16.
Nat Genet ; 50(2): 307-316, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29358649

RESUMEN

To characterize the genetic determinants of resistance to antituberculosis drugs, we performed a genome-wide association study (GWAS) of 6,465 Mycobacterium tuberculosis clinical isolates from more than 30 countries. A GWAS approach within a mixed-regression framework was followed by a phylogenetics-based test for independent mutations. In addition to mutations in established and recently described resistance-associated genes, novel mutations were discovered for resistance to cycloserine, ethionamide and para-aminosalicylic acid. The capacity to detect mutations associated with resistance to ethionamide, pyrazinamide, capreomycin, cycloserine and para-aminosalicylic acid was enhanced by inclusion of insertions and deletions. Odds ratios for mutations within candidate genes were found to reflect levels of resistance. New epistatic relationships between candidate drug-resistance-associated genes were identified. Findings also suggest the involvement of efflux pumps (drrA and Rv2688c) in the emergence of resistance. This study will inform the design of new diagnostic tests and expedite the investigation of resistance and compensatory epistatic mechanisms.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Tuberculosis Extensivamente Resistente a Drogas/microbiología , Genoma Bacteriano , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Antituberculosos/uso terapéutico , ADN Bacteriano/análisis , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Variación Genética , Estudio de Asociación del Genoma Completo , Geografía , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
17.
Mem Inst Oswaldo Cruz ; 112(11): 769-774, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29091137

RESUMEN

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.


Asunto(s)
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Brasil , Genotipo , Humanos , Técnicas de Diagnóstico Molecular , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
18.
Mem. Inst. Oswaldo Cruz ; 112(11): 769-774, Nov. 2017. tab
Artículo en Inglés | LILACS | ID: biblio-894852

RESUMEN

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.


Asunto(s)
Humanos , Técnicas Bacteriológicas/métodos , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Mycobacterium tuberculosis/genética , Brasil , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Patología Molecular , Genotipo
19.
PLoS One ; 12(10): e0186088, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29053711

RESUMEN

BACKGROUND: Combining different molecular typing methods for Mycobacterium tuberculosis complex (MTBC) can be a powerful tool for molecular epidemiology-based investigation of TB. However, the current standard method that provides high discriminatory power for such a combination, mycobacterial interspersed repetitive units-variable numbers of tandem repeats typing (MIRU-VNTR), is laborious, time-consuming and often too costly for many resource-limited laboratories. We aimed to evaluate a reduced set of loci for MIRU-VNTR typing in combination with spoligotyping and SNP-typing for routine molecular epidemiology of TB. METHOD: Spoligotyping and SNP-typing, in combination with the 15 loci MIRU-VNTR typing, were first used to type clinical MTBC isolates (n = 158) from Madagascar. A step by step reduction of MIRU-VNTR loci number was then performed according to the Hunter and Gaston Discriminatory Index (HGDI) and to the Principal component analysis (PCA) correlation with the spoligotype profiles to evaluate the discrimination power inside the generated spoligotype clusters. The 15 MIRU-VNTR was used as reference and SNP-typing was used to determine the main MTBC lineages. RESULTS: Of the 158 clinical isolates studied, the SNP-typing classified 23 into Lineage 1 (14.6%), 31 into Lineage 2 (19.6%), 23 into Lineage 3 (14.6%) and 81 into Lineage 4 strains (51.3%). 37 different spoligotypes profiles were obtained, 15 of which were unique and 20 in clusters. 15-loci MIRU-VNTR typing revealed 144 different genotypes: 132 isolates had a unique MIRU-VNTR profile and 27 isolates were grouped into 12 clusters. After a stepwise reduction of the MIRU-VNTR loci number within each main spoligotype families, three different sets composed of 5 customised MIRU-VNTR loci had a similar discrimination level to the reference 15 loci MIRU-VNTR in lineage 1, lineage 2 and lineage 3. For lineage 4, a set of 4 and 3 MIRU-VNTR loci were proposed to subtype the Harleem and LAM spoligotype families, respectively. For the T spoligotype family, a set of 5 MIRU-VNTR loci was proposed. CONCLUSION: According to the lineages and the spoligotype families, the number of MIRU-VNTR loci can be reduced to get an optimal classification of MTBC. These customized sets of MIRU-VNTR loci reduce workload and save resources while maintaining optimal discriminatory power.


Asunto(s)
Genotipo , Repeticiones de Minisatélite , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleótido Simple , Madagascar
20.
Infect Genet Evol ; 56: 62-72, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29081357

RESUMEN

There is only scarce information available on genotypic diversity of the Mycobacterium tuberculosis complex (MTBC) clinical isolates circulating in the Northern part of Brazil, a relatively neglected region regarding research on tuberculosis. We therefore characterized 980 MTBC clinical isolates from the state of Pará, by spoligotyping and data was compared with patterns from around the world, besides analyzing drug susceptibility, and collecting sociodemographic data. We also performed 24 loci MIRU-VNTR typing to evaluate phylogenetic inferences among the East-African-Indian (EAI) lineage strains. The Geographic Information System analyses were performed to generate a descriptive visualization of MTBC strain distribution in the region. A total of 249 different spoligopatterns primarily belonging to evolutionary recent Euro-American lineages, as well as Central-Asian, Manu and ancestral EAI lineages, were identified, in addition to strains with reportedly unknown lineage signatures. The most frequent lineages were Latin American Mediterranean, T and Haarlem. Interestingly, EAI lineage strains were found in a significantly higher proportion in comparison with previous studies from South America. Regarding EAI lineage, the absence of spacers 4-9 and 23-24 co-related to 24 loci MIRU-VNTRs may suggest a close evolutionary relationship between such strains in Pará and those prevalent in Mozambique, which might have contributed to the genetic diversity of MTBC strains in this region.


Asunto(s)
Variación Genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/genética , Tuberculosis/epidemiología , Tuberculosis/microbiología , Adolescente , Adulto , Distribución por Edad , Brasil/epidemiología , Niño , Preescolar , ADN Bacteriano , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Repeticiones de Minisatélite , Tipificación Molecular , Filogenia , Filogeografía , Adulto Joven
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