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1.
J Infect Dev Ctries ; 17(10): 1373-1386, 2023 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-37956372

RESUMEN

INTRODUCTION: Mycobacterium tuberculosis genotyping has impacted evolutionary studies worldwide. Nonetheless, its application and the knowledge generated depend on the genetic marker evaluated and the detection technologies that have evolved over the years. Here we describe the timeline of main genotypic methods related to M. tuberculosis in Latin America and the main findings obtained. METHODOLOGY: Systematic searches through the PubMed database were performed from 1993 to May 2021. A total of 345 articles met the inclusion criteria and were selected. RESULTS: Spacer oligonucleotide typing (spoligotyping) was the most widely used method in Latin America, with decreasing use in parallel with increasing use of mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) and whole genome sequencing (WGS). Among the countries, Brazil, Mexico, and Argentina had the most publications, and a considerable part of the articles were in collaboration with Latin American or non-Latin American institutions; a small proportion of studies needed partnerships to perform the genotypic methods. The genotypic methods allowed the identification of M. tuberculosis genotypes with greater capacity for clonal expansion and revealed the predominance of the Euro-American lineage in Latin America. There was a notable presence of the Beijing family in Peru and Colombia. CONCLUSIONS: The data obtained demonstrated the importance of expanding collaborative networks of tuberculosis (TB) research groups to countries with low productivity in this area, the commitment of the few Latin American countries to advance TB research, as well as the inestimable value of building a Latin America database, considering ease of population mobility between countries.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , América Latina/epidemiología , Genotipo , Polimorfismo de Longitud del Fragmento de Restricción , Técnicas de Tipificación Bacteriana/métodos , Tuberculosis/epidemiología , Tuberculosis/microbiología , Mycobacterium tuberculosis/genética , Repeticiones de Minisatélite
2.
Tuberculosis (Edinb) ; 125: 102004, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33017720

RESUMEN

BACKGROUND: Since the implementation of the Xpert MTB/RIF in Sao Paulo, Brazil, numerous Mycobacterium tuberculosis isolates presenting "rifampicin-resistant genotype with rifampicin-susceptible phenotype" were observed. OBJECTIVE: To evaluate the prevalence, rpoB mutations and transmission of M. tuberculosis resistant to rifampicin on Xpert MTB/RIF but susceptible on BACTEC MGIT system, in Sao Paulo state. METHODS: Patients' isolates with this pattern of rifampicin discordance, collected from 2014 to 2017, had their rpoB predominant rifampicin-resistance-determining region sequenced and were genotyped by IS6110 restriction fragment-length polymorphism. FINDINGS: The prevalence of rifampicin-discordant M. tuberculosis with genotypic resistance was 55.1% (156/283). Among the sequenced and genotyped isolates, 75.5% (111/147) were in clusters, largely associated with the type of rpoB mutation. Most isolates (98.6%; 72/73) harbouring the predominant mutation, His445Asn, were pooled into the two largest clusters, SP2ga (42/72; 58.3%) and SP5o (12/72; 16.7%). Ranking second, isolates carrying the silent mutation Phe433Phe were mostly (92.3%; 24/26) gathered into four groups of the family SP25. CONCLUSION: These findings suggest that this unusual high rifampicin discrepancy proportion was greatly influenced by few actively circulating clusters. Further studies on many of the rpoB mutations identified in our setting are needed to elucidate their association with phenotypic rifampicin resistance.


Asunto(s)
Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana/genética , Epidemias/estadística & datos numéricos , Mutación , Mycobacterium tuberculosis/genética , Rifampin/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antituberculosos/farmacología , Brasil/epidemiología , Estudios Transversales , ARN Polimerasas Dirigidas por ADN/genética , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Fenotipo , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adulto Joven
3.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;49(2): 204-210, Mar.-Apr. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-782105

RESUMEN

Abstract: INTRODUCTION Characterization of Mycobacterium tuberculosis (MTB) isolates by DNA fingerprinting has contributed to tuberculosis (TB) control. The aim of this study was to determine the genetic diversity of MTB isolates from Tehran province in Iran. METHODS MTB isolates from 60 Iranian and 10 Afghan TB patients were fingerprinted by standard IS6110-restriction fragment length polymorphism (RFLP) analysis and spoligotyping. RESULTS The copy number of IS6110 ranged from 10-24 per isolate. The isolates were classified into 22 clusters showing ≥ 80% similarity by RFLP analysis. Fourteen multidrug-resistant (MDR) isolates were grouped into 4 IS6110-RFLP clusters, with 10 isolates [71% (95% CI: 45-89%)] in 1 cluster, suggesting a possible epidemiological linkage. Eighteen Iranian isolates showed ≥ 80% similarity with Afghan isolates. There were no strains with identical fingerprints. Spoligotyping of 70 isolates produced 23 distinct patterns. Sixty (85.7%) isolates were grouped into 13 clusters, while the remaining 10 isolates (14.2%) were not clustered. Ural (formerly Haarlem4) (n = 22, 31.4%) was the most common family followed by Central Asian strain (CAS) (n = 18, 25.7%) and T (n = 9, 12.8%) families. Only 1strain was characterized as having the Beijing genotype. Among 60 Iranian and 10 Afghan MTB isolates, 25% (95% CI: 16-37) and 70% (95% CI: 39-89) were categorized as Ural lineage, respectively. CONCLUSIONS A higher prevalence of Ural family MTB isolates among Afghan patients than among Iranian patients suggests the possible transmission of this lineage following the immigration of Afghans to Iran.


Asunto(s)
Humanos , Tuberculosis/microbiología , Variación Genética/genética , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana/métodos , Mycobacterium tuberculosis/genética , Polimorfismo de Longitud del Fragmento de Restricción , Análisis por Conglomerados , Dermatoglifia del ADN , Epidemiología Molecular , Genotipo , Irán , Mycobacterium tuberculosis/aislamiento & purificación
4.
Mem. Inst. Oswaldo Cruz ; 106(5): 524-535, Aug. 2011.
Artículo en Inglés | LILACS | ID: lil-597710

RESUMEN

The aim of the present study was to compare polymerase chain reaction (PCR)-based methods - spoligotyping and mycobacterial interspersed repetitive units (MIRU) typing - with the gold-standard IS6110 restriction fragment length polymorphism (RFLP) analysis in 101 isolates of Mycobacterium tuberculosis to determine the genetic diversity of M. tuberculosis clinical isolates from Delhi, North India. Spoligotyping resulted in 49 patterns (14 clusters); the largest cluster was composed of Spoligotype International Types (SITs)26 [Central-Asian (CAS)1-Delhi lineage], followed by SIT11 [East-African-Indian (EAI) 3-Indian lineage]. A large number of isolates (75 percent) belonged to genotypic lineages, such as CAS, EAI and Manu, with a high specificity for the Indian subcontinent, emphasising the complex diversity of the phylogenetically coherent M. tuberculosis in North India. MIRU typing, using 11 discriminatory loci, was able to distinguish between all but two strains based on individual patterns. IS6110-RFLP analysis (n = 80 strains) resulted in 67 unique isolates and four clusters containing 13 strains. MIRUs discriminated all 13 strains, whereas spoligotyping discriminated 11 strains. Our results validate the use of PCR-based molecular typing of M. tuberculosis using repetitive elements in Indian isolates and demonstrate the usefulness of MIRUs for discriminating low-IS6110-copy isolates, which accounted for more than one-fifth of the strains in the present study.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Adulto Joven , ADN Bacteriano , Variación Genética , Repeticiones de Minisatélite , Mycobacterium tuberculosis , Técnicas de Tipificación Bacteriana , Análisis por Conglomerados , Genotipo , India , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Secuencias Repetitivas de Ácidos Nucleicos
5.
Mem. Inst. Oswaldo Cruz ; 104(3): 441-443, May 2009. ilus, graf
Artículo en Inglés | LILACS | ID: lil-517008

RESUMEN

This is the first study describing the genetic polymorphism of Mycobacterium tuberculosis strains in the Indian Ocean Region. Using IS6110 RFLP analysis, 475 M. tuberculosis isolates from Madagascar, Comoros, Mauritius, Mozambique and La Reunion were compared. Of the 332 IS6110 profiles found, 43 were shared by clusters containing 2-65 strains. Six clusters were common to at least two countries. Of 52 families of strains with similar IS6110 profiles, 10 were common to at least two countries. Interestingly, another characteristic was the frequency (16.8 percent) of IS6110 single-copy strains. These strains could be distinguished using the DR marker. This preliminary evaluation suggests genetic similarity between the strains of the Indian Ocean Region. However, additional markers would be useful for epidemiological studies and to assess the ancient transmission of strains between countries of this region.


Asunto(s)
Mycobacterium tuberculosis/genética , Polimorfismo Genético/genética , Asia , Análisis por Conglomerados , Dermatoglifia del ADN , ADN Bacteriano/genética , Océano Índico , Polimorfismo de Longitud del Fragmento de Restricción
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