RESUMEN
In order to identify the genetic characteristics of the strains of mycobacteria circulating in the Estado de México, one of the states with the lowest prevalence of tuberculosis in Mexico, spoligotyping and 12-loci MIRU-VNTR typing were used to genotype tuberculosis clinical isolates. The average age of the 183 patients analyzed was 50 (± 17) years, drug resistance was noted in 57 (31%) and multidrug resistance in 22 (12%) individuals. The results from the isolates recovered showed that 80% were located in four major Euro-American lineages: Haarlem (17%), LAM (15%), T (20%) and X (29%). Other lineages found in lower proportions were: EAI, S, Beijing, West African, Turkey, Vole and Bovis. Eighteen isolates were orphans. Only 57 isolates were grouped in nine clusters and the SIT119 (X1) showed the highest number of members (23). The LAM lineage showed an increased risk for development of drug resistance (RR=4, IC: 95%: 1.05-14.2, p = 0.03). Despite the important prevalence of four major lineages found and the diversity of strains circulating in the population, we found the presence of one of the largest populations of isolates clustered to the X lineage in a setting from a Latin American country.
Asunto(s)
Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/microbiología , ADN Bacteriano/genética , Farmacorresistencia Bacteriana Múltiple , Femenino , Variación Genética , Humanos , Masculino , México/epidemiología , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Tipificación Molecular , Mycobacterium bovis/clasificación , Mycobacterium bovis/aislamiento & purificación , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , PrevalenciaRESUMEN
Tuberculosis (TB) is an infectocontagious respiratory disease caused by members of the Mycobacterium tuberculosis complex. A 7 base pair (bp) deletion in the locus polyketide synthase (pks)15/1 is described as polymorphic among members of the M. tuberculosis complex, enabling the identification of Euro-American, Indo-Oceanic and Asian lineages. The aim of this study was to characterise this locus in TB isolates from Mexico. One hundred twenty clinical isolates were recovered from the states of Veracruz and Estado de Mexico. We determined the nucleotide sequence of a ± 400 bp fragment of the locus pks15/1, while genotypic characterisation was performed by spoligotyping. One hundred and fifty isolates contained the 7 bp deletion, while five had the wild type locus. Lineages X (22%), LAM (18%) and T (17%) were the most frequent; only three (2%) of the isolates were identified as Beijing and two (1%) EAI-Manila. The wild type pks15/1 locus was observed in all Asian lineage isolates tested. Our results confirm the utility of locus pks15/1 as a molecular marker for identifying Asian lineages of the M. tuberculosis complex. This marker could be of great value in the epidemiological surveillance of TB, especially in countries like Mexico, where the prevalence of such lineages is unknown.
Asunto(s)
Proteínas Bacterianas/genética , Genes Bacterianos/genética , Sitios Genéticos/genética , Mycobacterium tuberculosis/genética , Sintasas Poliquetidas/genética , Adulto , Secuencia de Bases , Farmacorresistencia Bacteriana Múltiple/genética , Monitoreo Epidemiológico , Femenino , Marcadores Genéticos/genética , Humanos , Masculino , México , Persona de Mediana Edad , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Eliminación de Secuencia , Esputo/microbiologíaRESUMEN
Tuberculosis (TB) is an infectocontagious respiratory disease caused by members of the Mycobacterium tuberculosis complex. A 7 base pair (bp) deletion in the locus polyketide synthase (pks)15/1 is described as polymorphic among members of the M. tuberculosis complex, enabling the identification of Euro-American, Indo-Oceanic and Asian lineages. The aim of this study was to characterise this locus in TB isolates from Mexico. One hundred twenty clinical isolates were recovered from the states of Veracruz and Estado de Mexico. We determined the nucleotide sequence of a ± 400 bp fragment of the locus pks15/1, while genotypic characterisation was performed by spoligotyping. One hundred and fifty isolates contained the 7 bp deletion, while five had the wild type locus. Lineages X (22%), LAM (18%) and T (17%) were the most frequent; only three (2%) of the isolates were identified as Beijing and two (1%) EAI-Manila. The wild type pks15/1 locus was observed in all Asian lineage isolates tested. Our results confirm the utility of locus pks15/1 as a molecular marker for identifying Asian lineages of the M. tuberculosis complex. This marker could be of great value in the epidemiological surveillance of TB, especially in countries like Mexico, where the prevalence of such lineages is unknown.
