BackgroundPhylogeographic composition of M. tuberculosis populations reveals associations between lineages and human populations that might have implications for the development of strategies to control the disease. In Latin America, lineage 4 or the Euro-American, is predominant with considerable variations among and within countries. In Colombia, although few studies from specific localities have revealed differences in M. tuberculosis populations, there are still areas of the country where this information is lacking, as is a comparison of Colombian isolates with those from the rest of the world.Principal FindingsA total of 414 M. tuberculosis isolates from adult pulmonary tuberculosis cases from three Colombian states were studied. Isolates were genotyped using IS6110-restriction fragment length polymorphism (RFLP), spoligotyping, and 24-locus Mycobacterial interspersed repetitive units variable number tandem repeats (MIRU-VNTRs). SIT42 (LAM9) and SIT62 (H1) represented 53.3% of isolates, followed by 8.21% SIT50 (H3), 5.07% SIT53 (T1), and 3.14% SIT727 (H1). Composite spoligotyping and 24-locus MIRU- VNTR minimum spanning tree analysis suggest a recent expansion of SIT42 and SIT62 evolved originally from SIT53 (T1). The proportion of Haarlem sublineage (44.3%) was significantly higher than that in neighboring countries. Associations were found between M. tuberculosis MDR and SIT45 (H1), as well as HIV-positive serology with SIT727 (H1) and SIT53 (T1).ConclusionsThis study showed the population structure of M. tuberculosis in several regions from Colombia with a dominance of the LAM and Haarlem sublineages, particularly in two major urban settings (Medellín and Cali). Dominant spoligotypes were LAM9 (SIT 42) and Haarlem (SIT62). The proportion of the Haarlem sublineage was higher in Colombia compared to that in neighboring countries, suggesting particular conditions of co-evolution with the corresponding human population that favor the success of this sublineage.

IntroductionTuberculosis (TB) remains a primary public health problem worldwide. The number of multidrug-resistant tuberculosis (MDR TB) cases has increased in recent years in Colombia. Knowledge of M. tuberculosis genotypes defined by spoligotyping can help determine the circulation of genotypes that must be controlled to prevent the spread of TB.ObjectiveTo describe the genotypes of M. tuberculosis using spoligotyping in resistant and drug-sensitive isolates and their possible associations with susceptibility to first-line drugs.MethodsAn analytical observational study was conducted that included 741 isolates of M. tuberculosis from patients. The isolates originated from 31 departments and were obtained by systematic surveillance between 1999 and 2012.ResultsIn total 61.94% of the isolates were resistant to 1 or more drugs, and 147 isolates were MDR. In total, 170 genotypes were found in the population structure of Colombian M. tuberculosis isolates. The isolates were mainly represented by four families: LAM (39.9%), Haarlem (19%), Orphan (17%) and T (9%). The SIT42 (LAM 9) was the most common genotype and contained 24.7% of the isolates, followed by the genotypes SIT62 (Haarlem1), SIT53 (T1), and SIT50 (H3). A high clustering of isolates was evident with 79.8% of the isolates classified into 32 groups. The Beijing family was associated with resistant isolates, whereas the Haarlem and T families were associated with sensitive isolates. The Haarlem family was also associated with grouped isolates (p = 0.031).ConclusionsA high proportion (approximately 80%) of isolates was found in clusters; these clusters were not associated with resistance to first-line drugs. The Beijing family was associated with drug resistance, whereas the T and Haarlem families were associated with susceptibility in the Colombian isolates studied.

Introducción. Una tercera parte de los casos nuevos de tuberculosis se atribuye a la propagación del HIV. En 2012, se presentaron en Colombia 1.397 casos de tuberculosis concomitante con la infección por HIV, es decir, 11,8 % del total de notificados. El uso de las herramientas de epidemiología molecular contribuye a una mejor comprensión de la transmisión de la enfermedad.Objetivo. Caracterizar los aislamientos clínicos de Mycobacterium tuberculosis de individuos positivos para HIV recibidos en el Laboratorio Nacional de Referencia del Instituto Nacional de Salud.Materiales y métodos. Se hizo un estudio observacional descriptivo. Se estudiaron 63 aislamientos de individuos con tuberculosis e infección por HIV mediante pruebas de identificación, sensibilidad y genotipificación.Resultados. Dos de los casos nuevos (3,3 %) eran resistentes a rifampicina y uno (1,6 %) a isoniacida, en tanto que tres (5,0 %) lo eran a la isoniacida combinada con estreptomicina. Los casos previamente tratados fueron sensibles. No se evidenció multirresistencia. Hubo 20 (31,7 %) aislamientos de la familia genética LAM9, 8 (12,7 %) de la H1 y 7 (11,1 %) de la T1 . Diecinueve aislamientos correspondieron a patrones huérfanos. Se observó un único agrupamiento entre los aislamientos analizados. No se encontraron diferencias estadísticamente significativas entre la resistencia a fármacos y las familias genéticas.Conclusión. La resistencia encontrada demostró la transmisión de cepas resistentes a rifampicina e isoniacida. Las familias genéticas LAM9, T1 y H1 corresponden a las descritas en la población general. No se evidenció transmisión activa en los aislamientos estudiados. Se necesitan estudios más completos para conocer la situación real de la infección concomitante de tuberculosis y HIV en el país.

No cases of the disease caused by this zoonotic agent were documented in the departments of Antioquia, Boyacá and Cundinamarca.

Resumen Definir la autoría en artículos y documentos científicos es un proceso esencial y complejo, que encierra subjetividad y depende de convenios establecidos en general de palabra, lo que puede ocasionar conflictos entre los investigadores. Se han publicado algunas guías con lineamientos generales para mejorar esta práctica, sin embargo son pocos los procedimientos cuantitativos para precisar autoría y coautoría de un escrito científico, y no hay consenso para definir los autores y el orden en que deben aparecer. Con este artículo intentamos rescatar algunos criterios y consideraciones para determinar el listado de autores en textos científicos.