Dataset Information

Whole-genome sequencing of multidrug-resistant Mycobacterium tuberculosis isolates from Myanmar.

ABSTRACT: Drug-resistant tuberculosis (TB) is a major health threat in Myanmar. An initial study was conducted to explore the potential utility of whole-genome sequencing (WGS) for the diagnosis and management of drug-resistant TB in Myanmar. Fourteen multidrug-resistant Mycobacterium tuberculosis isolates were sequenced. Known resistance genes for a total of nine antibiotics commonly used in the treatment of drug-susceptible and multidrug-resistant TB (MDR-TB) in Myanmar were interrogated through WGS. All 14 isolates were MDR-TB, consistent with the results of phenotypic drug susceptibility testing (DST), and the Beijing lineage predominated. Based on the results of WGS, 9 of the 14 isolates were potentially resistant to at least one of the drugs used in the standard MDR-TB regimen but for which phenotypic DST is not conducted in Myanmar. This study highlights a need for the introduction of second-line DST as part of routine TB diagnosis in Myanmar as well as new classes of TB drugs to construct effective regimens.

SUBMITTER: Aung HL

PROVIDER: S-EPMC5010037 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Whole-genome sequencing of multidrug-resistant Mycobacterium tuberculosis isolates from Myanmar.

Aung Htin Lin HL Tun Thanda T Moradigaravand Danesh D Köser Claudio U CU Nyunt Wint Wint WW Aung Si Thu ST Lwin Thandar T Thinn Kyi Kyi KK Crump John A JA Parkhill Julian J Peacock Sharon J SJ Cook Gregory M GM Hill Philip C PC

Journal of global antimicrobial resistance 20160530

Drug-resistant tuberculosis (TB) is a major health threat in Myanmar. An initial study was conducted to explore the potential utility of whole-genome sequencing (WGS) for the diagnosis and management of drug-resistant TB in Myanmar. Fourteen multidrug-resistant Mycobacterium tuberculosis isolates were sequenced. Known resistance genes for a total of nine antibiotics commonly used in the treatment of drug-susceptible and multidrug-resistant TB (MDR-TB) in Myanmar were interrogated through WGS. Al ...[more]

PMID: 27530852

Similar Datasets

Project description:Improved molecular diagnostic methods for detection drug resistance in Mycobacterium tuberculosis (MTB) strains are required. Resistance to first- and second- line anti-tuberculous drugs has been associated with single nucleotide polymorphisms (SNPs) in particular genes. However, these SNPs can vary between MTB lineages therefore local data is required to describe different strain populations. We used whole genome sequencing (WGS) to characterize 37 extensively drug-resistant (XDR) MTB isolates from Pakistan and investigated 40 genes associated with drug resistance. Rifampicin resistance was attributable to SNPs in the rpoB hot-spot region. Isoniazid resistance was most commonly associated with the katG codon 315 (92%) mutation followed by inhA S94A (8%) however, one strain did not have SNPs in katG, inhA or oxyR-ahpC. All strains were pyrazimamide resistant but only 43% had pncA SNPs. Ethambutol resistant strains predominantly had embB codon 306 (62%) mutations, but additional SNPs at embB codons 406, 378 and 328 were also present. Fluoroquinolone resistance was associated with gyrA 91-94 codons in 81% of strains; four strains had only gyrB mutations, while others did not have SNPs in either gyrA or gyrB. Streptomycin resistant strains had mutations in ribosomal RNA genes; rpsL codon 43 (42%); rrs 500 region (16%), and gidB (34%) while six strains did not have mutations in any of these genes. Amikacin/kanamycin/capreomycin resistance was associated with SNPs in rrs at nt1401 (78%) and nt1484 (3%), except in seven (19%) strains. We estimate that if only the common hot-spot region targets of current commercial assays were used, the concordance between phenotypic and genotypic testing for these XDR strains would vary between rifampicin (100%), isoniazid (92%), flouroquinolones (81%), aminoglycoside (78%) and ethambutol (62%); while pncA sequencing would provide genotypic resistance in less than half the isolates. This work highlights the importance of expanded targets for drug resistance detection in MTB isolates.

Project description:BackgroundThe increase in multidrug-resistant tuberculosis (MDR-TB) severely hampers tuberculosis prevention and control in China, a country with the second highest MDR-TB burden globally. The first nationwide drug-resistant tuberculosis surveillance program provides an opportunity to comprehensively investigate the epidemiological/drug-resistance characteristics, potential drug-resistance mutations, and effective population changes of Chinese MDR-TB.MethodsWe sequenced 357 MDR strains from 4600 representative tuberculosis-positive sputum samples collected during the survey (70 counties in 31 provinces). Drug-susceptibility testing was performed using 18 anti-tuberculosis drugs, representing the most comprehensive drug-resistance profile to date. We used 3 statistical and 1 machine-learning methods to identify drug-resistance genes/single-nucleotide polymorphisms (SNPs). We used Bayesian skyline analysis to investigate changes in effective population size.ResultsEpidemiological/drug-resistance characteristics showed different MDR profiles, co-resistance patterns, preferred drug combination/use, and recommended regimens among 7 Chinese administrative regions. These factors not only reflected the serious multidrug co-resistance and drug misuse but they were also potentially significant in facilitating the development of appropriate regimens for MDR-TB treatment in China. Further investigation identified 86 drug-resistance genes/intergenic regions/SNPs (58 new), providing potential targets for MDR-TB diagnosis and treatment. In addition, the effective population of Chinese MDR-TB displayed a strong expansion during 1993-2000, reflecting socioeconomic transition within the country. The phenomenon of expansion was restrained after 2000, likely attributable to the advances in diagnosis/treatment technologies and government support.ConclusionsOur findings provide an important reference and improved understanding of MDR-TB in China, which are potentially significant in achieving the goal of precision medicine with respect to MDR-TB prevention and treatment.

Project description:BackgroundMultidrug-resistant tuberculosis (MDR-TB) remains a major public health problem in many high tuberculosis (TB) burden countries. Phenotypic drug susceptibility testing (DST) take several weeks or months to result, but line probe assays and Xpert/Rif Ultra assay detect a limited number of resistance conferring gene mutations. Whole genome sequencing (WGS) is an advanced molecular testing method which theoretically can predict the resistance of M. tuberculosis (Mtb) isolates to all anti-TB agents through a single analysis.MethodsHere, we aimed to identify the level of concordance between the phenotypic and WGS-based genotypic drug susceptibility (DS) patterns of MDR-TB isolates. Overall, data for 12 anti-TB medications were analyzed.ResultsIn total, 63 MDR-TB Mtb isolates were included in the analysis, representing 27.4% of the total number of MDR-TB cases in Latvia in 2012-2014. Among them, five different sublineages were detected, and 2.2.1 (Beijing group) and 4.3.3 (Latin American-Mediterranean group) were the most abundant. There were 100% agreement between phenotypic and genotypic DS pattern for isoniazid, rifampicin, and linezolid. High concordance rate (> 90%) between phenotypic and genotypic DST results was detected for ofloxacin (93.7%), pyrazinamide (93.7%) and streptomycin (95.4%). Phenotypic and genotypic DS patterns were poorly correlated for ethionamide (agreement 56.4%), ethambutol (85.7%), amikacin (82.5%), capreomycin (81.0%), kanamycin (85.4%), and moxifloxacin (77.8%). For capreomycin, resistance conferring mutations were not identified in several phenotypically resistant isolates, and, in contrary, for ethionamide, ethambutol, amikacin, kanamycin, and moxifloxacin the resistance-related mutations were identified in several phenotypically sensitive isolates.ConclusionsWGS is a valuable tool for rapid genotypic DST for all anti-TB agents. For isoniazid and rifampicin phenotypic DST potentially can be replaced by genotypic DST based on 100% agreement between the tests. However, discrepant results for other anti-TB agents limit their prescription based solely on WGS data. For clinical decision, at the current level of knowledge, there is a need for combination of genotypic DST with modern, validated phenotypic DST methodologies for those medications which did not showed 100% agreement between the methods.

Project description:Multidrug-resistant (MDR) Mycobacterium tuberculosis complex (MTBC) strains represent a major threat for tuberculosis (TB) control. Treatment of MDR-TB patients is long and less effective, resulting in a significant number of treatment failures. The development of further resistances leads to extensively drug-resistant (XDR) variants. However, data on the individual reasons for treatment failure, e.g. an induced mutational burst, and on the evolution of bacteria in the patient are only sparsely available. To address this question, we investigated the intra-patient evolution of serial MTBC isolates obtained from three MDR-TB patients undergoing longitudinal treatment, finally leading to XDR-TB. Sequential isolates displayed identical IS6110 fingerprint patterns, suggesting the absence of exogenous re-infection. We utilized whole genome sequencing (WGS) to screen for variations in three isolates from Patient A and four isolates from Patient B and C, respectively. Acquired polymorphisms were subsequently validated in up to 15 serial isolates by Sanger sequencing. We determined eight (Patient A) and nine (Patient B) polymorphisms, which occurred in a stepwise manner during the course of the therapy and were linked to resistance or a potential compensatory mechanism. For both patients, our analysis revealed the long-term co-existence of clonal subpopulations that displayed different drug resistance allele combinations. Out of these, the most resistant clone was fixed in the population. In contrast, baseline and follow-up isolates of Patient C were distinguished each by eleven unique polymorphisms, indicating an exogenous re-infection with an XDR strain not detected by IS6110 RFLP typing. Our study demonstrates that intra-patient microevolution of MDR-MTBC strains under longitudinal treatment is more complex than previously anticipated. However, a mutator phenotype was not detected. The presence of different subpopulations might confound phenotypic and molecular drug resistance tests. Furthermore, high resolution WGS analysis is necessary to accurately detect exogenous re-infection as classical genotyping lacks discriminatory power in high incidence settings.

Dataset Information

Whole-genome sequencing of multidrug-resistant Mycobacterium tuberculosis isolates from Myanmar.

Publications

Whole-genome sequencing of multidrug-resistant Mycobacterium tuberculosis isolates from Myanmar.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets