Dataset Information

Genotyping and drug-resistance epidemiology of mycobacterium tuberculosis in Xuzhou, China.

ABSTRACT: BACKGROUND:To explore the genetic diversity and drug resistance status of MTB in Xuzhou, China. METHODS:A total of 325 clinical MTB strains were genotyped by spacer-oligonucleotide typing (spoligotyping) and mycobacterial interspersed repetitive unit variable number of tandem repeats (MIRU-VNTR). Phenotypic resistance was assessed by drug susceptibility testing (DST). RESULT:Based on the spoligotyping method, 325 MTB isolates were classified into 5 known genotypes and 12 unknown genotypes, and the largest branch comprised 268 strains belonging to the Beijing family. Based on the 15-loci VNTR typing method, 325 MTB isolates were divided into 35 clusters and 220 unique patterns. Compared to the low discriminatory power of spoligotyping genotyping (HGDI = 0.3444), 15-loci VNTR genotyping had a significantly higher discriminatory power for all strains (HGDI = 0.9980), particularly for the Beijing family strains (HGDI = 0.9892). When spoligotyping and 15-loci VNTR methods were used together, the discriminatory power increased to 0.9991. The Beijing family strain presented increased risks for developing multi-drug resistance TB (P < 0.05). CONCLUSION:The Beijing family isolates is the most prevalent strains in Xuzhou. Spoligotyping, in combination with 15-loci MIRU-VNTR, is useful for epidemiological analysis of MTB transmission in Xuzhou.

SUBMITTER: Zhang H

PROVIDER: S-EPMC6965968 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Phenotypic drug susceptibility testing (DST) for tuberculosis (TB) requires weeks to yield results. Although molecular tests rapidly detect drug resistance-associated mutations (DRMs), they are not scalable to cover the full genome and the many DRMs that can predict resistance. Whole-genome sequencing (WGS) methods are scalable, but if conducted directly on sputum, typically require a target enrichment step, such as nucleic acid amplification. We developed a targeted isothermal amplification-nanopore sequencing workflow for rapid prediction of drug resistance of TB isolates. We used recombinase polymerase amplification (RPA) to perform targeted isothermal amplification (37°C for 90 min) of three regions within the Mycobacterium tuberculosis genome, followed by nanopore sequencing on the MinION. We tested 29 mycobacterial genomic DNA extracts from patients with drug-resistant (DR) TB and compared our results to those of WGS by Illumina and phenotypic DST to evaluate the accuracy of prediction of resistance to rifampin and isoniazid. Amplification by RPA showed fidelity equivalent to that of high-fidelity PCR (100% concordance). Nanopore sequencing generated DRM predictions identical to those of WGS, with considerably faster sequencing run times of minutes rather than days. The sensitivity and specificity of rifampin resistance prediction for our workflow were 96.3% (95% confidence interval [CI], 81.0 to 99.9%) and 100.0% (95% CI, 15.8 to 100.0%), respectively. For isoniazid resistance prediction, the sensitivity and specificity were 100.0% (95% CI, 86.3 to 100.0%) and 100.0% (95% CI, 39.8 to 100.0%), respectively. The workflow consumable costs per sample are less than £100. Our rapid and low-cost drug resistance genotyping workflow provides accurate prediction of rifampin and isoniazid resistance, making it appropriate for use in resource-limited settings. IMPORTANCE Current methods for diagnosing drug-resistant tuberculosis are time consuming, resulting in delays in patients receiving treatment and in transmission onwards. They also require a high level of laboratory infrastructure, which is often only available at centralized facilities, resulting in further delays to diagnosis and additional barriers to deployment in resource-limited settings. This article describes a new workflow that can diagnose drug-resistant TB in a shorter time, with less equipment, and for a lower price than current methods. The amount of TB DNA is first increased without the need for bulky and costly thermocycling equipment. The DNA is then read using a portable sequencer called a MinION, which indicates whether there are tell-tale changes in the DNA that indicate whether the TB strain is drug resistant. Our workflow could play an important role in the future in the fight against the public health challenge that is TB drug resistance.

Project description:BACKGROUND:The prevalence of drug-resistant tuberculosis (DR-TB) has brought severe challenges to the prevention and control of tuberculosis. Studies have explored the status of antituberculosis drug (ATD) resistance in different regions of China. However, few studies have focused on DR-TB in Sichuan to date. Due to the large population in Sichuan, detailed investigations of the DR-TB burden in Sichuan are needed. The objective of this study was to investigate the drug resistance characteristics of TB isolates from tuberculosis patients with and without HIV (TB-HIV patients and TBw/oHIV patients) in Chengdu, Sichuan, China. METHODS:Isolates from respiratory samples of TBw/oHIV patients and TB-HIV patients hospitalized between January 2014 and December 2017 were collected. Nontuberculosis mycobacteria (NTM) were excluded. Drug sensitivity testing (DST) was performed according to the dilution method in microplates with 4 first-line ATDs and 8 second-line ATDs. TB strains were separated according to patient treatment history, patient age, calendar year and GeneXpert MTB/RIF (GeneXpert) assay results for further analysis. RESULTS:For the 7470 patients recruited, the multidrug-resistant tuberculosis (MDR-TB) rate was 2.1-fold (14.6% vs. 6.8%) higher than the national baseline level. The repeatedly admitted patients were more likely to have a resistance profile than the first-time-admitted cases in both the TB-only group (P<0.05) and the TB-HIV corresponding group (P<0.05). Among the 7273 TBw/oHIV cases and 197 TB-HIV cases, the positivity rates of acid-fast bacilli (AFB) in the TB-HIV group were significantly lower than those in the TBw/oHIV group (P<0.05). The repeatedly admitted TB-HIV patients had lower resistance rates to INH than the repeatedly admitted TBw/oHIV patients (24.4% vs. 41.5%, P<0.05). The Rifampicin-resistant TB strains in the TBw/oHIV group were more likely to be resistant to INH in the repeatedly admitted group than those in the first-time admitted patients (P<0.05). The proportions of XDR (3.6% vs. 1.3%, P<0.05) and XDR-TB/MDR-TB (7.3% vs. 2.2%, P<0.05) in all TB-HIV patients were significantly higher than those in all TBw/oHIV patients. The ratio of XDR-TB was significantly higher in the TB-HIV group than in the TBw/oHIV group (30.4% vs. 9.0%, P<0.05) and the all TB group (9.0% vs. 10.1%, P<0.05). Regarding age, the <25-year-old TB-HIV patients (9.1% vs. 0.7%, P<0.05) and 25~44-year-old TB-HIV patients (5.2% vs. 2.4%, P<0.05) were more likely to have a higher XDR proportion than their TBw/oHIV counterparts. The ATD-resistance profile in terms of different years from high to low was 2014>2015>2016?2017 for TBw/oHIV patients. The same trend was also observed for TB-HIV patients: 2014>2015>2016?2017. The GeneXpert TB-positive rate in the TBw/oHIV group was higher than that in the TB-HIV group [81%(639/792) vs. 65% (13/20), P<0.05]. In TBw/oHIV cases, the agreement was 92.3% and the Kappa value was 0.75. In TB-HIV cases, the agreement was 85.0% and the Kappa value was 0.32. CONCLUSION:In Sichuan, ATD resistance has improved since 2014, but to date, it remains severe. The different resistance profiles of TBw/oHIV patients and TB-HIV patients indicates the need for personalized treatment plans. Specifically, the GeneXpert assay might be more suitable for TBw/oHIV patients than for TB-HIV patients.

Dataset Information

Genotyping and drug-resistance epidemiology of mycobacterium tuberculosis in Xuzhou, China.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets