scholarly journals Additional Drug Resistance in Mycobacterium tuberculosis Isolates From Resected Cavities Among Patients With Multidrug-Resistant or Extensively Drug-Resistant Pulmonary Tuberculosis

2011 ◽  
Vol 54 (6) ◽  
pp. e51-e54 ◽  
Author(s):  
R. R. Kempker ◽  
A. S. Rabin ◽  
K. Nikolaishvili ◽  
I. Kalandadze ◽  
S. Gogishvili ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Multidrug Resistant ◽  
Drug Resistant ◽  
Extensively Drug Resistant

scholarly journals Prevalence and Genetic Characterization of Second-Line Drug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis in Rural China

2013 ◽  
Vol 57 (8) ◽  
pp. 3857-3863 ◽  
Author(s):  
Yi Hu ◽  
Sven Hoffner ◽  
Linlin Wu ◽  
Qi Zhao ◽  
Weili Jiang ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Mycobacterium Tuberculosis ◽  
Dna Sequences ◽  
Rural China ◽  
Multidrug Resistant ◽  
Drug Resistant ◽  
Second Line ◽  
Content Type ◽  
Extensively Drug Resistant ◽  
Line Drug

ABSTRACTThis study aimed to investigate the prevalence of resistance to second-line antituberculosis (anti-TB) drugs and its association with resistance-related mutations inMycobacterium tuberculosisisolated in China. In the present study, we collected 380 isolates from a population-based study in China and tested the drug susceptibility to first- and selected second-line drugs. These results were compared with polymorphisms in the DNA sequences of genes associated with drug resistance and MIC values of the studied second-line drugs. Of 43 multidrug-resistantM. tuberculosisisolates, 13 showed resistance to fluoroquinolones or injectable second-line drugs (preextensively drug-resistant TB [pre-XDR-TB]), and 4 were resistant to both and thus defined as extensively drug-resistant TB (XDR-TB). Age and previous TB therapy, including use of second-line drugs, were two independent factors associated with increased resistance to both first- and second-line drugs. Molecular analysis identified the most frequent mutations in the resistance-associated genes: D94G ingyrA(29.1%) and A1401G inrrs(30.8%). Meanwhile, all 4 XDR-TB isolates had a mutation ingyrA, and 3 of them carried the A1401G mutation inrrs. Mutations ingyrAandrrswere associated with high-level resistance to fluoroquinolones and the second-line injectable drugs. In addition to the identification of resistance-associated mutations and development of a rapid molecular test to diagnose the second-line drug resistance, it should be a priority to strictly regulate the administration of second-line drugs to maintain their efficacy to treat multidrug-resistant TB.

scholarly journals Analysis of drug resistance and mutation profiles in Mycobacterium tuberculosis isolates in a surveillance site in Beijing, China

2021 ◽  
Vol 49 (1) ◽  
pp. 030006052098493
Author(s):  
Jie Zhang ◽  
Yixuan Ren ◽  
Liping Pan ◽  
Junli Yi ◽  
Tong Guan ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Mycobacterium Tuberculosis ◽  
Drug Testing ◽  
Multidrug Resistant ◽  
High Rate ◽  
Drug Resistant ◽  
Surveillance Site ◽  
Mdr Tb ◽  
Previously Treated Patients ◽  
Beijing China

Objective This study analyzed drug resistance and mutations profiles in Mycobacterium tuberculosis isolates in a surveillance site in Huairou District, Beijing, China. Methods The proportion method was used to assess drug resistance profiles for four first-line and seven second-line anti-tuberculosis (TB) drugs. Molecular line probe assays were used for the rapid detection of resistance to rifampicin (RIF) and isoniazid (INH). Results Among 235 strains of M. tuberculosis, 79 (33.6%) isolates were resistant to one or more drugs. The isolates included 18 monoresistant (7.7%), 19 polyresistant (8.1%), 28 RIF-resistant (11.9%), 24 multidrug-resistant (MDR) (10.2%), 7 pre-extensively drug-resistant (XDR, 3.0%), and 2 XDR strains (0.9%). A higher rate of MDR-TB was detected among previously treated patients than among patients with newly diagnosed TB (34.5% vs. 6.8%). The majority (62.5%) of RIF-resistant isolates exhibited a mutation at S531L in the DNA-dependent RNA polymerase gene. Meanwhile, 62.9% of INH-resistant isolates carried a mutation at S315T1 in the katG gene. Conclusion Our results confirmed the high rate of drug-resistant TB, especially MDR-TB, in Huairou District, Beijing, China. Therefore, detailed drug testing is crucial in the evaluation of MDR-TB treatment.

Metabolic profiles of multidrug resistant and extensively drug resistant Mycobacterium tuberculosis unveiled by metabolomics

Tuberculosis ◽  
2021 ◽  
Vol 126 ◽  
pp. 102043
Author(s):  
Amanda Mendes Rêgo ◽  
Duanne Alves da Silva ◽  
Nicole Victor Ferreira ◽  
Lucindo Cardoso de Pina ◽  
Joseph A.M. Evaristo ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Multidrug Resistant ◽  
Metabolic Profiles ◽  
Drug Resistant ◽  
Extensively Drug Resistant

scholarly journals Comparison of In Vitro Activity and MIC Distributions between the Novel Oxazolidinone Delpazolid and Linezolid against Multidrug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis in China

2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Zhaojing Zong ◽  
Wei Jing ◽  
Jin Shi ◽  
Shu'an Wen ◽  
Tingting Zhang ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Novel Mutation ◽  
Multidrug Resistant ◽  
23S Rrna ◽  
Drug Resistant ◽  
Content Type ◽  
Extensively Drug Resistant ◽  
Significant Difference ◽  
Mdr Tb

ABSTRACT Oxazolidinones are efficacious in treating mycobacterial infections, including tuberculosis (TB) caused by drug-resistant Mycobacterium tuberculosis. In this study, we compared the in vitro activities and MIC distributions of delpazolid, a novel oxazolidinone, and linezolid against multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) in China. Additionally, genetic mutations in 23S rRNA, rplC, and rplD genes were analyzed to reveal potential mechanisms underlying the observed oxazolidinone resistance. A total of 240 M. tuberculosis isolates were included in this study, including 120 MDR-TB isolates and 120 XDR-TB isolates. Overall, linezolid and delpazolid MIC90 values for M. tuberculosis isolates were 0.25 mg/liter and 0.5 mg/liter, respectively. Based on visual inspection, we tentatively set epidemiological cutoff (ECOFF) values for MIC determinations for linezolid and delpazolid at 1.0 mg/liter and 2.0 mg/liter, respectively. Although no significant difference in resistance rates was observed between linezolid and delpazolid among XDR-TB isolates (P > 0.05), statistical analysis revealed a significantly greater proportion of linezolid-resistant isolates than delpazolid-resistant isolates within the MDR-TB group (P = 0.036). Seven (53.85%) of 13 linezolid-resistant isolates were found to harbor mutations within the three target genes. Additionally, 1 isolate exhibited an amino acid substitution (Arg126His) within the protein encoded by rplD that contributed to high-level resistance to linezolid (MIC of >16 mg/liter), compared to a delpazolid MIC of 0.25. In conclusion, in vitro susceptibility testing revealed that delpazolid antibacterial activity was comparable to that of linezolid. A novel mutation within rplD that endowed M. tuberculosis with linezolid, but not delpazolid, resistance was identified.

scholarly journals Tuberculose Multirresistente por Estirpes da Família Beijing, em Doentes de Lisboa, Portugal: Estudo Preliminar

2017 ◽  
Vol 30 (3) ◽  
pp. 175 ◽  
Author(s):  
Fernando Maltez ◽  
Teresa Martins ◽  
Diana Póvoas ◽  
João Cabo ◽  
Helena Peres ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Past History ◽  
Multidrug Resistant ◽  
Resistance Pattern ◽  
Drug Resistant ◽  
Beijing Family ◽  
Resistant Tuberculosis ◽  
Extensively Drug Resistant ◽  
Number Of Patients ◽  
Drug Resistant Strains

Introduction: Beijing family strains of Mycobacterium tuberculosis are associated with multidrug-resistance. Although strains of the Lisboa family are the most common among multidrug-resistant and extensively drug-resistant patients in the region, several studies have reported the presence of the Beijing family. However, the features of patients from whom they were isolated, are not yet known.Material and Methods: Retrospective study involving 104 multidrug-resistant and extensively drug-resistant strains of Mycobacterium tuberculosis, from the same number of patients, isolated and genotyped between 1993 and 2015 in Lisbon. We assessed the prevalence of strains of both families and the epidemiologic and clinical features of those infected with Beijing family strains.Results: Seventy-four strains (71.2%) belonged to the Lisboa family, 25 (24.0%) showed a unique genotypic pattern and five (4.8%) belonged to the Beijing family, the latter identified after 2009. Those infected with Beijing family strains were angolan (n = 1), ukrainian (n = 2) and portuguese (n = 2), mainly young-aged and, four of five immunocompetent and with no past history of tuberculosis. All had multidrug-resistant tuberculosis. We did not find any distinctive clinical or radiological features, neither a predominant resistance pattern. Cure rate was high (four patients).Discussion: Although the number of infected patients with Beijing strains was small, it suggests an important proportion of primary tuberculosis, a potential for transmission in the community but also a better clinical outcome when compared to other reported strains, such as W-Beijing and Lisboa.Conclusion: Although Lisboa family strains account for most of the multidrug and extensively drug-resistant tuberculosis cases in Lisbon area, Beijing strains are transmitted in the city and might change the local characteristics of the epidemics.

scholarly journals Genotypes of Mycobacterium tuberculosis isolates circulating in Shaanxi Province, China

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0242971
Author(s):  
Yan Li ◽  
Yu Pang ◽  
Tianhua Zhang ◽  
Xiaoping Xian ◽  
Jian Yang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Drug Resistance ◽  
Mycobacterium Tuberculosis ◽  
Multidrug Resistant ◽  
Shaanxi Province ◽  
Drug Resistant ◽  
Beijing Family ◽  
Tuberculosis Patients ◽  
Smear Positive Pulmonary Tuberculosis ◽  
Discriminatory Index

Objectives The prevalence of drug-resistant TB in Shaanxi Province is higher than other areas. This study was aimed to investigate the genetic diversity and epidemiology of Mycobacterium tuberculosis clinical strains in Shaanxi Province, China. Methods From January to December 2016, a total of 298 Mycobacterium tuberculosis clinical isolates from smear-positive pulmonary tuberculosis patients were genotyped by Mcspoligotyping and 15-locus VNTR. Results We found that the Beijing family strains was the most prominent family(81.54%, 243/298). Other family strains included T family(9.06%, 27/298), U family(0.67%, 2/298), LAM9 family(0.34%, 1/298) and Manu family(0.34%, 1/298). The rates of multidrug-resistant (MDR) M.Tuberculosis, age, type of case and education between Beijing and non-Beijing family strains were not statistically different, while the distribution in the three different regions among these was statistically significant. VNTR results showed that strains were classified into 280 genotypes, and 33 (11.07%) strains could be grouped into 14 clusters. 11 of the 15-VNTR loci were highly or moderately discriminative according to the Hunter-Gaston discriminatory index. Conclusions We concluded that the Beijing family genotype was the most prevalent genotype and 15-locus VNTR typing might be suitable for genotyping of M. tuberculosis in Shaanxi Province. There was less association between Beijing family genotypes and drug resistance in our study area.

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