Prevalence and treatment outcome of extensively drug-resistant tuberculosis plus additional drug resistance from the National Clinical Center for Tuberculosis in China: A five-year review

ABSTRACTThe emergence and transmission of extensively drug-resistant tuberculosis (XDR-TB) pose an increasing threat to global TB control. This study aimed to identify the patterns of evolution and transmission dynamics of XDR-TB in populations in a region of China where TB is highly endemic. We analyzed a total of 95 XDR-TB isolates collected from 2003 to 2009 in Chongqing, China. Eight drug resistance genes covering 7 drugs that define XDR-TB were amplified by PCR followed by DNA sequencing. Variable-number tandem repeat 16-locus (VNTR-16) genotyping and genotypic drug resistance profiles were used to determine the evolution or transmission patterns of XDR-TB strains. Our results indicated that the Beijing genotype was predominant (85/95 [89.5%]) in XDR-TB strains, and as many as 40.0% (38/95) of the isolates were distributed into 6 clusters based on VNTR-16 genotyping and drug resistance mutation profiles. All isolates of each cluster harbored as many as six identical resistance mutations in the drug resistance genesrpoB,katG,inhApromoter,embB,rpsL, andgidB. Among the nine cases with continuous isolates from multidrug-resistant (MDR) to XDR-TB, 4 cases represented acquired drug resistance, 4 cases were caused by transmission, and 1 case was due to exogenous superinfection. The XDR-TB epidemic in China is mainly caused by a high degree of clonal transmission, but evolution from MDR to XDR and even superinfection with a new XDR strain can also occur.

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The emerging threat of pre-extensively drug-resistant tuberculosis in West Africa: preparing for large-scale tuberculosis research and drug resistance surveillance

BMC Medicine ◽

10.1186/s12916-016-0704-5 ◽

2016 ◽

Vol 14 (1) ◽

Cited By ~ 20

Author(s):

Florian Gehre ◽

Jacob Otu ◽

Lindsay Kendall ◽

Audrey Forson ◽

Awewura Kwara ◽

...

Keyword(s):

Drug Resistance ◽

West Africa ◽

Large Scale ◽

Drug Resistant ◽

Drug Resistant Tuberculosis ◽

Resistant Tuberculosis ◽

Extensively Drug Resistant

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Drug resistance profile among multi-drug resistant tuberculosis patients at diagnosis and correlation with history of anti-tubercular treatment in a tertiary care center

International Journal of Advances in Medicine ◽

10.18203/2349-3933.ijam20195251 ◽

2019 ◽

Vol 6 (6) ◽

pp. 1918

Author(s):

Rahul Kumar ◽

Rajiv Garg ◽

Silpa Kshetrimayum ◽

Amita Jain

Keyword(s):

Drug Resistance ◽

Drug Sensitivity ◽

Drug Resistant ◽

Second Line ◽

Drug Resistant Tuberculosis ◽

Resistant Tuberculosis ◽

Extensively Drug Resistant ◽

Primary Drug Resistance ◽

Mdr Tb ◽

History Of

Background: Drug Resistant Tuberculosis (DR-TB) is a major threat to the realization of the goal of a TB free world in the near future. It is important to study the reasons for the increasing number of such cases so that effective action can be taken to control this growing epidemic.Methods: Sputum from 36 patients diagnosed with acquired pulmonary Multidrug Resistant Tuberculosis (MDR-TB) were subjected to first- and second-line Drug Sensitivity Testing (DST) after liquid culture in mycobacterium growth Indicator Tube (MGIT). Primary MDR-TB cases were excluded. The relation of the drug sensitivity profile with the history of prior treatment taken was statistically analysed.Results: Majority of the patients had received appropriate treatment, and most had adhered to prescribed treatment. Among the 36 patients, 24(66.7%) were found to be Pre-Extensively Drug Resistant (Pre-XDR-TB) and 4(11.1%) were extensively drug resistant XDR-TB cases. Inappropriate prescription of fluoroquinolone (FQ) was found to be most common. Prior intake of any drug was not found to significantly affect subsequent resistance to that drug.Conclusions: Fluoroquinolone resistance is quite common in patients with DR-TB (66.7%). This study did not find the prior use of FQ or any other drug to significantly affect subsequent resistance to the drug. Primary drug resistance is thus a major concern. 11.1% patients were found to be XDR-TB cases. Hence DST for first- and second-line drugs should be done at the time of diagnosis to avoid failure of treatment with a predesigned regimen.

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