scholarly journals Increasing prevalence of resistance to second-line drugs among multidrug-resistant Mycobacterium tuberculosis isolates in Kuwait

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Noura M. Al-Mutairi ◽  
Suhail Ahmad ◽  
Eiman Mokaddas

AbstractMolecular methods detect genetic mutations associated with drug resistance. This study detected resistance-conferring mutations in gyrA/gyrB for fluoroquinolones and rrs/eis genes for second-line injectable drugs (SLIDs) among multidrug-resistant Mycobacterium tuberculosis (MDR-TB) isolates in Kuwait. Fifty pansusceptible M. tuberculosis and 102 MDR-TB strains were tested. Phenotypic susceptibility testing was performed by MGIT 960 system using SIRE drug kit. GenoType MTBDRsl version 1 (gMTBDRslv1) and GenoType MTBDRsl version 2 (gMTBDRslv2) tests were used for mutation detection. Results were validated by PCR-sequencing of respective genes. Fingerprinting was performed by spoligotyping. No mutations were detected in pansusceptible isolates. gMTBDRslv1 detected gyrA mutations in 12 and rrs mutations in 8 MDR-TB isolates. gMTBDRsl2 additionally detected gyrB mutations in 2 and eis mutation in 1 isolate. Mutations in both gyrA/gyrB and rrs/eis were not detected. gMTBDRslv1 also detected ethambutol resistance-conferring embB mutations in 59 isolates. Although XDR-TB was not detected, frequency of resistance-conferring mutations for fluoroquinolones or SLIDs was significantly higher among isolates collected during 2013–2019 versus 2006–2012. Application of both tests is warranted for proper management of MDR-TB patients in Kuwait as gMTBDRslv2 detected resistance to fluoroquinolones and/or SLIDs in 3 additional isolates while gMTBDRslv1 additionally detected resistance to ethambutol in 58% of MDR-TB isolates.

2020 ◽  
Author(s):  
Eung Gu Lee ◽  
Jinsoo Min ◽  
Ji Young Kang ◽  
Sung Kyoung Kim ◽  
Jin Woo Kim ◽  
...  

Abstract Background: The emergence of drug-resistant tuberculosis (DR-TB) is a major healthcare concern worldwide. Here, we analyzed age-related trends in DR-TB rates in South Korea.Methods: Drug susceptibility test results were collected from patients with culture-confirmed TB between 2015 and 2018 from eight university-affiliated hospitals. Patients were divided into three subgroups: younger (15–34 years), middle (35–59 years), and older (≥60 years) to compare drug-resistance patterns.Results: Among the 4,417 cases investigated, 179 (4.1%), 53 (1.2%), and 316 (7.2%) were multidrug-resistant TB (MDR-TB), rifampicin-mono-resistant TB (RR-TB), and isoniazid-mono-resistant TB (Hr-TB), respectively. Proportions of Hr-TB cases were similar among the three groups (11.2%, 12.2%, and 10.4% in the younger, middle, and older groups, respectively). MDR/RR-TB case numbers decreased significantly as age increased (8.6%, 6.3%, 3.3%, respectively). Proportions of MDR/RR-TB among retreated patients in the younger generation decreased from 50.0% to 18.2%, but remained higher than that in the older generation. Fluoroquinolone resistance was highest among second-line drugs, and there were no differences in resistance to fluoroquinolones and second-line injectable drugs among the three age groups.Conclusions: The number of MDR/RR-TB cases was highest in young patients. Effective public health interventions should include increased focus on rifampicin resistance in young patients.


2016 ◽  
Vol 61 (2) ◽  
Author(s):  
Florence Brossier ◽  
Anne Pham ◽  
Christine Bernard ◽  
Alexandra Aubry ◽  
Vincent Jarlier ◽  
...  

ABSTRACT The second-line injectable drugs (SLID, i.e., amikacin, kanamycin, capreomycin) are key drugs for the treatment of multidrug-resistant tuberculosis. Mutations in rrs region 1400, tlyA, and eis promoter are associated with resistance to SLID, to capreomycin, and to kanamycin, respectively. In this study, the sequencing data of SLID resistance-associated genes were compared to the results of phenotypic drug susceptibility testing by the proportion method for the SLID in 206 multidrug-resistant clinical isolates of Mycobacterium tuberculosis collected in France. Among the 153 isolates susceptible to the 3 SLID, 145 showed no mutation, 1 harbored T1404C and G1473A mutations in rrs, and 7 had an eis promoter mutation. Among the 53 strains resistant to at least 1 of the SLID, mutations in rrs accounted for resistance to amikacin, capreomycin, and kanamycin for 81%, 75%, and 44% of the isolates, respectively, while mutations in eis promoter were detected in 44% of the isolates resistant to kanamycin. In contrast, no mutations in tlyA were observed in the isolates resistant to capreomycin. The discrepancies observed between the genotypic (on the primary culture) and phenotypic drug susceptibility testing were explained by (i) resistance to SLID with MICs close to the critical concentration used for routine DST and not detected by phenotypic testing (n = 8, 15% of SLID-resistant strains), (ii) low-frequency heteroresistance not detected by sequencing of drug resistance-associated genes on the primary culture (n = 8, 15% of SLID-resistant strains), and (iii) other resistance mechanisms not yet characterized (n = 7, 13% of SLID-resistant strains).


2021 ◽  
Vol 49 (1) ◽  
pp. 030006052098493
Author(s):  
Jie Zhang ◽  
Yixuan Ren ◽  
Liping Pan ◽  
Junli Yi ◽  
Tong Guan ◽  
...  

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.


2017 ◽  
Vol 8 (1) ◽  
pp. 33-43 ◽  
Author(s):  
Aleksandr I. Ilin ◽  
Murat E. Kulmanov ◽  
Ilya S. Korotetskiy ◽  
Marina V. Lankina ◽  
Gulshara K. Akhmetova ◽  
...  

Emergence of multidrug resistant strains ofMycobacterium tuberculosis(MDR-TB) threatens humanity. This problem was complicated by the crisis in development of new anti-tuberculosis antibiotics. Induced reversion of drug resistance seems promising to overcome the problem. Successful clinical trial of a new anti-tuberculosis nanomolecular complex FS-1 has demonstrated prospectively of this approach in combating MDR-TB. Several clinical MDR-TB cultures were isolated from sputum samples prior and in the process of the clinical trial. Every isolate was tested for susceptibility to antibiotics and then they were sequenced for comparative genomics. It was found that the treatment with FS-1 caused an increase in the number of antibiotic susceptible strains among Mtb isolates that was associated with a general increase of genetic heterogeneity of the isolates. Observed impairing of phthiocerol dimycocerosate biosynthesis by disruptive mutations inppsACDsubunits indicated a possible virulence remission for the sake of persistence. It was hypothesized that the FS-1 treatment eradicated the most drug resistant Mtb variants from the population by aggravating the fitness cost of drug resistance mutations. Analysis of distribution of these mutations in the global Mtb population revealed that many of them were incompatible with each other and dependent on allelic states of many other polymorphic loci. The latter discovery may explain the negative correlation between the genetic heterogeneity of the population and the level of drug tolerance. To the best of our knowledge, this work was the first experimental confirmation of the drug induced antibiotic resistance reversion by the induced synergy mechanism that previously was predicted theoretically.


2015 ◽  
Vol 59 (12) ◽  
pp. 7805-7810 ◽  
Author(s):  
Johana Rueda ◽  
Teresa Realpe ◽  
Gloria Isabel Mejia ◽  
Elsa Zapata ◽  
Juan Carlos Rozo ◽  
...  

ABSTRACTEthionamide (ETH) is an antibiotic used for the treatment of multidrug-resistant (MDR) tuberculosis (TB) (MDR-TB), and its use may be limited with the emergence of resistance in theMycobacterium tuberculosispopulation. ETH resistance inM. tuberculosisis phenomenon independent or cross related when accompanied with isoniazid (INH) resistance. In most cases, resistance to INH and ETH is explained by mutations in theinhApromoter and in the following genes:katG,ethA,ethR,mshA,ndh, andinhA. We sequenced the above genes in 64M. tuberculosisisolates (n= 57 ETH-resistant MDR-TB isolates;n= 3 ETH-susceptible MDR-TB isolates; andn= 4 fully susceptible isolates). Each isolate was tested for susceptibility to first- and second-line drugs using the agar proportion method. Mutations were observed in ETH-resistant MDR-TB isolates at the following rates: 100% inkatG, 72% inethA, 45.6% inmshA, 8.7% inndh, and 33.3% ininhAor its promoter. Of the three ETH-susceptible MDR-TB isolates, all showed mutations inkatG; one had a mutation inethA, and another, inmshAandinhA. Finally, of the four fully susceptible isolates, two showed no detectable mutation in the studied genes, and two had mutations inmshAgene unrelated to the resistance. Mutations not previously reported were found in theethA,mshA,katG, andndhgenes. The concordance between the phenotypic susceptibility testing to INH and ETH and the sequencing was 1 and 0.45, respectively. Among isolates exhibiting INH resistance, the high frequency of independent resistance and cross-resistance with ETH in theM. tuberculosisisolates suggests the need to confirm the susceptibility to ETH before considering it in the treatment of patients with MDR-TB.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Tichaona Sagonda ◽  
Lucy Mupfumi ◽  
Rumbidzai Manzou ◽  
Beauty Makamure ◽  
Mqondisi Tshabalala ◽  
...  

We conducted a cross-sectional study of second line drug resistance patterns and genetic diversity of MDR-TB isolates archived at the BRTI-TB Laboratory, Harare, between January 2007 and December 2011. DSTs were performed for second line antituberculosis drugs. XDR-TB strains were defined as MDR-TB strains with resistance to either kanamycin and ofloxacin or capreomycin and ofloxacin. Strain types were identified by spoligotyping. No resistance to any second line drugs was shown in 73% of the isolates, with 23% resistant to one or two drugs but not meeting the definition of XDR-TB. A total of 26 shared types were identified, and 18 (69%) matched preexisting shared types in the current published spoligotype databases. Of the 11 out of 18 clustered SITs, 4 predominant (>6 isolates per shared type) were identified. The most and least abundant types were SIT 1468 (LAM 11-ZWE) with 12 (18%) isolates and SIT 53 (T1) with 6 (9%) isolates, respectively. XDR-TB strains are rare in Zimbabwe, but the high proportion of “pre-XDR-TB” strains and treatment failure cases is of concern. The genetic diversity of the MDR-TB strains showed no significant association between SITs and drug resistance.


2021 ◽  
Vol 13 (3) ◽  
pp. 256-60
Author(s):  
Towifah Fauziah Choerunisa ◽  
Leni Lismayanti ◽  
Tiene Rostini ◽  
Ryan Bayusantika ◽  
Ida Parwati

BACKGROUND: Tuberculosis (TB) infection is one of the most prominent health issues in the world, including in Indonesia. TB is evolving into multidrug-resistant tuberculosis (MDR-TB) and requiring second-line TB drugs. Mycobacterium growth indicator tube (MGIT) is the gold standard for susceptibility testing of second-line TB drugs. Alternatively, line probe assay (LPA), which detects genes resistant to second-line TB drugs, takes a shorter time to run. This study aims to compare MGIT and LPA's ability to detect TB resistance to second-line TB drugs and observe mutation patterns of genes encoding second-line TB drugs.METHODS: This was an observational analytic study, using cross-sectional method. The data were acquired from the MDR-TB clinic’s medical records at the Dr. Hasan Sadikin Hospital from September to December 2019. LPA and MGIT test were conducted at the Health Laboratory Hall of West Java Province, then tested using Kolmogorov-Smirnov and chi-square statistic.RESULTS: From 121 subjects, 113 people were not resistant to the second-line TB drugs, which was examined using both LPA and MGIT (93.4%), p=0.991. Mutations were found in gyrA and rrs gene. There was no significant difference between the proportion of subjects resistant to the second-line of TB drugs tested using LPA and MGIT.CONCLUSION: LPA is an alternative method to MGIT because it requires a shorter time and reduces the risk of exposure that will improve MDR-TB patients management.KEYWORDS: line probe assay (LPA), multidrug-resistant TB, mycobacterium growth indicator tube (MGIT), second-line TB drugs 


2020 ◽  
Vol 13 (10) ◽  
pp. 2150-2155
Author(s):  
Hossam A. Abdelsadek ◽  
Hassan M. Sobhy ◽  
Kh. F. Mohamed ◽  
Sahar H. A. Hekal ◽  
Amany N. Dapgh ◽  
...  

Background and Aim: Mycobacterium tuberculosis complex (MTBC) is a group of mycobacteria that are important human pathogens. Mycobacterium tuberculosis and Mycobacterium bovis cause serious chronic life-threatening disease and also significant economic losses in both production and remedication. Recently, emergence of multidrug-resistant tuberculosis (MDR-TB) complex has generated global recognition of the need for rapid and sensitive diagnosis and development of new treatments. The current study illustrates the isolation/identification of MTBC strains in specimens obtained from cows and humans by conventional and real-time polymerase chain reaction (RT-PCR) techniques. Further, the study assesses sensitivity to antituberculosis drugs in isolated MDR strains. Materials and Methods: A total of 1464 samples from cattle (1285 raw milk and 179 lymph node), and 149 human sputum samples, were collected from farms and abattoirs in Delta Egypt. Conventional methods (culture and Ziehl–Neelsen staining) were implemented as were RT-PCR using MTBC universal DNA. The effect of some antituberculosis drugs on obtained isolates was assayed using drug susceptibility proportion and qualitative suspension techniques. Results: The MBTC detection rate using the culture method was higher than for Ziehl–Neelsen staining; raw cow milk (2.56 vs. 1.63%), lymph nodes (51.59 vs. 48.04%), and human sputum (5.36 vs. 4.02%). A total of 135 isolates were obtained. Application of RT-PCR detected 138 isolates from the same set of samples. MBTC isolates were resistant to first-line antituberculosis drugs, such as pyrazinamide, isoniazid, rifampicin, and ethambutol by 78.5, 59.3, 40.7, and 31.8%, respectively, and could be highly resistant to kanamycin (82.3%) and amikacin (80.7%). However, isolates remained sensitive to ciprofloxacin (71.1%) and clarithromycin (73.3%) as second-line drugs. Conclusion: There is a growing risk for isolation of MDR-TB from raw milk and lymph nodes of field tuberculin positive cattle as well as sputum of veterinarians and workers existed in farms and abattoirs. PCR-based techniques have become the gold standard for the identification of mycobacterial species, showing high efficiency compared to bacteriological and microscopic examination. Application of the first- and second-line antituberculosis drugs in combination could counter the MDR-TB concern once infections are identified.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Matthias Merker ◽  
Nkongho F. Egbe ◽  
Yannick R. Ngangue ◽  
Comfort Vuchas ◽  
Thomas A. Kohl ◽  
...  

Abstract Background Determining factors affecting the transmission of rifampicin (RR) and multidrug-resistant (MDR) Mycobacterium tuberculosis complex strains under standardized tuberculosis (TB) treatment is key to control TB and prevent the evolution of drug resistance. Methods We combined bacterial whole genome sequencing (WGS) and epidemiological investigations for 37% (n = 195) of all RR/MDR-TB patients in Cameroon (2012–2015) to identify factors associated with recent transmission. Results Patients infected with a strain resistant to high-dose isoniazid, and ethambutol had 7.4 (95% CI 2.6–21.4), and 2.4 (95% CI 1.2–4.8) times increased odds of being in a WGS-cluster, a surrogate for recent transmission. Furthermore, age between 30 and 50 was positively correlated with recent transmission (adjusted OR 3.8, 95% CI 1.3–11.4). We found high drug-resistance proportions against three drugs used in the short standardized MDR-TB regimen in Cameroon, i.e. high-dose isoniazid (77.4%), ethambutol (56.9%), and pyrazinamide (43.1%). Virtually all strains were susceptible to fluoroquinolones, kanamycin, and clofazimine, and treatment outcomes were mostly favourable (87.5%). Conclusion Pre-existing resistance to high-dose isoniazid, and ethambutol is associated with recent transmission of RR/MDR strains in our study. A possible contributing factor for this observation is the absence of universal drug susceptibility testing in Cameroon, likely resulting in prolonged exposure of new RR/MDR-TB patients to sub-optimal or failing first-line drug regimens.


Sign in / Sign up

Export Citation Format

Share Document