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Robbins L, Balaram A, Dejneka S, McMahon M, Najibi Z, Pawlowicz P, Conrad WH. Heterologous production of the D-cycloserine intermediate O-acetyl-L-serine in a human type II pulmonary cell model. Sci Rep 2023; 13:8551. [PMID: 37237156 DOI: 10.1038/s41598-023-35632-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 05/21/2023] [Indexed: 05/28/2023] Open
Abstract
Tuberculosis (TB) is the second leading cause of death by a single infectious disease behind COVID-19. Despite a century of effort, the current TB vaccine does not effectively prevent pulmonary TB, promote herd immunity, or prevent transmission. Therefore, alternative approaches are needed. We seek to develop a cell therapy that produces an effective antibiotic in response to TB infection. D-cycloserine (D-CS) is a second-line antibiotic for TB that inhibits bacterial cell wall synthesis. We have determined D-CS to be the optimal candidate for anti-TB cell therapy due to its effectiveness against TB, relatively short biosynthetic pathway, and its low-resistance incidence. The first committed step towards D-CS synthesis is catalyzed by the L-serine-O-acetyltransferase (DcsE) which converts L-serine and acetyl-CoA to O-acetyl-L-serine (L-OAS). To test if the D-CS pathway could be an effective prophylaxis for TB, we endeavored to express functional DcsE in A549 cells as a human pulmonary model. We observed DcsE-FLAG-GFP expression using fluorescence microscopy. DcsE purified from A549 cells catalyzed the synthesis of L-OAS as observed by HPLC-MS. Therefore, human cells synthesize functional DcsE capable of converting L-serine and acetyl-CoA to L-OAS demonstrating the first step towards D-CS production in human cells.
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Affiliation(s)
- Laurel Robbins
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - Ariane Balaram
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - Stefanie Dejneka
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - Matthew McMahon
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - Zarina Najibi
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - Peter Pawlowicz
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA
| | - William H Conrad
- Department of Chemistry and Biochemistry and Molecular Biology Program, Lake Forest College, Lake Forest, USA.
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Mamada SS, Nainu F, Masyita A, Frediansyah A, Utami RN, Salampe M, Emran TB, Lima CMG, Chopra H, Simal-Gandara J. Marine Macrolides to Tackle Antimicrobial Resistance of Mycobacterium tuberculosis. Mar Drugs 2022; 20:691. [PMID: 36355013 PMCID: PMC9697125 DOI: 10.3390/md20110691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 09/01/2023] Open
Abstract
Tuberculosis has become a major health problem globally. This is worsened by the emergence of resistant strains of Mycobacterium tuberculosis showing ability to evade the effectiveness of the current antimycobacterial therapies. Therefore, the efforts carried out to explore new entities from many sources, including marine, are critical. This review summarizes several marine-derived macrolides that show promising activity against M. tuberculosis. We also provide information regarding the biosynthetic processes of marine macrolides, including the challenges that are usually experienced in this process. As most of the studies reporting the antimycobacterial activities of the listed marine macrolides are based on in vitro studies, the future direction should consider expanding the trials to in vivo and clinical trials. In addition, in silico studies should also be explored for a quick screening on marine macrolides with potent activities against mycobacterial infection. To sum up, macrolides derived from marine organisms might become therapeutical options for tackling antimycobacterial resistance of M. tuberculosis.
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Affiliation(s)
- Sukamto S. Mamada
- Department of Pharmacy, Faculty of Pharmacy, Hasanuddin University, Makassar 90245, Indonesia
| | - Firzan Nainu
- Department of Pharmacy, Faculty of Pharmacy, Hasanuddin University, Makassar 90245, Indonesia
| | - Ayu Masyita
- Department of Pharmaceutical Science and Technology, Faculty of Pharmacy, Hasanuddin University, Makassar 90245, Indonesia
- Research Center for Vaccine and Drugs, Research Organization for Health, National Research and Innovation Agency (BRIN), Tangerang Selatan 15318, Indonesia
| | - Andri Frediansyah
- Research Center for Food Technology and Processing, National Research and Innovation Agency (BRIN), Yogyakarta 55861, Indonesia
| | - Rifka Nurul Utami
- Department of Pharmaceutical Science and Technology, Faculty of Pharmacy, Hasanuddin University, Makassar 90245, Indonesia
- Institute of Pharmaceutical Science, King’s College London, London SE1 9NH, UK
| | | | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong 4381, Bangladesh
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | | | - Hitesh Chopra
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Jesus Simal-Gandara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain
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Mycobacterium simiae Isolates Subtypes and Molecular Drug Susceptibility in Iran. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2022. [DOI: 10.5812/archcid-127866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: Despite the clinical and epidemiological importance of Mycobacterium simiae worldwide, including in Iran, there is no clear and effective treatment regimen for M. simiae and its different subtypes. Objectives: Concerning the superiority of molecular approaches, this study aims to identify the common M. simiae subtypes submitted to the National Reference Tuberculosis (TB) Laboratory of Iran and study the presence of drug resistance by molecular detection methods. Methods: We included sputum samples with M. simiae confirmation submitted to the National Reference TB Laboratory of Iran from May 2014 to May 2016. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used for drug susceptibility testing (DST). Results: Among 7200 TB suspected patients, a total of 60 M. simiae cases belonging to subtype I were identified. All the included clinical isolates met the American Thoracic Society (ATS) and Infectious Diseases Society of America (IDSA) diagnostic criteria and were considered the disease’s causative pathogen. Males (58.33%), elderly (68.54%), and patients with a history of TB (51.42%) were shown to be more prone to infection with the disease. All clinical isolates of M. simiae were resistant to rifampin (RIF) and isoniazid (INH). Amikacin/kanamycin (AMK/KAN) and ciprofloxacin (CIP) susceptibility was found to be 91.66% and 88.33%, respectively. Conclusions: Subtype I was exclusively identified among M. simiae patients in Iran. Molecular detection of drug resistance suggests that amikacin/kanamycin and ciprofloxacin could be used to treat patients infected with M. simiae subtype I.
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Sheikh BA, Bhat BA, Mehraj U, Mir W, Hamadani S, Mir MA. Development of New Therapeutics to Meet the Current Challenge of Drug Resistant Tuberculosis. Curr Pharm Biotechnol 2021; 22:480-500. [PMID: 32600226 DOI: 10.2174/1389201021666200628021702] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/01/2020] [Accepted: 05/13/2020] [Indexed: 11/22/2022]
Abstract
Tuberculosis (TB) is a prominent infective disease and a major reason of mortality/ morbidity globally. Mycobacterium tuberculosis causes a long-lasting latent infection in a significant proportion of human population. The increasing burden of tuberculosis is mainly caused due to multi drug-resistance. The failure of conventional treatment has been observed in large number of cases. Drugs that are used to treat extensively drug-resistant tuberculosis are expensive, have limited efficacy, and have more side effects for a longer duration of time and are often associated with poor prognosis. To regulate the emergence of multidrug resistant tuberculosis, extensively drug-resistant tuberculosis and totally drug resistant tuberculosis, efforts are being made to understand the genetic/molecular basis of target drug delivery and mechanisms of drug resistance. Understanding the molecular approaches and pathology of Mycobacterium tuberculosis through whole genome sequencing may further help in the improvement of new therapeutics to meet the current challenge of global health. Understanding cellular mechanisms that trigger resistance to Mycobacterium tuberculosis infection may expose immune associates of protection, which could be an important way for vaccine development, diagnostics, and novel host-directed therapeutic strategies. The recent development of new drugs and combinational therapies for drug-resistant tuberculosis through major collaboration between industry, donors, and academia gives an improved hope to overcome the challenges in tuberculosis treatment. In this review article, an attempt was made to highlight the new developments of drug resistance to the conventional drugs and the recent progress in the development of new therapeutics for the treatment of drugresistant and non-resistant cases.
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Affiliation(s)
- Bashir A Sheikh
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
| | - Basharat A Bhat
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
| | - Umar Mehraj
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
| | - Wajahat Mir
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
| | - Suhail Hamadani
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
| | - Manzoor A Mir
- Department of Bioresources, School of Biological Sciences, University of Kashmir, Srinagar-190006, India
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Ramakrishna V, Singh PK, Prakash S, Jain A. Second Line Injectable Drug Resistance and Associated Genetic Mutations in Newly Diagnosed Cases of Multidrug-Resistant Tuberculosis. Microb Drug Resist 2020; 26:971-975. [PMID: 32101083 DOI: 10.1089/mdr.2019.0215] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Aim: To investigate the phenotypic and genotypic profile of multidrug-resistant (MDR) Mycobacterium tuberculosis (MTB) clinical isolates with reference to second-line injectable drugs (SLIDs). Methods: A total of 110 MTB isolates, recovered consecutively from confirmed MDR-TB patients between March and June 2016, were included in this study. Phenotypic drug susceptibility testing against SLIDs (Kanamycin, Amikacin, and Capreomycin) and Ofloxacin (OFX) was performed using the MGIT 960 system. For genotypic analysis, SLID/(s) resistant (n = 13) and susceptible isolates (n = 26) were subjected to PCR and DNA sequencing for rrs, eis (promoter region), and tlyA loci of MTB. Furthermore, the identified genetic mutations were analyzed with respect to its significance in detecting phenotypic resistance. Result: Among the 110 analyzed isolates, phenotypic resistance to OFX, SLIDs, and to both was 59.1%, 11.8%, and 10.0%, respectively. Out of a total 13 SLID/(s) resistant isolates, 10 had mutations (including two novel mutations) in one or more of the targeted genes. Only one SLID susceptible MTB isolate showed mutation in the targeted region. In SLID resistant isolates, most frequent mutation detected was C-12T under eis promoter region (46.1%). Conclusion: Mutations in rrs, eis, and tly A loci together are important in predicting SLID resistance in MTB isolates. Future molecular epidemiology studies are needed to have more insight into frequency and clinical relevance of novel mutations identified in this study.
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Affiliation(s)
- Vangala Ramakrishna
- Department of Microbiology, King George's Medical University, Lucknow, India
| | - Pravin Kumar Singh
- Department of Microbiology, King George's Medical University, Lucknow, India
| | - Shantanu Prakash
- Department of Microbiology, King George's Medical University, Lucknow, India
| | - Amita Jain
- Department of Microbiology, King George's Medical University, Lucknow, India
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Structural Bases for the Fitness Cost of the Antibiotic-Resistance and Lethal Mutations at Position 1408 of 16S rRNA. Molecules 2019; 25:molecules25010159. [PMID: 31906077 PMCID: PMC6983231 DOI: 10.3390/molecules25010159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/29/2019] [Accepted: 12/29/2019] [Indexed: 02/04/2023] Open
Abstract
To understand a structural basis for the fitness cost of the A1408G antibiotic-resistance mutation in the ribosomal A-site RNA, we have determined crystal structures of its A1408C and A1408U lethal mutants, and made comparison with previously solved structures of the wild type and the antibiotic-resistant mutant. The A-site RNA containing an asymmetric internal loop functions as a molecular switch to discriminate a single cognate tRNA from several near-cognate tRNAs by its conformational ON/OFF switching. Overall structures of the “off” states of the A1408C/U lethal mutants are very similar to those of the wild type and the A1408G antibiotic-resistant mutant. However, significant differences are found in local base stacking interactions including the functionally important A1492 and A1493 residues. In the wild type and the A1408G antibiotic-resistant mutant “off” states, both adenines are exposed to the solvent region. On the other hand, one of the corresponding adenines of the lethal A1408C/U mutants stay deeply inside their A-site helices by forming a purine-pyrimidine AoC or A-U base pair and is sandwiched between the upper and lower bases. Therefore, the ON/OFF switching might unfavorably occur in the lethal mutants compared to the wild type and the A1408G antibiotic-resistant mutant. It is probable that bacteria manage to acquire antibiotic resistance without losing the function of the A-site molecular switch by mutating the position 1408 only from A to G, but not to pyrimidine base C or U.
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Cruz JN, Costa JFS, Khayat AS, Kuca K, Barros CAL, Neto AMJC. Molecular dynamics simulation and binding free energy studies of novel leads belonging to the benzofuran class inhibitors of Mycobacterium tuberculosis Polyketide Synthase 13. J Biomol Struct Dyn 2018; 37:1616-1627. [PMID: 29633908 DOI: 10.1080/07391102.2018.1462734] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In this work, the binding mechanism of new Polyketide Synthase 13 (Pks13) inhibitors has been studied through molecular dynamics simulation and free energy calculations. The drug Tam1 and its analogs, belonging to the benzofuran class, were submitted to 100 ns simulations, and according to the results obtained for root mean square deviation, all the simulations converged from approximately 30 ns. For the analysis of backbone flotation, the root mean square fluctuations were plotted for the Cα atoms; analysis revealed that the greatest fluctuation occurred in the residues that are part of the protein lid domain. The binding free energy value (ΔGbind) obtained for the Tam16 lead molecule was of -51.43 kcal/mol. When comparing this result with the ΔGbind values for the remaining analogs, the drug Tam16 was found to be the highest ranked: this result is in agreement with the experimental results obtained by Aggarwal and collaborators, where it was verified that the IC50 for Tam16 is the smallest necessary to inhibit the Pks13 (IC50 = 0.19 μM). The energy decomposition analysis suggested that the residues which most interact with inhibitors are: Ser1636, Tyr1637, Asn1640, Ala1667, Phe1670, and Tyr1674, from which the greatest energy contribution to Phe1670 was particularly notable. For the lead molecule Tam16, a hydrogen bond with the hydroxyl of the phenol not observed in the other analogs induced a more stable molecular structure. Aggarwal and colleagues reported this hydrogen bonding as being responsible for the stability of the molecule, optimizing its physic-chemical, toxicological, and pharmacokinetic properties.
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Key Words
- CNPq, National Council for Scientific and Technological Development
- CoA, coenzyme A
- FAS, fatty acid synthase
- GAFF, general amber force field
- GB, generalized born
- HB, hydrogen bonds
- INH, isoniazid
- KatG, catalase-peroxidase
- MD, molecular dynamics
- MDR, multi-drug resistant
- MM/GBSA, molecular mechanics/generalized-born surface area
- NAD, nicotinamide adenine dinucleotide
- NS, nanoseconds
- PCA, acyl carrier protein
- Pks13
- Pks13, polyketide synthase 13
- RESP, restrained electrostatic potential
- RMSD, root mean square deviation
- RMSF, root mean square fluctuations
- TB, tuberculosis
- TE, C-terminal thioesterase
- XDR, extensively drug resistant
- benzofuran
- free energy
- inhibitors
- molecular dynamics
- Δ internal energy
- Δ, Van Der Waals contributions
- Δ, electrostatic contribution
- Δ, electrostatic contributions
- Δ, energy of desolvation
- Δ, energy of the molecular mechanics
- Δ, non-polar contributions
- Δ, polar contributions
- Δ, polar solvation contribution
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Affiliation(s)
- Jorddy N Cruz
- a Laboratory of Preparation and Computation of Nanomaterials , Federal University of Pará , CP 479, 66075-110 Belém , PA , Brazil
| | - José F S Costa
- a Laboratory of Preparation and Computation of Nanomaterials , Federal University of Pará , CP 479, 66075-110 Belém , PA , Brazil
| | - André S Khayat
- b Oncology Research Center , Federal University of Pará , CP 479, 6675-105 Belém , PA , Brazil
| | - Kamil Kuca
- c Biomedical Research Center , University Hospital Hradec Kralove , Sokolska 581, 500 05 Hradec Kralove , Czech Republic
| | - Carlos A L Barros
- d Department of Pharmacy , Federal University of Pará , CP 479, 66050-160 Belém , PA , Brazil
| | - A M J C Neto
- a Laboratory of Preparation and Computation of Nanomaterials , Federal University of Pará , CP 479, 66075-110 Belém , PA , Brazil
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Kerry RG, Gouda S, Sil B, Das G, Shin HS, Ghodake G, Patra JK. Cure of tuberculosis using nanotechnology: An overview. J Microbiol 2018; 56:287-299. [PMID: 29721825 DOI: 10.1007/s12275-018-7414-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/04/2018] [Accepted: 01/04/2018] [Indexed: 02/03/2023]
Abstract
Mycobacterium tuberculosis is the causative agent of tuberculosis (TB), a major health issue of the present era. The bacterium inhabits the host macrophage and other immune cells where it modulates the lysosome trafficking protein, hinders the formation of phagolysosome, and blocks the TNF receptor-dependent apoptosis of host macrophage/monocytes. Other limitations such as resistance to and low bioavailability and bio-distribution of conventional drugs aid to their high virulence and human mortality. This review highlights the use of nanotechnology-based approaches for drug formulation and delivery which could open new avenues to limit the pathogenicity of tuberculosis. Moreover phytochemicals, such as alkaloids, phenols, saponins, steroids, tannins, and terpenoids, extracted from terrestrial plants and mangroves seem promising against M. tuberculosis through different molecular mechanisms. Further understanding of the genomics and proteomics of this pathogenic microbe could also help overcome various research gaps in the path of developing a suitable therapy against tuberculosis.
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Affiliation(s)
- Rout George Kerry
- Department of Biotechnology, AMIT College, Khurda, 752057, Odisha, India
| | - Sushanto Gouda
- Amity Institute of Wildlife Science, Amity University, Noida, 201313, Uttar Pradesh, India
| | - Bikram Sil
- Department of Biotechnology, AMIT College, Khurda, 752057, Odisha, India
| | - Gitishree Das
- Research Institute of Biotechnology & Medical Converged Science, Dongguk University-Seoul, Goyang, 10326, Republic of Korea
| | - Han-Seung Shin
- Department of Food Science and Biotechnology, Dongguk University-Seoul, Goyang, 10326, Republic of Korea.
| | - Gajanan Ghodake
- Department of Biological and Environmental Science, College of Life Science and Biotechnology, Dongguk University-Seoul, Goyang, 10326, Republic of Korea
| | - Jayanta Kumar Patra
- Research Institute of Biotechnology & Medical Converged Science, Dongguk University-Seoul, Goyang, 10326, Republic of Korea.
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Dookie N, Rambaran S, Padayatchi N, Mahomed S, Naidoo K. Evolution of drug resistance in Mycobacterium tuberculosis: a review on the molecular determinants of resistance and implications for personalized care. J Antimicrob Chemother 2018; 73:1138-1151. [PMID: 29360989 PMCID: PMC5909630 DOI: 10.1093/jac/dkx506] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Drug-resistant TB (DR-TB) remains a significant challenge in TB treatment and control programmes worldwide. Advances in sequencing technology have significantly increased our understanding of the mechanisms of resistance to anti-TB drugs. This review provides an update on advances in our understanding of drug resistance mechanisms to new, existing drugs and repurposed agents. Recent advances in WGS technology hold promise as a tool for rapid diagnosis and clinical management of TB. Although the standard approach to WGS of Mycobacterium tuberculosis is slow due to the requirement for organism culture, recent attempts to sequence directly from clinical specimens have improved the potential to diagnose and detect resistance within days. The introduction of new databases may be helpful, such as the Relational Sequencing TB Data Platform, which contains a collection of whole-genome sequences highlighting key drug resistance mutations and clinical outcomes. Taken together, these advances will help devise better molecular diagnostics for more effective DR-TB management enabling personalized treatment, and will facilitate the development of new drugs aimed at improving outcomes of patients with this disease.
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Affiliation(s)
- Navisha Dookie
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Santhuri Rambaran
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Nesri Padayatchi
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
- South African Medical Research Council (SAMRC) - CAPRISA HIV-TB Pathogenesis and Treatment Research Unit, Durban, South Africa
| | - Sharana Mahomed
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Kogieleum Naidoo
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
- South African Medical Research Council (SAMRC) - CAPRISA HIV-TB Pathogenesis and Treatment Research Unit, Durban, South Africa
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In Vitro Susceptibility of Mycobacterium tuberculosis to Amikacin, Kanamycin, and Capreomycin. Antimicrob Agents Chemother 2018; 62:AAC.01724-17. [PMID: 29311078 DOI: 10.1128/aac.01724-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/13/2017] [Indexed: 11/20/2022] Open
Abstract
Amikacin, kanamycin, and capreomycin are among the most important second-line drugs for multidrug-resistant tuberculosis. Although amikacin and kanamycin are administered at the same dose and show the same pharmacokinetics, they have different WHO breakpoints, suggesting that the two drugs have different MICs. The aim of this study was to investigate possible differences in MICs between the aminoglycosides and capreomycin. Using the direct concentration method, a range of concentrations of amikacin, kanamycin, and capreomycin (0.25, 0.50, 1.0, 2.0, 4.0, 8.0, 16.0, 32.0, and 64.0 mg/liter) were tested against 57 clinical Mycobacterium tuberculosis strains. The 7H10 agar plates were examined for mycobacterial growth after 14 days. At 2 mg/liter, 48 strains (84%) were inhibited by amikacin and only 5 strains (9%) were inhibited by kanamycin (P < 0.05, Wilcoxon signed-rank test). The median MICs of amikacin, kanamycin, and capreomycin were 2, 4, and 8 mg/liter, respectively. No difference in amikacin, kanamycin, and capreomycin MIC distributions was observed between multidrug-resistant strains and fully susceptible strains. The results indicate that amikacin is more active than kanamycin and capreomycin against M. tuberculosis with the absolute concentration method. Determination of the impact of this difference on clinical outcomes in daily practice requires a prospective study, including pharmacokinetic and pharmacodynamic evaluations.
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Abstract
The global epidemic of multidrug-resistant tuberculosis (MDR-TB) caused by Mycobacterium tuberculosis strains resistant to at least isoniazid and rifampin was recently reported as larger than previously estimated, with at least 580,000 new cases reported in 2015. Extensively drug-resistant tuberculosis (XDR-TB), MDR-TB with additional resistance to a second-line fluoroquinolone and injectable, continues to account for nearly 10% of MDR cases globally. Cases in India, China, and the Russian Federation account for >45% of the cases of MDR-TB. Molecular testing helps identify MDR more quickly, and treatment options have expanded across the globe. Despite this, only 20% are in treatment, and treatment is challenging due to the toxicity of medications and the long duration. In 2016 the World Health Organization updated guidelines for the treatment of MDR-TB. A new short-course regimen is an option for those who qualify. Five effective drugs, including pyrazinamide (PZA) when possible, are recommended during the initial treatment phase and four drugs thereafter. Revised drug classifications include the use of linezolid and clofazimine as key second-line drugs and the option to use bedaquiline and delamanid to complete a five-drug regimen when needed due to poor medication tolerance or extensive resistance. Despite multiple drugs and long-duration treatment regimens, the outcomes for MDR and especially XDR-TB are much worse than for drug-susceptible disease. Better management of toxicity, prevention of transmission, and identification and appropriate management of infected contacts are important challenges for the future.
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Reduced Chance of Hearing Loss Associated with Therapeutic Drug Monitoring of Aminoglycosides in the Treatment of Multidrug-Resistant Tuberculosis. Antimicrob Agents Chemother 2017; 61:AAC.01400-16. [PMID: 28069654 DOI: 10.1128/aac.01400-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 12/04/2016] [Indexed: 11/20/2022] Open
Abstract
Hearing loss and nephrotoxicity are associated with prolonged treatment duration and higher dosage of amikacin and kanamycin. In our tuberculosis center, we used therapeutic drug monitoring (TDM) targeting preset pharmacokinetic/pharmacodynamic (PK/PD) surrogate endpoints in an attempt to maintain efficacy while preventing (oto)toxicity. To evaluate this strategy, we retrospectively evaluated medical charts of tuberculosis (TB) patients treated with amikacin or kanamycin in the period from 2000 to 2012. Patients with culture-confirmed multiresistant or extensively drug-resistant tuberculosis (MDR/XDR-TB) receiving amikacin or kanamycin as part of their TB treatment for at least 3 days were eligible for inclusion in this retrospective study. Clinical data, including maximum concentration (Cmax), Cmin, and audiometry data, were extracted from the patients' medical charts. A total of 80 patients met the inclusion criteria. The mean weighted Cmax/MIC ratios obtained from 57 patients were 31.2 for amikacin and 12.3 for kanamycin. The extent of hearing loss was limited and correlated with the cumulative drug dose per kg of body weight during daily administration. At follow-up, 35 (67.3%) of all patients had successful outcome; there were no relapses. At a median dose of 6.5 mg/kg, a correlation was found between the dose per kg of body weight during daily dosing and the extent of hearing loss in dB at 8,000 Hz. These findings suggest that the efficacy at this lower dosage is maintained with limited toxicity. A randomized controlled trial should provide final proof of the safety and efficacy of TDM-guided use of aminoglycosides in MDR-TB treatment.
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Molecular Investigation of Resistance to Second-Line Injectable Drugs in Multidrug-Resistant Clinical Isolates of Mycobacterium tuberculosis in France. Antimicrob Agents Chemother 2017; 61:AAC.01299-16. [PMID: 27895017 DOI: 10.1128/aac.01299-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/03/2016] [Indexed: 12/14/2022] Open
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).
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Bang D, Andersen SR, Vasiliauskienė E, Rasmussen EM. Performance of the GenoType MTBDRplus assay (v2.0) and a new extended GenoType MTBDRsl assay (v2.0) for the molecular detection of multi- and extensively drug-resistant Mycobacterium tuberculosis on isolates primarily from Lithuania. Diagn Microbiol Infect Dis 2016; 86:377-381. [PMID: 27641092 DOI: 10.1016/j.diagmicrobio.2016.08.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/07/2016] [Accepted: 08/28/2016] [Indexed: 11/15/2022]
Abstract
The emergence of extensively drug-resistant tuberculosis (XDR-TB) hampers infection control. To assess the performance of an extended rapid novel molecular analysis for the detection of resistance conferring mutations to fluoroquinolones (gyrA, gyrB genes) and aminoglycosides/cyclic peptides (16S rRNA rrs gene, eis promotor region) compared to phenotypic susceptibility and sequencing, 43 multidrug-resistant (MDR) and 10 susceptible clinical isolates were analyzed. Results were compared to a previous version. Molecular rifampin (rpoB gene) and isoniazid (katG gene, inhA promotor region) resistance was also analyzed. XDR-TB was confirmed in 13 (30%) MDR isolates. Molecular resistance was detected in 91% ofloxacin-, 83% aminoglycoside/cyclic peptide- and 100% kanamycin-resistant isolates. In conclusion, the novel assay is a useful supplement to phenotypic susceptibility testing in determining the presence of XDR-TB. Molecular kanamycin resistance detection was immensely improved compared to the previous version. Aminoglycoside/cyclic peptide susceptible isolates revealed eis promotor region resistance in 29%, reflecting low-level kanamycin susceptibility challenges.
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Affiliation(s)
- Didi Bang
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark; Microbiological Diagnostics & Virology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark.
| | - Siri Rytcher Andersen
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark
| | - Edita Vasiliauskienė
- Infectious Diseases and Tuberculosis Hospital, Vilnius University Hospital Santariskiu Klinikos, Lithuania; Department of Physiology, Biochemistry & Laboratory Medicine, Faculty of Medicine, Vilnius University, Lithuania
| | - Erik Michael Rasmussen
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark
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Gualano G, Capone S, Matteelli A, Palmieri F. New Antituberculosis Drugs: From Clinical Trial to Programmatic Use. Infect Dis Rep 2016; 8:6569. [PMID: 27403268 PMCID: PMC4927937 DOI: 10.4081/idr.2016.6569] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 04/29/2016] [Indexed: 01/05/2023] Open
Abstract
Treatment of multidrug-resistant tuberculosis (MDR-TB) cases is challenging because it relies on second-line drugs that are less potent and more toxic than those used in the clinical management of drug-susceptible TB. Moreover, treatment outcomes for MDR-TB are generally poor compared to drug sensitive disease, highlighting the need for of new drugs. For the first time in more than 50 years, two new anti-TB drugs were approved and released. Bedaquiline is a first-in-class diarylquinoline compound that showed durable culture conversion at 24 weeks in phase IIb trials. Delamanid is the first drug of the nitroimidazole class to enter clinical practice. Similarly to bedaquiline results of phase IIb studies showed increased sputum-culture conversion at 2 months and better final treatment outcomes in patients with MDR-TB. Among repurposed drugs linezolid and carbapenems may represent a valuable drug to treat cases of MDR and extensively drug-resistant TB. The recommended regimen for MDR-TB is the combination of at least four drugs to which M. tuberculosis is likely to be susceptible for the duration of 20 months. Drugs are chosen with a stepwise selection process through five groups on the basis of efficacy, safety, and cost. Clinical phase III trials on new regimen are ongoing that could prove transformative against MDR-TB, by being shorter (six months), simpler (an all-oral regimen) and safer than current standard therapy. It is fundamental that the adoption of the new drugs is done responsibly to avoid inappropriate use. Concentration of in-patient MDR-TB treatment in specialized centers could be considered in countries with low numbers of cases in order to provide appropriate clinical case management and to prevent emergence of drug resistance.
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Affiliation(s)
- Gina Gualano
- Respiratory Infectious Diseases Unit, National Institute for Infectious Diseases L. Spallanzani , Rome
| | - Susanna Capone
- Department of Infectious and Tropical Diseases, WHO Collaborating Centre for TB/HIV and TB Elimination, University of Brescia , Italy
| | - Alberto Matteelli
- Department of Infectious and Tropical Diseases, WHO Collaborating Centre for TB/HIV and TB Elimination, University of Brescia , Italy
| | - Fabrizio Palmieri
- Respiratory Infectious Diseases Unit, National Institute for Infectious Diseases L. Spallanzani , Rome
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Yu X, Gu Y, Jiang G, Ma Y, Zhao L, Sun Z, Jain P, O'Donnell M, Larsen M, Jacobs WR, Huang H. Evaluation of a High-Intensity Green Fluorescent Protein Fluorophage Method for Drug- Resistance Diagnosis in Tuberculosis for Isoniazid, Rifampin, and Streptomycin. Front Microbiol 2016; 7:922. [PMID: 27379052 PMCID: PMC4911409 DOI: 10.3389/fmicb.2016.00922] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 05/31/2016] [Indexed: 11/30/2022] Open
Abstract
A novel method for detecting drug resistance in Mycobacterium tuberculosis using mycobacteriophage Φ (2) GFP10 was evaluated with clinical isolates. The phage facilitates microscopic fluorescence detection due to the high expression of green fluorescence protein which also simplifies the operative protocol as well. A total of 128 clinical isolates were tested by the phage assay for isoniazid (INH), rifampin (RIF), and streptomycin (STR) resistance while conventional drug susceptibility test, by MGIT960, was used as reference. The sensitivities of Φ (2) GFP10 assay for INH, RIF, and STR resistance detection were 100, 98.2, and 89.3%, respectively while their specificities were 85.1, 98.6, and 95.8%, respectively. The agreement between phage and conventional assay for detecting INH, RIF, and STR resistance was 92.2, 98.4, and 93.0%, respectively. The Φ (2) GFP10-phage results could be available in 2 days for RIF and STR, while it takes 3 days for INH, with an estimated cost of less than $2 to test all the three antibiotics. The Φ (2) GFP10-phage method has the potential to be a valuable, rapid and economical screening method for detecting drug-resistant tuberculosis.
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Affiliation(s)
- Xia Yu
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Yunting Gu
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Guanglu Jiang
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Yifeng Ma
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Liping Zhao
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Zhaogang Sun
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
| | - Paras Jain
- Department of Microbiology and Immunology, Albert Einstein College of MedicineBronx, NY, USA
| | - Max O'Donnell
- Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University Medical CenterNew York, NY, USA
- Department of Epidemiology, Mailman School of Public Health, Columbia University Medical CenterNew York, NY, USA
| | - Michelle Larsen
- Department of Microbiology and Immunology, Albert Einstein College of MedicineBronx, NY, USA
| | - William R. Jacobs
- Department of Microbiology and Immunology, Albert Einstein College of MedicineBronx, NY, USA
- Howard Hughes Medical InstituteChevy Chase, MD, USA
| | - Hairong Huang
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Institute, Capital Medical UniversityBeijing, China
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Wilson JW, Tsukayama DT. Extensively Drug-Resistant Tuberculosis: Principles of Resistance, Diagnosis, and Management. Mayo Clin Proc 2016; 91:482-95. [PMID: 26906649 DOI: 10.1016/j.mayocp.2016.01.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/20/2016] [Accepted: 01/21/2016] [Indexed: 12/14/2022]
Abstract
Extensively drug-resistant (XDR) tuberculosis (TB) is an unfortunate by-product of mankind's medical and pharmaceutical ingenuity during the past 60 years. Although new drug developments have enabled TB to be more readily curable, inappropriate TB management has led to the emergence of drug-resistant disease. Extensively drug-resistant TB describes Mycobacterium tuberculosis that is collectively resistant to isoniazid, rifampin, a fluoroquinolone, and an injectable agent. It proliferates when established case management and infection control procedures are not followed. Optimized treatment outcomes necessitate time-sensitive diagnoses, along with expanded combinations and prolonged durations of antimicrobial drug therapy. The challenges to public health institutions are immense and most noteworthy in underresourced communities and in patients coinfected with human immunodeficiency virus. A comprehensive and multidisciplinary case management approach is required to optimize outcomes. We review the principles of TB drug resistance and the risk factors, diagnosis, and managerial approaches for extensively drug-resistant TB. Treatment outcomes, cost, and unresolved medical issues are also discussed.
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Affiliation(s)
- John W Wilson
- Department of Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, MN.
| | - Dean T Tsukayama
- Division of Infectious Diseases and Internal Medicine, University of Minnesota, Hennepin County Medical Center, Minneapolis, MN
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Truitt AR, Choi BE, Li J, Soto AM. Effect of Mutations on the Binding of Kanamycin-B to RNA Hairpins Derived from the Mycobacterium tuberculosis Ribosomal A-Site. Biochemistry 2015; 54:7425-37. [PMID: 26560864 DOI: 10.1021/acs.biochem.5b00710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kanamycin is an aminoglycoside antibiotic used in the treatment of drug-resistant tuberculosis. Mutations at the rRNA A-site have been associated with kanamycin resistance in Mycobacterium tuberculosis clinical isolates. Understanding the effect of these mutations on the conformation of the M. tuberculosis A-site is critical for understanding the mechanisms of antibiotic resistance in M. tuberculosis. In this work, we have studied RNA hairpins derived from the M. tuberculosis A-site, the wild type and three mutants at the following positions (M. tuberculosis/Escherichia coli numbering): A1400/1408 → G, C1401/1409 → U, and the double mutant G1483/1491 C1401/1409 → UA. Specifically, we used circular dichroism, ultraviolet spectroscopy, and fluorescence spectroscopy to characterize the conformation, stability, and binding affinity of kanamycin-B and other aminoglycoside antibiotics for these RNA hairpins. Our results show that the mutations affect the conformation of the decoding site, with the mutations at position 1401/1409 resulting in significant destabilizations. Interestingly, the mutants bind paromomycin with weaker affinity than the wild type, but they bind kanamycin-B with similar affinity than the wild type. The results suggest that the presence of mutations does not prevent kanamycin-B from binding. Instead, kanamycin may promote different interactions with a third partner in the mutants compared to the wild type. Furthermore, our results with longer and shorter hairpins suggest that the region of the A-site that varies among organisms may have modulating effects on the binding and interactions of the A-site.
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Affiliation(s)
- Amber R Truitt
- Department of Chemistry and ‡Molecular Biology, Biochemistry and Bioinformatics Program, Towson University , 8000 York Road, Towson, Maryland 21252, United States
| | - Bok-Eum Choi
- Department of Chemistry and ‡Molecular Biology, Biochemistry and Bioinformatics Program, Towson University , 8000 York Road, Towson, Maryland 21252, United States
| | - Jenny Li
- Department of Chemistry and ‡Molecular Biology, Biochemistry and Bioinformatics Program, Towson University , 8000 York Road, Towson, Maryland 21252, United States
| | - Ana Maria Soto
- Department of Chemistry and ‡Molecular Biology, Biochemistry and Bioinformatics Program, Towson University , 8000 York Road, Towson, Maryland 21252, United States
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Casey CL, Hernandez SM, Yabsley MJ, Smith KF, Sanchez S. The carriage of antibiotic resistance by enteric bacteria from imported tokay geckos (Gekko gecko) destined for the pet trade. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 505:299-305. [PMID: 25461031 DOI: 10.1016/j.scitotenv.2014.09.102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/26/2014] [Accepted: 09/29/2014] [Indexed: 06/04/2023]
Abstract
The emergence of antibiotic-resistant bacteria is a growing public health concern and has serious implications for both human and veterinary medicine. The nature of the global economy encourages the movement of humans, livestock, produce, and wildlife, as well as their potentially antibiotic-resistant bacteria, across international borders. Humans and livestock can be reservoirs for antibiotic-resistant bacteria; however, little is known about the prevalence of antibiotic-resistant bacteria harbored by wildlife and, to our knowledge, limited data has been reported for wild-caught reptiles that were specifically collected for the pet trade. In the current study, we examined the antibiotic resistance of lactose-positive Enterobacteriaceae isolates from wild-caught Tokay geckos (Gekko gecko) imported from Indonesia for use in the pet trade. In addition, we proposed that the conditions under which wild animals are captured, transported, and handled might affect the shedding or fecal prevalence of antibiotic resistance. In particular we were interested in the effects of density; to address this, we experimentally modified densities of geckos after import and documented changes in antibiotic resistance patterns. The commensal enteric bacteria from Tokay geckos (G. gecko) imported for the pet trade displayed resistance against some antibiotics including: ampicillin, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, kanamycin and tetracycline. There was no significant difference in the prevalence of antibiotic-resistant bacteria after experimentally mimicking potentially stressful transportation conditions reptiles experience prior to purchase. There were, however, some interesting trends observed when comparing Tokay geckos housed individually and those housed in groups. Understanding the prevalence of antibiotic resistant commensal enteric flora from common pet reptiles is paramount because of the potential for humans exposed to these animals to acquire antibiotic-resistant bacteria and the potential for released pets to disseminate these bacteria to native wildlife.
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Affiliation(s)
- Christine L Casey
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, United States
| | - Sonia M Hernandez
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, United States; Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, United States.
| | - Michael J Yabsley
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, United States; Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, United States
| | - Katherine F Smith
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, United States
| | - Susan Sanchez
- The Athens Veterinary Diagnostic Laboratory, Athens, GA 30602, United States; The Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, United States
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20
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Bauskenieks M, Pole I, Skenders G, Jansone I, Broka L, Nodieva A, Ozere I, Kalvisa A, Ranka R, Baumanis V. Genotypic and phenotypic characteristics of aminoglycoside-resistant Mycobacterium tuberculosis isolates in Latvia. Diagn Microbiol Infect Dis 2014; 81:177-82. [PMID: 25557624 DOI: 10.1016/j.diagmicrobio.2014.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 12/03/2014] [Accepted: 12/10/2014] [Indexed: 10/24/2022]
Abstract
Mutations causing resistance to aminoglycosides, such as kanamycin (KAN), amikacin (AMK), and streptomycin, are not completely understood. In this study, polymorphisms of aminoglycoside resistance influencing genes such as rrs, eis, rpsL, and gidB in 41 drug-resistant and 17 pan-sensitive Mycobacterium tuberculosis clinical isolates in Latvia were analyzed. Mutation A1400G in rrs gene was detected in 92% isolates with high resistance level to KAN and diverse MIC level to AMK. Mutations in promoter region of eis were detected in 80% isolates with low-level MIC of KAN. The association of K43R mutation in rpsL gene, a mutation in the rrs gene at position 513, and various polymorphisms in gidB gene with distinct genetic lineages of M. tuberculosis was observed. The results of this study suggest that association of different controversial mutations of M. tuberculosis genes to the drug resistance phenotype should be done in respect to genetic lineages.
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Affiliation(s)
- Matiss Bauskenieks
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia
| | - Ilva Pole
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia; Center of Tuberculosis and Lung Diseases, Riga East University Hospital, Stopinu p., Riga, LV-2118, Latvia
| | - Girts Skenders
- Center of Tuberculosis and Lung Diseases, Riga East University Hospital, Stopinu p., Riga, LV-2118, Latvia
| | - Inta Jansone
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia
| | - Lonija Broka
- Center of Tuberculosis and Lung Diseases, Riga East University Hospital, Stopinu p., Riga, LV-2118, Latvia
| | - Anda Nodieva
- Rīga Stradiņš University, Dzirciema Street 16, Riga, LV-1007, Latvia
| | - Iveta Ozere
- Rīga Stradiņš University, Dzirciema Street 16, Riga, LV-1007, Latvia
| | - Adrija Kalvisa
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia
| | - Renate Ranka
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia; Rīga Stradiņš University, Dzirciema Street 16, Riga, LV-1007, Latvia.
| | - Viesturs Baumanis
- Latvian Biomedical Research and Study Centre, Ratsupites Street 1, Riga, LV-1067, Latvia
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Disparities in capreomycin resistance levels associated with the rrs A1401G mutation in clinical isolates of Mycobacterium tuberculosis. Antimicrob Agents Chemother 2014; 59:444-9. [PMID: 25385119 DOI: 10.1128/aac.04438-14] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
As the prevalence of multidrug-resistant and extensively drug-resistant tuberculosis strains continues to rise, so does the need to develop accurate and rapid molecular tests to complement time-consuming growth-based drug susceptibility testing. Performance of molecular methods relies on the association of specific mutations with phenotypic drug resistance and while considerable progress has been made for resistance detection of first-line antituberculosis drugs, rapid detection of resistance for second-line drugs lags behind. The rrs A1401G allele is considered a strong predictor of cross-resistance between the three second-line injectable drugs, capreomycin (CAP), kanamycin, and amikacin. However, discordance is often observed between the rrs A1401G mutation and CAP resistance, with up to 40% of rrs A1401G mutants being classified as CAP susceptible. We measured the MICs to CAP in 53 clinical isolates harboring the rrs A1401G mutation and found that the CAP MICs ranged from 8 μg/ml to 40 μg/ml. These results were drastically different from engineered A1401G mutants generated in isogenic Mycobacterium tuberculosis, which exclusively exhibited high-level CAP MICs of 40 μg/ml. These data support the results of prior studies, which suggest that the critical concentration of CAP (10 μg/ml) used to determine resistance by indirect agar proportion may be too high to detect all CAP-resistant strains and suggest that a larger percentage of resistant isolates could be identified by lowering the critical concentration. These data also suggest that differences in resistance levels among clinical isolates are possibly due to second site or compensatory mutations located elsewhere in the genome.
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Molecular detection and characterization of resistant genes in Mycobacterium tuberculosis complex from DNA isolated from tuberculosis patients in the Eastern Cape province South Africa. BMC Infect Dis 2014; 14:479. [PMID: 25186245 PMCID: PMC4161913 DOI: 10.1186/1471-2334-14-479] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 09/01/2014] [Indexed: 11/24/2022] Open
Abstract
Background Tuberculosis (TB) in both animals and humans is caused by Mycobacterium tuberculosis complex (MTBC) primarily transmitted by inhalation of aerosolized droplets containing the organism. Multi-drug resistance (MDR) and extensive drug resistance (XDR) are evolutionary features of Mycobacterium tuberculosis to subvert the antibiotic regimes in place. The heavy burden of TB worsened by HIV endemic in South Africa motivated for the investigation of MTBC prevalence among TB patients in Port Elizabeth and the amplification and sequencing of the DNA amplicons known to confer resistance to TB drugs. Methods Three thousand eight hundred and ten (3810) sputum specimens were processed and DNA was isolated from sputum specimens collected from different hospitals and health care places in the Eastern Cape Province, South Africa. DNA was amplified using the Seeplex® MTB Nested ACE detection assay. The agar-dilution proportion method was used to perform drug-sensitivity testing using 7H10 Middlebrook medium. Target genes known to confer resistance to first and second-line drugs were amplified and the amplicons sequenced. Results One hundred and ninety (5%) DNA samples tested positive for MTBC and from the resistant profiles of the 190 positive samples, we noted that multidrug-resistant TB was identified in 189 (99.5%) with 190 (100%) patients infected with MTB resistant to isoniazid and 189 (99.5%) having MTB resistant to rifampicin. Other percentages of drug resistance observed including 40% pre-XDR and 60% of XDR. Conclusion This study provides valuable data on the different kinds of mutations occurring at various target loci in resistant MTBC strains isolated from samples obtained from the Eastern Cape Province. The results obtained reveal a high incidence of MDR amongst the positive samples from Eastern Cape Province, South Africa. Electronic supplementary material The online version of this article (doi:10.1186/1471-2334-14-479) contains supplementary material, which is available to authorized users.
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Drug Resistance Mechanisms in Mycobacterium tuberculosis. Antibiotics (Basel) 2014; 3:317-40. [PMID: 27025748 PMCID: PMC4790366 DOI: 10.3390/antibiotics3030317] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/20/2014] [Accepted: 06/23/2014] [Indexed: 01/16/2023] Open
Abstract
Tuberculosis (TB) is a serious public health problem worldwide. Its situation is worsened by the presence of multidrug resistant (MDR) strains of Mycobacterium tuberculosis, the causative agent of the disease. In recent years, even more serious forms of drug resistance have been reported. A better knowledge of the mechanisms of drug resistance of M. tuberculosis and the relevant molecular mechanisms involved will improve the available techniques for rapid drug resistance detection and will help to explore new targets for drug activity and development. This review article discusses the mechanisms of action of anti-tuberculosis drugs and the molecular basis of drug resistance in M. tuberculosis.
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Sowajassatakul A, Prammananan T, Chaiprasert A, Phunpruch S. Molecular characterization of amikacin, kanamycin and capreomycin resistance in M/XDR-TB strains isolated in Thailand. BMC Microbiol 2014; 14:165. [PMID: 24953243 PMCID: PMC4076439 DOI: 10.1186/1471-2180-14-165] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 06/17/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) makes the treatment and control of tuberculosis difficult. Rapid detection of drug-resistant strains is important for the successful treatment of drug-resistant tuberculosis; however, not all resistance mechanisms to the injectable second-line drugs such as amikacin (AK), kanamycin (KM), and capreomycin (CAP) are well understood. This study aims to validate the mechanisms associated with AK, KM, and CAP resistance in M. tuberculosis clinical strains isolated in Thailand. RESULTS A total of 15,124 M. tuberculosis clinical strains were isolated from 23,693 smear-positive sputum samples sent from 288 hospitals in 46 of 77 provinces of Thailand. Phenotypic analysis identified 1,294 strains as MDR-TB and second-line drugs susceptibility was performed in all MDR-TB strains and revealed 58 XDR-TB strains. Twenty-nine KM-resistant strains (26 XDR-TB and 3 MDR-TB) could be retrieved and their genes associated with AK, KM, and CAP resistance were investigated compared with 27 KM-susceptible strains. Mutation of the rrs (A1401G) was found in 21 out of 29 KM-resistant strains whereas mutations of eis either at C-14 T or at G-37 T were found in 5 strains. Three remaining KM-resistant strains did not contain any known mutations. Capreomycin resistance was determined in 28 of 29 KM-resistant strains. Analysis of tlyA revealed that the A33G mutation was found in all CAP-resistant strains and also in susceptible strains. In contrast, the recently identified tlyA mutation T539G and the novel Ins49GC were found in two and one CAP-resistant strains, respectively. In addition, our finding demonstrated the insertion of cytosine at position 581 of the tap, a putative drug efflux encoding gene, in both KM-resistant and KM-susceptible strains. CONCLUSIONS Our finding demonstrated that the majority of KM resistance mechanism in Thai M. tuberculosis clinical strains was rrs mutation at A1401G. Mutations of the eis promoter region either at C-14 T or G-37 T was found in 5 of 29 strains whereas three strains did not contain any known mutations. For CAP resistance, 3 of 28 CAP-resistant strains contained either T539G or Ins49GC mutations at tlyA that might be associated with the resistant phenotype.
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Affiliation(s)
- Angkanang Sowajassatakul
- Department of Biology, Faculty of Science, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand
| | - Therdsak Prammananan
- Tuberculosis Research Laboratory, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Thailand Science Park, Pathumthani 12120, Thailand
- Drug Resistance Tuberculosis Research Fund, Siriraj Foundation, Bangkok 10700, Thailand
| | - Angkana Chaiprasert
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Drug Resistance Tuberculosis Research Fund, Siriraj Foundation, Bangkok 10700, Thailand
| | - Saranya Phunpruch
- Department of Biology, Faculty of Science, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand
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Molecular and phenotypic characterization of multidrug-resistant Mycobacterium tuberculosis isolates resistant to kanamycin, amikacin, and capreomycin in China. Eur J Clin Microbiol Infect Dis 2014; 33:1959-66. [DOI: 10.1007/s10096-014-2144-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 04/28/2014] [Indexed: 10/25/2022]
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Banerjee R, Schecter GF, Flood J, Porco TC. Extensively drug-resistant tuberculosis: new strains, new challenges. Expert Rev Anti Infect Ther 2014; 6:713-24. [DOI: 10.1586/14787210.6.5.713] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Silva C, Perdigao J, Alverca E, de Matos APA, Carvalho PA, Portugal I, Jordao L. Exploring the contribution of mycobacteria characteristics in their interaction with human macrophages. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2013; 19:1159-1169. [PMID: 23790221 DOI: 10.1017/s1431927613001906] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Tuberculosis (TB) is a major health problem. The emergence of multidrug resistant (MDR) Mycobacterium tuberculosis (Mtb) isolates confounds treatment strategies. In Portugal, cases of MDR-TB are reported annually with an increased incidence noted in Lisbon. The majority of these MDR-TB cases are due to closely related mycobacteria known collectively as the Lisboa family and Q1 cluster. Genetic determinants linked to drug resistance have been exhaustively studied resulting in the identification of family and cluster specific mutations. Nevertheless, little is known about other factors involved in development of mycobacteria drug resistance. Here, we complement genetic analysis with the study of morphological and structural features of the Lisboa family and Q1 cluster isolates by using scanning and transmission electron microscopy. This analysis allowed the identification of structural differences, such as cell envelope thickness, between Mtb clinical isolates that are correlated with antibiotic resistance. The infection of human monocyte derived macrophages allowed us to document the relative selective advantage of the Lisboa family isolates over other circulating Mtb isolates.
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Affiliation(s)
- Carla Silva
- Centro de Patogénese Molecular, URIA, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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Du Q, Dai G, Long Q, Yu X, Dong L, Huang H, Xie J. Mycobacterium tuberculosis rrs A1401G mutation correlates with high-level resistance to kanamycin, amikacin, and capreomycin in clinical isolates from mainland China. Diagn Microbiol Infect Dis 2013; 77:138-42. [DOI: 10.1016/j.diagmicrobio.2013.06.031] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 05/29/2013] [Accepted: 06/23/2013] [Indexed: 10/26/2022]
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29
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Mpagama SG, Heysell SK, Ndusilo ND, Kumburu HH, Lekule IA, Kisonga RM, Gratz J, Boeree MJ, Houpt ER, Kibiki GS. Diagnosis and interim treatment outcomes from the first cohort of multidrug-resistant tuberculosis patients in Tanzania. PLoS One 2013; 8:e62034. [PMID: 23675411 PMCID: PMC3652861 DOI: 10.1371/journal.pone.0062034] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 03/15/2013] [Indexed: 11/19/2022] Open
Abstract
Setting Kibong’oto National Tuberculosis Hospital (KNTH), Kilimanjaro, Tanzania. Objective Characterize the diagnostic process and interim treatment outcomes from patients treated for multidrug-resistant tuberculosis (MDR-TB) in Tanzania. Design A retrospective cohort study was performed among all patients treated at KNTH for pulmonary MDR-TB between November 2009 and September 2011. Results Sixty-one culture-positive MDR-TB patients initiated therapy, 60 (98%) with a prior history of TB treatment. Forty-one (67%) were male and 9 (14%) were HIV infected with a mean CD4 count of 424 (±106) cells/µl. The median time from specimen collection to MDR-TB diagnosis and from diagnosis to initiation of MDR-TB treatment was 138 days (IQR 101–159) and 131 days (IQR 32–233), respectively. Following treatment initiation four (7%) patients died (all HIV negative), 3 (5%) defaulted, and the remaining 54 (89%) completed the intensive phase. Most adverse drug reactions were mild to moderate and did not require discontinuation of treatment. Median time to culture conversion was 2 months (IQR 1–3) and did not vary by HIV status. In 28 isolates available for additional second-line drug susceptibility testing, fluoroquinolone, aminoglycoside and para-aminosalicylic acid resistance was rare yet ethionamide resistance was present in 9 (32%). Conclusion The majority of MDR-TB patients from this cohort had survived a prolonged referral process, had multiple episodes of prior TB treatment, but did not have advanced AIDS and converted to culture negative early while completing an intensive inpatient regimen without serious adverse event. Further study is required to determine the clinical impact of second-line drug susceptibility testing and the feasibility of alternatives to prolonged hospitalization.
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Zhang X, Zhao B, Huang H, Zhu Y, Peng J, Dai G, Jiang G, Liu L, Zhao Y, Jin Q. Co-occurrence of amikacin-resistant and -susceptible Mycobacterium tuberculosis isolates in clinical samples from Beijing, China. J Antimicrob Chemother 2013; 68:1537-42. [PMID: 23539239 DOI: 10.1093/jac/dkt082] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES This study examined the phenomenon of heteroresistance in Mycobacterium tuberculosis clinical isolates obtained from retreated patients in Beijing, China between 2006 and 2011. METHODS The iPLEX Gold assay platform was used to determine the prevalence of heteroresistance to injectable second-line drugs (amikacin, kanamycin and capreomycin) in resistant isolates. RESULTS Heteroresistance was identified in 10.9% of 220 phenotypic amikacin-resistant isolates. CONCLUSIONS Heteroresistance was related mainly to the short duration and repeated use of amikacin and capreomycin during retreatment. These findings further our understanding of the evolution of resistance to injectable drugs used for tuberculosis treatment and help guide the rational use of injectable drugs during therapy.
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Affiliation(s)
- Xiaobing Zhang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100176, China
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Rapid diagnosis of drug resistance to fluoroquinolones, amikacin, capreomycin, kanamycin and ethambutol using genotype MTBDRsl assay: a meta-analysis. PLoS One 2013; 8:e55292. [PMID: 23383320 PMCID: PMC3562191 DOI: 10.1371/journal.pone.0055292] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 12/20/2012] [Indexed: 11/19/2022] Open
Abstract
Background There are urgent needs for rapid and accurate drug susceptibility testing of M. tuberculosis. GenoType MTBDRsl is a new molecular kit designed for rapid identification of the resistance to the second-line antituberculosis drugs with a single strip. In recent years, it has been evaluated in many settings, but with varied results. The aim of this meta-analysis was to synthesize the latest data on the diagnostic accuracy of GenoType MTBDRsl in detecting drug resistance to fluoroquinolones, amikacin, capreomycin, kanamycin and ethambutol, in comparison with the phenotypic drug susceptibility test. Methods This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. The search terms of “MTBDRsl” and “tuberculosis” were used on PubMed, EMBASE, and Web of Science. QUADAS-2 was used to assess the quality of included studies. Data were analyzed by Meta-Disc 1.4. We calculated the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and corresponding 95% confidence interval (CI) for each study. From these calculations, forest plots and summary receiver operating characteristic (SROC) curves were produced. Results Patient selection bias as well as flow and timing bias were observed in most studies. The summarized sensitivity (95% CI) was 0.874(0.845–0.899), 0.826(0.777–0.869), 0.820(0.772–0.862), 0.444(0.396–0.492), and 0.679(0.652–0.706) for fluoroquinolones, amikacin, capreomycin, kanamycin, and ethambutol, respectively. The specificity (95% CI) was 0.971(0.961–0.980), 0.995(0.987–0.998), 0.973(0.963–0.981), 0.993(0.985–0.997), and 0.799(0.773–0.823), respectively. The AUC (standard error) were 0.9754(0.0203), 0.9300(0.0598), 0.9885(0.0038), 0.9689(0.0359), and 0.6846(0.0550), respectively. Conclusion Genotype MTBDRsl showed good accuracy for detecting drug resistance to fluoroquinolones, amikacin and capreomycin, but it may not be an appropriate choice for kanamycin and ethambutol. The lack of data did not allow for proper evaluation of the test on clinical specimens. Further systematic assessment of diagnostic performance should be carried out on direct clinical samples.
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Oh CT, Moon C, Choi TH, Kim BS, Jang J. Mycobacterium marinum infection in Drosophila melanogaster for antimycobacterial activity assessment. J Antimicrob Chemother 2012; 68:601-9. [PMID: 23118147 DOI: 10.1093/jac/dks425] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES The major advantages of Drosophila melanogaster are a well-characterized immune system and high degree of susceptibility to tuberculosis caused by Mycobacterium marinum. The D. melanogaster-M. marinum infection model is gaining momentum as a screening tool because it is genetically amenable, low priced, rapid, technically convenient and ethically acceptable. In this context, the aim of this study was to develop a new, effective D. melanogaster-M. marinum in vivo efficacy model for antimycobacterial drug discovery. METHODS D. melanogaster were challenged with intra-abdominal injections of M. marinum and infected flies were fed with a fly medium containing isoniazid, rifampicin, ethambutol, pyrazinamide, amikacin, dinitrobenzamide or ampicillin dissolved in DMSO at different concentrations (0, 100 and 500 mg/L). Bacterial dissemination in flies was monitored by fluorescence microscopy/cfu counts and a fly survival curve was plotted. RESULTS The D. melanogaster-M. marinum model allowed assessment of the effectiveness of antibiotic treatment not only with conventional drugs, but also with newly discovered antimycobacterial agents. Rifampicin, dinitrobenzamide, amikacin and isoniazid effectively extended the life span of infected flies and ethambutol showed slightly improved survival. However, M. marinum infection was not cured by ampicillin or pyrazinamide. CONCLUSIONS This D. melanogaster-M. marinum infection/curing methodology may be valuable in the rapid evaluation of the activity of new antimycobacterial agents in drug discovery.
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Affiliation(s)
- Chun-Taek Oh
- Institut Pasteur Korea, Seongnam-si, Gyeonggi-do, Korea
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Kumar D, Palaniyandi K, Challu VK, Kumar P, Narayanan S. PknE, a serine/threonine protein kinase from Mycobacterium tuberculosis has a role in adaptive responses. Arch Microbiol 2012; 195:75-80. [DOI: 10.1007/s00203-012-0848-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 09/25/2012] [Accepted: 10/08/2012] [Indexed: 10/27/2022]
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Engohang-Ndong J. Antimycobacterial drugs currently in Phase II clinical trials and preclinical phase for tuberculosis treatment. Expert Opin Investig Drugs 2012; 21:1789-800. [PMID: 22991970 DOI: 10.1517/13543784.2012.724397] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION In 2010, about 8.8 million new cases of tuberculosis were recorded and 1.1 million people died of tuberculosis worldwide. Although numbers are in decrease since 2006, tuberculosis still represents a global issue and a major public health threat, due to appearance of multidrug-resistant and extensively drug-resistant tuberculosis cases. Although anti-tuberculosis drugs currently used are effective against tuberculosis, they present however more and more limits, especially in treating complex cases of tuberculosis, increasing therefore the need to develop new tools and approaches to treat tuberculosis today. AREAS COVERED In this review, we describe anti-tuberculosis drugs in Phase II clinical trials and in preclinical phase that are likely to play a crucial role in the management of tuberculosis cases in a near future. SQ109, TMC207, nitroimidazoles, and oxazolidinones are currently in Phase II clinical trials while BDM31343, SQ641, CPZEN-45, RBx 8700, DC-159a, and BTZ043 are in preclinical phase. CONCLUSION These drugs, alone or in different combinations represent a promising future for the treatment of tuberculosis. Continual conjugative efforts between governments and private organizations worldwide are essential for building new strategies for discovery and the development of new anti-tuberculosis drugs.
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Affiliation(s)
- Jean Engohang-Ndong
- Kent State University at Tuscarawas, Department of Biological Sciences, 330 University Dr. NE; New Philadelphia, OH 44663, USA.
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Georghiou SB, Magana M, Garfein RS, Catanzaro DG, Catanzaro A, Rodwell TC. Evaluation of genetic mutations associated with Mycobacterium tuberculosis resistance to amikacin, kanamycin and capreomycin: a systematic review. PLoS One 2012; 7:e33275. [PMID: 22479378 PMCID: PMC3315572 DOI: 10.1371/journal.pone.0033275] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 02/12/2012] [Indexed: 11/23/2022] Open
Abstract
Background Rapid molecular diagnostics for detecting multidrug-resistant and extensively drug-resistant tuberculosis (M/XDR-TB) primarily identify mutations in Mycobacterium tuberculosis (Mtb) genes associated with drug resistance. Their accuracy, however, is dependent largely on the strength of the association between a specific mutation and the phenotypic resistance of the isolate with that mutation, which is not always 100%. While this relationship is well established and reliable for first-line anti-TB drugs, rifampin and isoniazid, it is less well-studied and understood for second-line, injectable drugs, amikacin (AMK), kanamycin (KAN) and capreomycin (CAP). Methodology/Principal Findings We conducted a systematic review of all published studies evaluating Mtb mutations associated with resistance to AMK, KAN, CAP in order to characterize the diversity and frequency of mutations as well as describe the strength of the association between specific mutations and phenotypic resistance in global populations. Our objective was to determine the potential utility and reliability of these mutations as diagnostic markers for detecting AMK, KAN and CAP resistance. Mutation data was reviewed for 1,585 unique clinical isolates from four continents and over 18 countries. Mutations in the rrs, tlyA, eis promoter and gidB genes were associated with AMK, KAN and/or CAP resistance. Conclusions/Significance The rrs A1401G mutation was present in the majority of AMK, KAN and CAP resistant Mtb strains reviewed, but was also found in 7% of CAP susceptible strains. The 1401 mutation alone, however, was not found with sufficient frequency to detect more than 70–80% of global Mtb strains resistant to AMK and CAP, and 60% of strains resistant to KAN. Additional mutations in the rrs, eis promoter, tlyA and gidB genes appear to be associated with resistance and could improve sensitivity and specificity of future diagnostics.
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Affiliation(s)
- Sophia B. Georghiou
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Marisa Magana
- University of California San Diego Medical Center, San Diego, California, United States of America
| | - Richard S. Garfein
- Division of Global Public Health, University of California San Diego School of Medicine, La Jolla, California, United States of America
| | - Donald G. Catanzaro
- Department of Family and Preventive Medicine, University of California San Diego Health Services Research Center, La Jolla, California, United States of America
| | - Antonino Catanzaro
- University of California San Diego Medical Center, San Diego, California, United States of America
| | - Timothy C. Rodwell
- Division of Global Public Health, University of California San Diego School of Medicine, La Jolla, California, United States of America
- * E-mail:
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Detection of resistance to second-line antituberculosis drugs by use of the genotype MTBDRsl assay: a multicenter evaluation and feasibility study. J Clin Microbiol 2012; 50:1593-7. [PMID: 22378910 DOI: 10.1128/jcm.00039-12] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rate of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) has been steadily increasing in countries of the former USSR. The availability of rapid and reliable methods for the detection of drug resistance to second-line drugs is vital for adequate patient management. We evaluated the performance of the Genotype MTBDRsl assay compared to that of phenotypic drug susceptibility testing (Becton Dickinson Bactec MGIT 960 system) with a test panel of 200 Mycobacterium tuberculosis isolates at four sites in Eastern Europe. The interpretability of the Genotype MTBDRsl assay was over 95%. The sensitivity for the detection of resistance to fluoroquinolones, ethambutol, amikacin, and capreomycin varied between 77.3% and 92.3%; however, it was much lower for kanamycin (42.7%). The sensitivity for the detection of XDR TB was 22.6%. The test specificity was over 82% for all drugs. The assay presents a good screening tool for the rapid detection of resistance to individual second-line drugs and can be recommended for use in countries with a high burden of MDR/XDR TB. The sensitivity for the detection of kanamycin resistance needs improvement.
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Park C, Sung N, Hwang S, Jeon J, Won Y, Min J, Kim CT, Kang H. Evaluation of Reverse Hybridization Assay for Detecting Fluoroquinolone and Kanamycin Resistance in Multidrug-ResistanceMycobacterium tuberculosisClinical Isolates. Tuberc Respir Dis (Seoul) 2012. [DOI: 10.4046/trd.2012.72.1.44] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kondo J. A Structural Basis for the Antibiotic Resistance Conferred by an A1408G Mutation in 16S rRNA and for the Antiprotozoal Activity of Aminoglycosides. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201106084] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Kondo J. A Structural Basis for the Antibiotic Resistance Conferred by an A1408G Mutation in 16S rRNA and for the Antiprotozoal Activity of Aminoglycosides. Angew Chem Int Ed Engl 2011; 51:465-8. [DOI: 10.1002/anie.201106084] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Indexed: 01/05/2023]
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Böttger EC. The ins and outs of Mycobacterium tuberculosis drug susceptibility testing. Clin Microbiol Infect 2011; 17:1128-34. [PMID: 21631641 DOI: 10.1111/j.1469-0691.2011.03551.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Drug susceptibility testing of Mycobacterium tuberculosis in the diagnostic laboratory classifies clinical isolates as either drug-'resistant' or drug-'susceptible', on the basis of their ability to grow in the presence of a 'critical concentration' of the test compound. From knowledge of the mechanisms that underlie drug resistance, it has become evident that drug resistance in M. tuberculosis is quite heterogeneous and involves low-level, moderate-level and high-level drug resistance phenotypes. Different mutations are associated with different levels of phenotypic resistance, and the acquisition of a genetic alteration leading to a decrease in drug susceptibility does not inevitably exclude the affected compound from treatment regimens. As a result, the simple categorization of clinical M. tuberculosis isolates as 'resistant' on the basis of susceptibility testing at 'critical concentrations' may need to be revised and supplemented by quantitative measures of resistance testing to reflect the biological complexity of drug resistance, with the view of optimally exploiting the compounds available for treatment.
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Affiliation(s)
- E C Böttger
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland.
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41
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Almeida Da Silva PEA, Palomino JC. Molecular basis and mechanisms of drug resistance in Mycobacterium tuberculosis: classical and new drugs. J Antimicrob Chemother 2011; 66:1417-30. [PMID: 21558086 DOI: 10.1093/jac/dkr173] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Tuberculosis (TB) remains one of the leading public health problems worldwide. Declared as a global emergency in 1993 by the WHO, its control is hampered by the emergence of multidrug resistance (MDR), defined as resistance to at least rifampicin and isoniazid, two key drugs in the treatment of the disease. More recently, severe forms of drug resistance such as extensively drug-resistant (XDR) TB have been described. After the discovery of several drugs with anti-TB activity, multidrug therapy became fundamental for control of the disease. Major advances in molecular biology and the availability of new information generated after sequencing the genome of Mycobacterium tuberculosis increased our knowledge of the mechanisms of resistance to the main anti-TB drugs. Better knowledge of the mechanisms of drug resistance in TB and the molecular mechanisms involved will help us to improve current techniques for rapid detection and will also stimulate the exploration of new targets for drug activity and drug development. This article presents an updated review of the mechanisms and molecular basis of drug resistance in M. tuberculosis. It also comments on the several gaps in our current knowledge of the molecular mechanisms of drug resistance to the main classical and new anti-TB drugs and briefly discusses some implications of the development of drug resistance and fitness, transmission and pathogenicity of M. tuberculosis.
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Engstrom A, Perskvist N, Werngren J, Hoffner SE, Jureen P. Comparison of clinical isolates and in vitro selected mutants reveals that tlyA is not a sensitive genetic marker for capreomycin resistance in Mycobacterium tuberculosis. J Antimicrob Chemother 2011; 66:1247-54. [DOI: 10.1093/jac/dkr109] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Blaschitz M, Hasanacevic D, Hufnagl P, Hasenberger P, Pecavar V, Meidlinger L, Konrad M, Allerberger F, Indra A. Real-time PCR for single-nucleotide polymorphism detection in the 16S rRNA gene as an indicator for extensive drug resistance in Mycobacterium tuberculosis. J Antimicrob Chemother 2011; 66:1243-6. [DOI: 10.1093/jac/dkr070] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Caminero JA, Sotgiu G, Zumla A, Migliori GB. Best drug treatment for multidrug-resistant and extensively drug-resistant tuberculosis. THE LANCET. INFECTIOUS DISEASES 2010; 10:621-9. [PMID: 20797644 DOI: 10.1016/s1473-3099(10)70139-0] [Citation(s) in RCA: 328] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis are generally thought to have high mortality rates. However, many cases can be treated with the right combination and rational use of available antituberculosis drugs. This Review describes the evidence available for each drug and discusses the basis for recommendations for the treatment of patients with MDR and XDR tuberculosis. The recommended regimen is the combination of at least four drugs to which the Mycobacterium tuberculosis isolate is likely to be susceptible. Drugs are chosen with a stepwise selection process through five groups on the basis of efficacy, safety, and cost. Among the first group (the oral first-line drugs) high-dose isoniazid, pyrazinamide, and ethambutol are thought of as an adjunct for the treatment of MDR and XDR tuberculosis. The second group is the fluoroquinolones, of which the first choice is high-dose levofloxacin. The third group are the injectable drugs, which should be used in the following order: capreomycin, kanamycin, then amikacin. The fourth group are called the second-line drugs and should be used in the following order: thioamides, cycloserine, then aminosalicylic acid. The fifth group includes drugs that are not very effective or for which there are sparse clinical data. Drugs in group five should be used in the following order: clofazimine, amoxicillin with clavulanate, linezolid, carbapenems, thioacetazone, then clarithromycin.
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Affiliation(s)
- José A Caminero
- Servicio de Neumología, Hospital General de Gran Canaria, Las Palmas, Canary Islands, Spain.
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Shcherbakov D, Akbergenov R, Matt T, Sander P, Andersson DI, Böttger EC. Directed mutagenesis of Mycobacterium smegmatis 16S rRNA to reconstruct the in vivo evolution of aminoglycoside resistance in Mycobacterium tuberculosis. Mol Microbiol 2010; 77:830-40. [DOI: 10.1111/j.1365-2958.2010.07218.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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46
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Detection by GenoType MTBDRsl test of complex mechanisms of resistance to second-line drugs and ethambutol in multidrug-resistant Mycobacterium tuberculosis complex isolates. J Clin Microbiol 2010; 48:1683-9. [PMID: 20335420 DOI: 10.1128/jcm.01947-09] [Citation(s) in RCA: 146] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The GenoType MTBDRsl test rapidly detects resistance to ethambutol, fluoroquinolones, and second-line aminoglycosides (amikacin and kanamycin) and cyclic peptide (capreomycin) in Mycobacterium tuberculosis. A set of 41 multidrug-resistant (MDR) M. tuberculosis strains, 8 extensively drug-resistant (XDR) M. tuberculosis strains, and 3 non-MDR M. tuberculosis strains were tested by the MTBDRsl test and by DNA sequencing of the resistance-determining regions in gyrA and gyrB (fluoroquinolones [FQ]), rpsL (streptomycin), rrs and tlyA (aminoglycosides and/or cyclic peptide), and embB (ethambutol). The sensitivity and specificity of the MTBDRsl test were as follows: 87% and 96%, respectively, for fluoroquinolones; 100% for both for amikacin; 77% and 100%, respectively, for kanamycin, 80% and 98%, respectively, for capreomycin; and 57% and 92%, respectively, for ethambutol. Analysis of the discrepant results indicated that three FQ-resistant strains (including one XDR strain) with mutations in gyrB were missed by the MTBDRsl test and that one FQ-susceptible strain, identified as resistant by the MTBDRsl test, had a double mutation (T80A-A90G) in GyrA that did not confer resistance to FQ. Five strains (including two XDR strains) without mutations in rrs were monoresistant to aminoglycosides or cyclic peptide and were missed by the MTBDRsl test. Finally, 12/28 ethambutol-resistant strains had no mutation at codon 306 in embB, while 2/24 ethambutol-susceptible strains had such a mutation. In conclusion, the MTBDRsl test efficiently detects the most common mutations involved in resistance to fluoroquinolones, aminoglycosides/cyclic peptide, and ethambutol and accurately assesses susceptibility to amikacin. However, due to mutations not included in the test (particularly in gyrB) or resistance mechanisms not yet characterized (particularly those related to ethambutol resistance and to monoresistance to aminoglycosides or cyclic peptide), the wild-type results yielded by the MTBDRsl test should be confirmed by drug susceptibility testing.
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Wild-type MIC distributions for aminoglycoside and cyclic polypeptide antibiotics used for treatment of Mycobacterium tuberculosis infections. J Clin Microbiol 2010; 48:1853-8. [PMID: 20237102 DOI: 10.1128/jcm.00240-10] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aminoglycosides and cyclic polypeptides are essential drugs in the treatment of multidrug-resistant tuberculosis, underscoring the need for accurate and reproducible drug susceptibility testing (DST). The epidemiological cutoff value (ECOFF) separating wild-type susceptible strains from non-wild-type strains is an important but rarely used tool for indicating susceptibility breakpoints against Mycobacterium tuberculosis. In this study, we established wild-type MIC distributions on Middlebrook 7H10 medium for amikacin, kanamycin, streptomycin, capreomycin, and viomycin using 90 consecutive clinical isolates and 21 resistant strains. Overall, the MIC variation between and within runs did not exceed +/-1 MIC dilution step, and validation of MIC values in Bactec 960 MGIT demonstrated good agreement. Tentative ECOFFs defining the wild type were established for all investigated drugs, including amikacin and viomycin, which currently lack susceptibility breakpoints for 7H10. Five out of seven amikacin- and kanamycin-resistant isolates were classified as susceptible to capreomycin according to the current critical concentration (10 mg/liter) but were non-wild type according to the ECOFF (4 mg/liter), suggesting that the critical concentration may be too high. All amikacin- and kanamycin-resistant isolates were clearly below the ECOFF for viomycin, and two of them were below the ECOFF for streptomycin, indicating that these two drugs may be considered for treatment of amikacin-resistant strains. Pharmacodynamic indices (peak serum concentration [Cmax]/MIC) were more favorable for amikacin and viomycin compared to kanamycin and capreomycin. In conclusion, our data emphasize the importance of establishing wild-type MIC distributions for improving the quality of drug susceptibility testing against Mycobacterium tuberculosis.
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Caminero JA. Tratamiento de la tuberculosis según el diferente patrón de resistencias. Med Clin (Barc) 2010; 134:173-81. [DOI: 10.1016/j.medcli.2008.12.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 12/18/2008] [Indexed: 10/20/2022]
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Overexpression of the chromosomally encoded aminoglycoside acetyltransferase eis confers kanamycin resistance in Mycobacterium tuberculosis. Proc Natl Acad Sci U S A 2009; 106:20004-9. [PMID: 19906990 DOI: 10.1073/pnas.0907925106] [Citation(s) in RCA: 232] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The emergence of multidrug-resistant (MDR) tuberculosis (TB) highlights the urgent need to understand the mechanisms of resistance to the drugs used to treat this disease. The aminoglycosides kanamycin and amikacin are important bactericidal drugs used to treat MDR TB, and resistance to one or both of these drugs is a defining characteristic of extensively drug-resistant TB. We identified mutations in the -10 and -35 promoter region of the eis gene, which encodes a previously uncharacterized aminoglycoside acetyltransferase. These mutations led to a 20-180-fold increase in the amount of eis leaderless mRNA transcript, with a corresponding increase in protein expression. Importantly, these promoter mutations conferred resistance to kanamycin [5 microg/mL < minimum inhibitory concentration (MIC) <or=40 microg/mL] but not to amikacin (MIC <4 microg/mL). Additionally, 80% of clinical isolates examined in this study that exhibited low-level kanamycin resistance harbored eis promoter mutations. These results have important clinical implications in that clinical isolates determined to be resistant to kanamycin may not be cross-resistant to amikacin, as is often assumed. Molecular detection of eis mutations should distinguish strains resistant to kanamycin and those resistant to kanamycin and amikacin. This may help avoid excluding a potentially effective drug from a treatment regimen for drug-resistant TB.
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High level of cross-resistance between kanamycin, amikacin, and capreomycin among Mycobacterium tuberculosis isolates from Georgia and a close relation with mutations in the rrs gene. Antimicrob Agents Chemother 2009; 53:5064-8. [PMID: 19752274 DOI: 10.1128/aac.00851-09] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aminoglycosides kanamycin and amikacin and the macrocyclic peptide capreomycin are key drugs for the treatment of multidrug-resistant tuberculosis (MDR-TB). The increasing rates of resistance to these drugs and the possible cross-resistance between them are concerns for MDR-TB therapy. Mutations in the 16S rRNA gene (rrs) have been associated with resistance to each of the drugs, and mutations of the tlyA gene, which encodes a putative rRNA methyltransferase, are thought to confer capreomycin resistance in Mycobacterium tuberculosis bacteria. Studies of possible cross-resistance have shown variable results. In this study, the MICs of these drugs for 145 clinical isolates from Georgia and the sequences of the rrs and tlyA genes of the isolates were determined. Of 78 kanamycin-resistant strains, 9 (11.5%) were susceptible to amikacin and 16 (20.5%) were susceptible to capreomycin. Four strains were resistant to capreomycin but were susceptible to the other drugs, whereas all amikacin-resistant isolates were resistant to kanamycin. Sequencing revealed six types of mutations in the rrs gene (A514C, C517T, A1401G, C1402T, C1443G, T1521C) but no mutations in the tlyA gene. The A514C, C517T, C1443G, and T1521C mutations showed no association with resistance to any of the drugs. The A1401G and C1402T mutations were observed in 65 kanamycin-resistant isolates and the 4 capreomycin-resistant isolates, respectively, whereas none of the susceptible isolates showed either of those mutations. The four mutants with the C1402T mutations showed high levels of resistance to capreomycin but no resistance to kanamycin and amikacin. Detection of the A1401G mutation appeared to be 100% specific for the detection of resistance to kanamycin and amikacin, while the sensitivities reached 85.9% and 94.2%, respectively.
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