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Mousavi-Sagharchi SMA, Afrazeh E, Seyyedian-Nikjeh SF, Meskini M, Doroud D, Siadat SD. New insight in molecular detection of Mycobacterium tuberculosis. AMB Express 2024; 14:74. [PMID: 38907086 PMCID: PMC11192714 DOI: 10.1186/s13568-024-01730-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 06/06/2024] [Indexed: 06/23/2024] Open
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis, is a pathogenic bacterium that has claimed millions of lives since the Middle Ages. According to the World Health Organization's report, tuberculosis ranks among the ten deadliest diseases worldwide. The presence of an extensive array of genes and diverse proteins within the cellular structure of this bacterium has provided us with a potent tool for diagnosis. While the culture method remains the gold standard for tuberculosis diagnosis, it is possible that molecular diagnostic methods, emphasis on the identification of mutation genes (e.g., rpoB and gyrA) and single nucleotide polymorphisms, could offer a safe and reliable alternative. Over the past few decades, as our understanding of molecular genetics has expanded, methods have been developed based on gene expansion and detection. These methods typically commence with DNA amplification through nucleic acid targeted techniques such as polymerase chain reaction. Various molecular compounds and diverse approaches have been employed in molecular assays. In this review, we endeavor to provide an overview of molecular assays for the diagnosis of tuberculosis with their properties (utilization, challenges, and functions). The ultimate goal is to explore the potential of replacing traditional bacterial methods with these advanced molecular diagnostic techniques.
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Affiliation(s)
| | - Elina Afrazeh
- Department of Marine Biology, Faculty of Marine Science, Khorramshahr University of Marine Science and Technology, Khorramshahr, Iran
| | | | - Maryam Meskini
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.
- Microbiology Research Center (MRC), Pasteur Institute of Iran, Tehran, Iran.
- Department of Genetics, Faculty of Natural and Agricultural Sciences, University of the Free State, Bloemfontein, 9301, South Africa.
- Student Research Committee, Pasteur Institute of Iran, Tehran, Iran.
| | - Delaram Doroud
- Department of Immunotherapy and Leishmania Vaccine Research, Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Davar Siadat
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.
- Microbiology Research Center (MRC), Pasteur Institute of Iran, Tehran, Iran.
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Otchere ID, Asante-Poku A, Akpadja KF, Diallo AB, Sanou A, Asare P, Osei-Wusu S, Onyejepu N, Diarra B, Dagnra YA, Kehinde A, Antonio M, Yeboah-Manu D. Opinion review of drug resistant tuberculosis in West Africa: tackling the challenges for effective control. Front Public Health 2024; 12:1374703. [PMID: 38827613 PMCID: PMC11141065 DOI: 10.3389/fpubh.2024.1374703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/29/2024] [Indexed: 06/04/2024] Open
Abstract
Drug-resistant (DR) tuberculosis (TB) is a major public health concern globally, complicating TB control and management efforts. West Africa has historically faced difficulty in combating DR-TB due to limited diagnostic skills, insufficient access to excellent healthcare, and ineffective healthcare systems. This has aided in the emergence and dissemination of DR Mycobacterium tuberculosis complex (MTBC) strains in the region. In the past, DR-TB patients faced insufficient resources, fragmented efforts, and suboptimal treatment outcomes. However, current efforts to combat DR-TB in the region are promising. These efforts include strengthening diagnostic capacities, improving access to quality healthcare services, and implementing evidence-based treatment regimens for DR-TB. Additionally, many West African National TB control programs are collaborating with international partners to scale up laboratory infrastructure, enhance surveillance systems, and promote infection control measures. Moreso, novel TB drugs and regimens, such as bedaquiline and delamanid, are being introduced to improve treatment outcomes for DR-TB cases. Despite these obstacles, there is optimism for the future of DR-TB control in West Africa. Investments are being made to improve healthcare systems, expand laboratory capacity, and support TB research and innovation. West African institutions are now supporting knowledge sharing, capacity building, and resource mobilization through collaborative initiatives such as the West African Network for TB, AIDS, and Malaria (WANETAM), the West African Health Organization (WAHO), and other regional or global partners. These efforts hold promise for improved diagnostics, optimized treatment regimens, and provide better patient outcomes in the future where drug-resistant TB in WA can be effectively controlled, reducing the burden of the disease, and improving the health outcomes of affected individuals.
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Affiliation(s)
- Isaac Darko Otchere
- Bacteriology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, Gambia
| | - Adwoa Asante-Poku
- Bacteriology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | | | - Awa Ba Diallo
- Biological Sciences Department, Faculty of Pharmacy at Cheikh Anta Diop University, Dakar, Senegal
| | - Adama Sanou
- Centre Muraz, Institut National de Santé Publique, Bobo-Dioulasso, Burkina Faso
| | - Prince Asare
- Bacteriology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Stephen Osei-Wusu
- Bacteriology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Nneka Onyejepu
- Microbiology Department, Center for Tuberculosis Research Laboratory, Nigerian Institute of Medical Research, Lagos, Nigeria
| | - Bassirou Diarra
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Aderemi Kehinde
- Department of Medical Microbiology and Parasitology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Martin Antonio
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, Gambia
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Centre for Epidemic Preparedness and Response, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Dorothy Yeboah-Manu
- Bacteriology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
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Georghiou SB, de Vos M, Velen K, Miotto P, Colman RE, Cirillo DM, Ismail N, Rodwell TC, Suresh A, Ruhwald M. Designing molecular diagnostics for current tuberculosis drug regimens. Emerg Microbes Infect 2023; 12:2178243. [PMID: 36752055 PMCID: PMC9980415 DOI: 10.1080/22221751.2023.2178243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Diagnostic development must occur in parallel with drug development to ensure the longevity of new treatment compounds. Despite an increasing number of novel and repurposed anti-tuberculosis compounds and regimens, there remains a large number of drugs for which no rapid and accurate molecular diagnostic option exists. The lack of rapid drug susceptibility testing for linezolid, bedaquiline, clofazimine, the nitroimidazoles (i.e pretomanid and delamanid) and pyrazinamide at any level of the healthcare system compromises the effectiveness of current tuberculosis and drug-resistant tuberculosis treatment regimens. In the context of current WHO tuberculosis treatment guidelines as well as promising new regimens, we identify the key diagnostic gaps for initial and follow-on tests to diagnose emerging drug resistance and aid in regimen selection. Additionally, we comment on potential gene targets for inclusion in rapid molecular drug susceptibility assays and sequencing assays for novel and repurposed drug compounds currently prioritized in current regimens, and evaluate the feasibility of mutation detection given the design of existing technologies. Based on current knowledge, we also propose design priorities for next generation molecular assays to support triage of tuberculosis patients to appropriate and effective treatment regimens. We encourage assay developers to prioritize development of these key molecular assays and support the continued evolution, uptake, and utility of sequencing to build knowledge of tuberculosis resistance mechanisms and further inform rapid treatment decisions in order to curb resistance to critical drugs in current regimens and achieve End TB targets.Trial registration: ClinicalTrials.gov identifier: NCT05117788..
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Affiliation(s)
| | | | | | - Paolo Miotto
- IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Rebecca E. Colman
- FIND, the Global Alliance for Diagnostics, Geneva, Switzerland,Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | | | | | - Timothy C. Rodwell
- FIND, the Global Alliance for Diagnostics, Geneva, Switzerland,Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Anita Suresh
- FIND, the Global Alliance for Diagnostics, Geneva, Switzerland
| | - Morten Ruhwald
- FIND, the Global Alliance for Diagnostics, Geneva, Switzerland, Morten Ruhwald FIND, the Global Alliance for Diagnostics, Campus Biotech, 9 Chemin des Mines, Geneva1202, Switzerland
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David A, Scott LE, Da Silva P, Mayne E, Stevens WS. Storage of Mycobacterium tuberculosis culture isolates in Microbank TM beads at a South African laboratory. Afr J Lab Med 2023; 12:2172. [PMID: 38023785 PMCID: PMC10646387 DOI: 10.4102/ajlm.v12i1.2172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 08/23/2023] [Indexed: 12/01/2023] Open
Abstract
Background Mycobacterium tuberculosis complex (MTBC) isolates are typically stored at -70 °C in cryovials containing 1 mL aliquots of a liquid medium, with or without 50% glycerol. Multiple uses of the culture stock may decrease the strain viability while increasing the risk of culture contamination. Small culture aliquots may be more practical; however, storage capacity remains challenging. MicrobankTM beads (25 beads/vial) for the long-term storage of fungal cultures is well documented, but their use for storing MTBC isolates is uninvestigated. Objective The study aimed to determine the feasibility of using MicrobankTM beads for long-term storage of MTBC isolates at a laboratory in South Africa. Methods In February 2020, 20 isolates in liquid culture were stored in MicrobankTM beads, following an in-house developed protocol, at -70 °C. At defined time points (16 months [15 June 2021] and 21 months [18 November 2021]), two beads were retrieved from each storage vial and assessed for viability and level of contamination. Results Stored liquid isolates demonstrated MTBC growth within an average time-to-detection of 18 days following retrieval, even at 21 months post storage. Contaminating organisms were detected in 2 of 80 (2.5%) culture isolates. Conclusion MicrobankTM beads will allow for the reculture of up to 25 culture isolates using a reduced culture volume compared to current storage methods. MicrobankTM beads represent a storage solution for the medium-term storage of MTBC isolates. What this study adds This study evaluated the use of MicrobankTM beads as an alternate method for storing MTBC culture isolates at -70 °C and provided a suitable option for medium-term storage of MTBC.
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Affiliation(s)
- Anura David
- Wits Diagnostic Innovation Hub, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Lesley E. Scott
- Wits Diagnostic Innovation Hub, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Pedro Da Silva
- National Priority Program, National Health Laboratory Services, Johannesburg, South Africa
| | - Elizabeth Mayne
- National Priority Program, National Health Laboratory Services, Johannesburg, South Africa
- Division of Immunology, University of Cape Town, Cape Town, South Africa
| | - Wendy S. Stevens
- Wits Diagnostic Innovation Hub, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- National Priority Program, National Health Laboratory Services, Johannesburg, South Africa
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Chen S, Liu H, Li T, Lai W, Liu L, Xu Y, Qu J. Using Microfluidic Chip and Allele-Specific PCR to Rapidly Identify Drug Resistance-Associated Mutations of Mycobacterium tuberculosis. Infect Drug Resist 2023; 16:4311-4323. [PMID: 37424666 PMCID: PMC10327919 DOI: 10.2147/idr.s410779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 06/20/2023] [Indexed: 07/11/2023] Open
Abstract
Background The currently used conventional susceptibility testing for drug-resistant Mycobacterium tuberculosis (M.TB) is limited due to being time-consuming and having low efficiency. Herein, we propose the use of a microfluidic-based method to rapidly detect drug-resistant gene mutations using Kompetitive Allele-Specific PCR (KASP). Methods A total of 300 clinical samples were collected, and DNA extraction was performed using the "isoChip®" Mycobacterium detection kit. Phenotypic susceptibility testing and Sanger sequencing were performed to sequence the PCR products. Allele-specific primers targeting 37 gene mutation sites were designed, and a microfluidic chip (KASP) was constructed using 112 reaction chambers to simultaneously detect multiple mutations. Chip validation was performed using clinical samples. Results Phenotypic susceptibility of clinical isolates revealed 38 rifampicin (RIF)-resistant, 64 isoniazid (INH)-resistant, 48 streptomycin (SM)-resistant and 23 ethambutol (EMB)-resistant strains, as well as 33 multi-drug-resistant TB (MDR-TB) strains and 20 strains fully resistant to all four drugs. Optimization of the chip-based detection system for drug resistance detection showed satisfactory specificity and maximum fluorescence at a DNA concentration of 1×101 copies/µL. Further analysis revealed that 76.32% of the RIF-resistant strains harbored rpoB gene mutations (sensitivity, 76.32%; specificity 100%), 60.93% of the INH-resistant strains had katG gene mutations (sensitivity, 60.93%; specificity, 100%), 66.66% of the SM-resistant strains carried drug resistance gene mutations (sensitivity, 66.66%; specificity, 99.2%), and 69.56% of the EMB-resistant strains had embB gene mutations (sensitivity, 69.56%; specificity, 100%). Further, the overall agreement between the microfluidic chip and Sanger sequencing was satisfactory, with a turnaround time of the microfluidic chip was approximately 2 hours, much shorter than the conventional DST method. Conclusion The proposed microfluidic-based KASP assay provides a cost-effective and convenient method for detecting mutations associated with drug resistance in M. tuberculosis. It represents a promising alternative to the traditional DST method, with satisfactory sensitivity and specificity and a much shorter turnaround time.
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Affiliation(s)
- Shan Chen
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
| | - Houming Liu
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
| | - Tianpin Li
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
| | - Wenjie Lai
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
| | - Lei Liu
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
| | - Youchun Xu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, People’s Republic of China
| | - Jiuxin Qu
- Department of Clinical Laboratory, Shenzhen Third People’s Hospital, National Clinical Research Center for Infectious Diseases, The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong Province, 518112, People’s Republic of China
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Management of Polydrug-Resistant Tuberculosis. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:medicina59020246. [PMID: 36837448 PMCID: PMC9967441 DOI: 10.3390/medicina59020246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 02/03/2023]
Abstract
Background and Objectives: There is a lack of information regarding the effective duration of treatment necessary to prevent the development of acquired resistance when fluoroquinolones (FQ), and/or pyrazinamide (Z) resistance has occurred in patients with polydrug-resistant tuberculosis and isoniazid resistance. The management of these kinds of patients should be carried out in experienced centers according to drug susceptibility test results, clinical status of the patient and the extensity of the disease. Materials and Methods: We evaluated treatment regimens, treatment outcomes, and drug adverse effects in seven patients with polydrug-resistant tuberculosis, including those with Z and/or FQ resistance in a retrospective analysis Results: Regarding the patients with polydrug-resistant tuberculosis in addition to isoniazid (H) resistance, three had Z, two had FQ, and the remaining two had both Z and FQ resistance. In the intensive phase of the treatment, the patients were given at least four drugs according to drug susceptibility tests, and at least three drugs in the continuation phase. The duration of treatment was 9-12 months. Two of the patients were foreign nationals, and could not be followed up with due to returning to their home countries. Regarding the remaining five patients, three of them were terminated as they completed treatment, and two as cured. No recurrence was observed in the first year of the treatment. The most common, and serious drug side effect was seen for amikacin. Conclusions: In patients with polydrug-resistant TB, if Z and/or FQ resistance is detected in addition to H resistance, the treatment of these patients should be conducted on a case-by-case basis, taking into account the patient's resistance pattern, clinical condition, and disease prognosis. Close monitoring of the side effects will increase the success rate of the treatment.
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Sawatpanich A, Petchsong S, Tumwasorn S, Rotcheewaphan S. Diagnostic performance of the Anyplex MTB/NTM real-time PCR in detection of Mycobacterium tuberculosis complex and nontuberculous mycobacteria from pulmonary and extrapulmonary specimens. Heliyon 2022; 8:e11935. [DOI: 10.1016/j.heliyon.2022.e11935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/02/2022] [Accepted: 11/18/2022] [Indexed: 11/27/2022] Open
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8
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AYDIN E, TARHAN G, ŞAHİN F, EREN S. Molecular epidemiological typing of M. tuberculosis isolates isolated from Turkey's Eastern Anatolia with in house PCR method. CUKUROVA MEDICAL JOURNAL 2022. [DOI: 10.17826/cumj.997873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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9
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Aono A, Murase Y, Minegishi M, Ohtawa S, Yano M, Chikamatsu K, Shimomura Y, Hosoya M, Igarashi Y, Morishige Y, Yamada H, Takaki A, Togashi K, Hiura M, Mitarai S. Clinical evaluation of the cobas® MTB-RIF/INH reagent and the cobas® 6800 for the detection of isoniazid and rifampicin resistance. Tuberculosis (Edinb) 2022; 134:102199. [DOI: 10.1016/j.tube.2022.102199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 03/09/2022] [Accepted: 03/15/2022] [Indexed: 11/24/2022]
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Bonnet I, Enouf V, Morel F, Ok V, Jaffré J, Jarlier V, Aubry A, Robert J, Sougakoff W. A Comprehensive Evaluation of GeneLEAD VIII DNA Platform Combined to Deeplex Myc-TB ® Assay to Detect in 8 Days Drug Resistance to 13 Antituberculous Drugs and Transmission of Mycobacterium tuberculosis Complex Directly From Clinical Samples. Front Cell Infect Microbiol 2021; 11:707244. [PMID: 34778100 PMCID: PMC8586210 DOI: 10.3389/fcimb.2021.707244] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 10/04/2021] [Indexed: 11/21/2022] Open
Abstract
The GeneLEAD VIII (Diagenode, Belgium) is a new, fully automated, sample-to-result precision instrument for the extraction of DNA and PCR detection of Mycobacterium tuberculosis complex (MTBC) directly from clinical samples. The Deeplex Myc-TB® assay (Genoscreen, France) is a diagnostic kit based on the deep sequencing of a 24-plexed amplicon mix allowing simultaneously the detection of resistance to 13 antituberculous (antiTB) drugs and the determination of spoligotype. We evaluated the performance of a strategy combining the both mentioned tools to detect directly from clinical samples, in 8 days, MTBC and its resistance to 13 antiTB drugs, and identify potential transmission of strains from patient-to-patient. Using this approach, we screened 112 clinical samples (65 smear-negative) and 94 MTBC cultured strains. The sensitivity and the specificity of the GeneLEAD/Deeplex Myc-TB approach for MTBC detection were 79.3% and 100%, respectively. One hundred forty successful Deeplex Myc-TB results were obtained for 46 clinical samples and 94 strains, a total of 85.4% of which had a Deeplex Myc-TB susceptibility and resistance prediction consistent with phenotypic drug susceptibility testing (DST). Importantly, the Deeplex Myc-TB assay was able to detect 100% of the multidrug-resistant (MDR) MTBC tested. The lowest concordance rates were for pyrazinamide, ethambutol, streptomycin, and ethionamide (84.5%, 81.5%, 73%, and 55%, respectively) for which the determination of susceptibility or resistance is generally difficult with current tools. One of the main difficulties of Deeplex Myc-TB is to interpret the non-synonymous uncharacterized variants that can represent up to 30% of the detected single nucleotide variants. We observed a good level of concordance between Deeplex Myc-TB-spoligotyping and MIRU-VNTR despite a lower discriminatory power for spoligotyping. The median time to obtain complete results from clinical samples was 8 days (IQR 7–13) provided a high-throughput NGS sequencing platform was available. Our results highlight that the GeneLEAD/Deeplex Myc-TB approach could be a breakthrough in rapid diagnosis of MDR TB in routine practice.
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Affiliation(s)
- Isabelle Bonnet
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Vincent Enouf
- Plateforme de Microbiologie Mutualisée (P2M), Pasteur International Bioresources network (PIBnet), Institut Pasteur, Paris, France
| | - Florence Morel
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Vichita Ok
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Jérémy Jaffré
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Vincent Jarlier
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France
| | - Alexandra Aubry
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Jérôme Robert
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
| | - Wladimir Sougakoff
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Service de Bactériologie-Hygiène, Paris, France.,Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (CNR-MyRMA), Paris, France.,Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Unité Mixte de Recherche (UMR) 1135, Paris, France
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Systematic Review of Mutations Associated with Isoniazid Resistance Points to Continuing Evolution and Subsequent Evasion of Molecular Detection, and Potential for Emergence of Multidrug Resistance in Clinical Strains of Mycobacterium tuberculosis. Antimicrob Agents Chemother 2021; 65:AAC.02091-20. [PMID: 33361298 DOI: 10.1128/aac.02091-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/13/2020] [Indexed: 01/24/2023] Open
Abstract
Molecular testing is rapidly becoming an integral component of global tuberculosis (TB) control. Uncommon mechanisms of resistance escape detection by these platforms and undermine our ability to contain outbreaks. This article is a systematic review of published articles that reported isoniazid (INH) resistance-conferring mutations between September 2013 and December 2019. The genes katG, inhA, and fabG1, and the intergenic region oxyR'-ahpC were considered in this review. Fifty-two articles were included that described 9,306 clinical isolates (5,804 INH resistant [INHr] and 3,502 INH susceptible [INHs]) from 31 countries. The three most frequently mutated loci continue to be locus 315 of katG (katG315; n = 4,271), locus -15 of inhA (inhA-15; n = 787), and locus -8 of inhA (inhA-8; 106). However, the diagnostic value of inhA-8 is far lower than previously thought, as it only appears in 25 (0.4%) of the INHr isolates lacking the first two mutations. I catalogued 45 new loci (29 katG, nine inhA, and seven ahpC) associated with INH resistance and identified 59 loci (common to this and previous reviews) as a reliable basis for molecular diagnostics. Including all observed mutations provides a cumulative sensitivity of 85.6%. In 14.4% of resistant isolates, no mechanism of resistance was detected, making them likely to escape molecular detection, and in the case of INH monoresistance, likely to convert to multidrug-resistant TB (MDR-TB). Integrating the information cataloged in this study into current diagnostic tools is essential for combating the emergence of MDR-TB, and its exclusion can lead to an unintended selection against common mechanisms and to diversifying evolution. Observation of many low-frequency resistance-conferring mutations points to an advantage of whole-genome sequencing (WGS) for diagnostics. Finally, I provide five recommendations for future diagnostic platforms.
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Gopalaswamy R, Shanmugam S, Mondal R, Subbian S. Of tuberculosis and non-tuberculous mycobacterial infections - a comparative analysis of epidemiology, diagnosis and treatment. J Biomed Sci 2020; 27:74. [PMID: 32552732 PMCID: PMC7297667 DOI: 10.1186/s12929-020-00667-6] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/05/2020] [Indexed: 12/26/2022] Open
Abstract
Pulmonary diseases due to mycobacteria cause significant morbidity and mortality to human health. In addition to tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), recent epidemiological studies have shown the emergence of non-tuberculous mycobacteria (NTM) species in causing lung diseases in humans. Although more than 170 NTM species are present in various environmental niches, only a handful, primarily Mycobacterium avium complex and M. abscessus, have been implicated in pulmonary disease. While TB is transmitted through inhalation of aerosol droplets containing Mtb, generated by patients with symptomatic disease, NTM disease is mostly disseminated through aerosols originated from the environment. However, following inhalation, both Mtb and NTM are phagocytosed by alveolar macrophages in the lungs. Subsequently, various immune cells are recruited from the circulation to the site of infection, which leads to granuloma formation. Although the pathophysiology of TB and NTM diseases share several fundamental cellular and molecular events, the host-susceptibility to Mtb and NTM infections are different. Striking differences also exist in the disease presentation between TB and NTM cases. While NTM disease is primarily associated with bronchiectasis, this condition is rarely a predisposing factor for TB. Similarly, in Human Immunodeficiency Virus (HIV)-infected individuals, NTM disease presents as disseminated, extrapulmonary form rather than as a miliary, pulmonary disease, which is seen in Mtb infection. The diagnostic modalities for TB, including molecular diagnosis and drug-susceptibility testing (DST), are more advanced and possess a higher rate of sensitivity and specificity, compared to the tools available for NTM infections. In general, drug-sensitive TB is effectively treated with a standard multi-drug regimen containing well-defined first- and second-line antibiotics. However, the treatment of drug-resistant TB requires the additional, newer class of antibiotics in combination with or without the first and second-line drugs. In contrast, the NTM species display significant heterogeneity in their susceptibility to standard anti-TB drugs. Thus, the treatment for NTM diseases usually involves the use of macrolides and injectable aminoglycosides. Although well-established international guidelines are available, treatment of NTM disease is mostly empirical and not entirely successful. In general, the treatment duration is much longer for NTM diseases, compared to TB, and resection surgery of affected organ(s) is part of treatment for patients with NTM diseases that do not respond to the antibiotics treatment. Here, we discuss the epidemiology, diagnosis, and treatment modalities available for TB and NTM diseases of humans.
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Affiliation(s)
- Radha Gopalaswamy
- Department of Bacteriology, National Institute for Research in Tuberculosis, Chennai, India
| | - Sivakumar Shanmugam
- Department of Bacteriology, National Institute for Research in Tuberculosis, Chennai, India
| | - Rajesh Mondal
- Department of Bacteriology, National Institute for Research in Tuberculosis, Chennai, India
| | - Selvakumar Subbian
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States.
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Chumpa N, Kawkitinarong K, Rotcheewaphan S, Sawatpanich A, Petsong S, Tumwasorn S, Suwanpimolkul G. Evaluation of Anyplex™ II MTB/MDR kit's performance to rapidly detect isoniazid and rifampicin resistant Mycobacterium tuberculosis from various clinical specimens. Mol Biol Rep 2020; 47:2501-2508. [PMID: 32124172 DOI: 10.1007/s11033-020-05331-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/15/2020] [Indexed: 12/30/2022]
Abstract
To determine the accuracy of multiplex real-time PCR (Anyplex™ II MTB/MDR kit) in detecting Isoniazid (INH)- and Rifampin (RIF)-resistant Mycobacterium tuberculosis strains from various clinical specimens. The performance of Anyplex™ II MTB/MDR kit in detecting INH- and RIF-resistant M. tuberculosis compared to the conventional drug susceptibility tests by Mycobacterial Growth Indicator Tube (MGIT). A total of 430 clinical samples had positive results for M. tuberculosis from both Anyplex™ II MTB/MDR kit assay and mycobacterial cultures by MGIT method. When compared to MGITs, the sensitivity and specificity of Anyplex™ II MTB/MDR kit in detecting INH-resistant TB were 85.71% and 99.75%, respectively. For the detection of MDR-TB, the sensitivity and specificity of the test were 82.35% and 99.76%, respectively. The positive predictive values and negative predictive values to detect INH-resistant TB were 96.77% and 98.75%, respectively. Anyplex™ II MTB/MDR kit can be used to rapidly detect isoniazid and rifampicin resistances. It has a high sensitivity, specificity and PPV in detecting INH-resistant TB and MDR-TB. This test can be used as an alternative test to Xpert MTB/RIF because it can rapidly detect both INH-resistant TB and RIF-resistant TB.
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Affiliation(s)
- Nuntana Chumpa
- Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Kamon Kawkitinarong
- Division of Pulmonary and Critical Care, Department of Medicine, Faculty of Medicine, Chulalongkorn Hospital, Thai Red Cross Society, Bangkok, Thailand
- Tuberculosis Research Unit, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Suwatchareeporn Rotcheewaphan
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Ajcharaporn Sawatpanich
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Suthidee Petsong
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Somying Tumwasorn
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Gompol Suwanpimolkul
- Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand.
- Tuberculosis Research Unit, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
- Division of Infectious Disease, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand.
- Department of Medicine, Faculty of Medicine, Thai Red Cross Emerging Infectious Diseases Clinical Center, Chulalongkorn University, Bangkok, Thailand.
- Division of Infectious Diseases, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathum Wan, Bangkok, 10330, Thailand.
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Lee Y, Raviglione MC, Flahault A. Use of Digital Technology to Enhance Tuberculosis Control: Scoping Review. J Med Internet Res 2020; 22:e15727. [PMID: 32053111 PMCID: PMC7055857 DOI: 10.2196/15727] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/22/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023] Open
Abstract
Background Tuberculosis (TB) is the leading cause of death from a single infectious agent, with around 1.5 million deaths reported in 2018, and is a major contributor to suffering worldwide, with an estimated 10 million new cases every year. In the context of the World Health Organization’s End TB strategy and the quest for digital innovations, there is a need to understand what is happening around the world regarding research into the use of digital technology for better TB care and control. Objective The purpose of this scoping review was to summarize the state of research on the use of digital technology to enhance TB care and control. This study provides an overview of publications covering this subject and answers 3 main questions: (1) to what extent has the issue been addressed in the scientific literature between January 2016 and March 2019, (2) which countries have been investing in research in this field, and (3) what digital technologies were used? Methods A Web-based search was conducted on PubMed and Web of Science. Studies that describe the use of digital technology with specific reference to keywords such as TB, digital health, eHealth, and mHealth were included. Data from selected studies were synthesized into 4 functions using narrative and graphical methods. Such digital health interventions were categorized based on 2 classifications, one by function and the other by targeted user. Results A total of 145 relevant studies were identified out of the 1005 published between January 2016 and March 2019. Overall, 72.4% (105/145) of the research focused on patient care and 20.7% (30/145) on surveillance and monitoring. Other programmatic functions 4.8% (7/145) and electronic learning 2.1% (3/145) were less frequently studied. Most digital health technologies used for patient care included primarily diagnostic 59.4% (63/106) and treatment adherence tools 40.6% (43/106). On the basis of the second type of classification, 107 studies targeted health care providers (107/145, 73.8%), 20 studies targeted clients (20/145, 13.8%), 17 dealt with data services (17/145, 11.7%), and 1 study was on the health system or resource management. The first authors’ affiliations were mainly from 3 countries: the United States (30/145 studies, 20.7%), China (20/145 studies, 13.8%), and India (17/145 studies, 11.7%). The researchers from the United States conducted their research both domestically and abroad, whereas researchers from China and India conducted all studies domestically. Conclusions The majority of research conducted between January 2016 and March 2019 on digital interventions for TB focused on diagnostic tools and treatment adherence technologies, such as video-observed therapy and SMS. Only a few studies addressed interventions for data services and health system or resource management.
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Affiliation(s)
- Yejin Lee
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Global Studies Institute, University of Geneva, Geneva, Switzerland
| | - Mario C Raviglione
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Global Studies Institute, University of Geneva, Geneva, Switzerland.,Centre for Multidisciplinary Research in Health Science (MACH), Università di Milano, Milan, Italy
| | - Antoine Flahault
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Global Studies Institute, University of Geneva, Geneva, Switzerland
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Innovative and rapid antimicrobial susceptibility testing systems. Nat Rev Microbiol 2020; 18:299-311. [PMID: 32055026 DOI: 10.1038/s41579-020-0327-x] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2020] [Indexed: 12/21/2022]
Abstract
Antimicrobial resistance (AMR) is a major threat to human health worldwide, and the rapid detection and quantification of resistance, combined with antimicrobial stewardship, are key interventions to combat the spread and emergence of AMR. Antimicrobial susceptibility testing (AST) systems are the collective set of diagnostic processes that facilitate the phenotypic and genotypic assessment of AMR and antibiotic susceptibility. Over the past 30 years, only a few high-throughput AST methods have been developed and widely implemented. By contrast, several studies have established proof of principle for various innovative AST methods, including both molecular-based and genome-based methods, which await clinical trials and regulatory review. In this Review, we discuss the current state of AST systems in the broadest technical, translational and implementation-related scope.
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Advanced integrative sensing technologies for detection of drug-resistant tuberculosis in point-of-care settings. SENSORS INTERNATIONAL 2020. [DOI: 10.1016/j.sintl.2020.100036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Nguyen TNA, Anton-Le Berre V, Bañuls AL, Nguyen TVA. Molecular Diagnosis of Drug-Resistant Tuberculosis; A Literature Review. Front Microbiol 2019; 10:794. [PMID: 31057511 PMCID: PMC6477542 DOI: 10.3389/fmicb.2019.00794] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 03/28/2019] [Indexed: 11/13/2022] Open
Abstract
Drug-resistant tuberculosis is a global health problem that hinders the progress of tuberculosis eradication programs. Accurate and early detection of drug-resistant tuberculosis is essential for effective patient care, for preventing tuberculosis spread, and for limiting the development of drug-resistant strains. Culture-based drug susceptibility tests are the gold standard method for the detection of drug-resistant tuberculosis, but they are time-consuming and technically challenging, especially in low- and middle-income countries. Nowadays, different nucleic acid-based assays that detect gene mutations associated with resistance to drugs used to treat tuberculosis are available. These tests vary in type and number of targets and in sensitivity and specificity. In this review, we will describe the available molecular tests for drug-resistant tuberculosis detection and discuss their advantages and limitations.
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Affiliation(s)
- Thi Ngoc Anh Nguyen
- UMR MIVEGEC, Institute of Research for Development, Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, France.,Laboratory of Tuberculosis, Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam.,LMI Drug Resistance in South East Asia, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | | | - Anne-Laure Bañuls
- UMR MIVEGEC, Institute of Research for Development, Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, France.,LMI Drug Resistance in South East Asia, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Thi Van Anh Nguyen
- Laboratory of Tuberculosis, Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam.,LMI Drug Resistance in South East Asia, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
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Luukinen BV, Vuento R, Hirvonen JJ. Evaluation of two tuberculosis PCR assays for routine use in a clinical setting of low population and low tuberculosis prevalence. APMIS 2019; 127:462-467. [PMID: 30901113 DOI: 10.1111/apm.12947] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 03/14/2019] [Indexed: 11/28/2022]
Abstract
Today, there are numerous different molecular diagnostic assays for the detection of tuberculosis (TB), allowing the optimization of rapid detection of TB according to the clinical need. In this study, two high-throughput TB PCR assays with combined antimicrobial resistance detection, Anyplex™ II MTB/MDR (Seegene) and RealTime MTB + RealTime MTB RIF/INH Resistance (Abbott Molecular), were evaluated for routine use in a clinical setting of low population and low TB prevalence in Finland. The RealTime MTB assay was 100% concordant (22/22 positive, n = 169) with the reference methods (culture and Xpert MTB/RIF PCR assay, Cepheid). However, with a limitation of four separate PCR cycles per kit, the routine use in a low TB-prevalence setting would easily lead to wasting most of the RIF/INH Resistance reagents. The Anyplex™ II MTB/MDR assay usability was more adaptive to suit the clinical setting but the assay sensitivity was considerably lower (86%, 19/22 positive, n = 76) being closer to the sensitivity of smear microscopy. The findings of this study suggest that the evaluated high-throughput MTB/MDR assays are evidently suboptimal for routine use in a low population, low TB-prevalence setting. In addition, neither of the two assays covers non-tuberculous mycobacteria and could therefore not fully replace acid-fast staining as the initial screening method.
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Affiliation(s)
- Bruno Vincent Luukinen
- Department of Clinical Microbiology, Fimlab Laboratories Ltd., Tampere, Finland.,Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Risto Vuento
- Department of Clinical Microbiology, Fimlab Laboratories Ltd., Tampere, Finland
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Comparison of DNA extraction methods for drug susceptibility testing by allele-specific primer extension on a microsphere-based platform: Chelex-100 (in-house and commercialized) and MagPurix TB DNA Extraction Kit. J Microbiol Methods 2018; 152:105-108. [PMID: 30075237 DOI: 10.1016/j.mimet.2018.07.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/30/2018] [Accepted: 07/30/2018] [Indexed: 11/21/2022]
Abstract
Tuberculosis (TB), caused by infections of the Mycobacterium tuberculosis (MTB) complex, is the ninth leading cause of death worldwide, and several molecular approaches for MTB species identification and the detection of mutations associated with drug resistance have been developed to date. We previously developed a diagnostic assay for drug susceptibility testing that can detect mutations conferring resistance to anti-TB drugs using allele-specific primer extension on a microsphere-based platform for multiplex polymerase chain reaction. The aim of the present study was to optimize this diagnostic assay based on the evaluation of three methods for extracting mycobacterial DNA from clinical samples. Mycobacterial DNA of 81 samples was digested and decontaminated by N-acetyl-l-cysteine-2% NaOH and then extracted using three methods: "in-house" 5% Chelex-100 chelating resin, InstaGene Matrix, and MagPurix TB DNA Extraction Kit. The former two methods are manual extraction methods, whereas the MagPurix TB DNA Extraction Kit is an automated extraction method used with the MagPurix 12 s automated nucleic acid purification system. The extracted DNA was then subjected to our diagnostic assay, and the results were compared among methods. The magnetic bead method exhibited a higher extraction efficiency and resulted in greater diagnostic efficacy than the two resin-based methods with respect to both target gene detection and acid-fast bacilli smear grades. Therefore, the MagPurix TB DNA Extraction Kit is the optimal MTB DNA extraction method for our diagnostic assay of TB drug susceptibility testing.
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