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Chaturvedi M, Patel M, Tiwari A, Dwivedi N, Mondal DP, Srivastava AK, Dhand C. An insight to the recent advancements in detection of Mycobacterium tuberculosis using biosensors: A systematic review. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2024; 186:14-27. [PMID: 38052326 DOI: 10.1016/j.pbiomolbio.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 07/31/2023] [Accepted: 10/01/2023] [Indexed: 12/07/2023]
Abstract
Since ancient times, Tuberculosis (TB) has been a severe invasive illness that has been prevalent for thousands of years and is also known as "consumption" or phthisis. TB is the most common chronic lung bacterial illness in the world, killing over 2 million people each year, caused by Mycobacterium tuberculosis (MTB). As per the reports of WHO, in spite of technology advancements, the average rate of decline in global TB infections from 2000-2018 was only 1.6% per year, and the worldwide reduction in TB deaths was only 11%. In addition, COVID-19 pandemic has reversed years of global progress in tackling TB with fewer diagnosed cases. The majority of undiagnosed patients of TB are found in low- and middle-income countries where the GeneXpert MTB/RIF assay and sputum smear microscopy have been approved by the WHO as reference procedures for quickly detecting TB. Biosensors, like other cutting-edge technologies, have piqued researchers' interest since they offer a quick and accurate way to identify MTB. Modern integrated technologies allow for the rapid, low-cost, and highly precise detection of analytes in extremely little amounts of sample by biosensors. Here in this review, we outlined the severity of tuberculosis (TB) and the most recent developments in the biosensors sector, as well as their various kinds and benefits for TB detection. The review also emphasizes how widespread TB is and how it needs accurate diagnosis and effective treatment.
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Affiliation(s)
- Mansi Chaturvedi
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; School of Biomolecular Engineering & Biotechnology UTD RGPV, Bhopal, 462033, India
| | - Monika Patel
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Archana Tiwari
- School of Biomolecular Engineering & Biotechnology UTD RGPV, Bhopal, 462033, India
| | - Neeraj Dwivedi
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - D P Mondal
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Avanish Kumar Srivastava
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Chetna Dhand
- CSIR-Advanced Materials and Processes Research Institute, Hoshangabad Road, Bhopal, 462026, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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Dwivedi H, MacDonald K, Angaali N, Garrett S, Klein J, Savidge T, Jacobs MR, Good CE, Lauzardo M, Patil MA, Garner CD, Pincus DH. Multicenter matched-pair study comparing BACT/ALERT® MP reagent systems for the recovery of mycobacteria from specimens other than blood. Diagn Microbiol Infect Dis 2023; 107:115959. [PMID: 37536260 DOI: 10.1016/j.diagmicrobio.2023.115959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 03/29/2023] [Accepted: 04/16/2023] [Indexed: 08/05/2023]
Abstract
The BACT/ALERT® MP Reagent System is a broth culture medium for optimal detection and recovery of mycobacteria from clinical samples. The MP formulation was recently modified to improve detection and recovery times. A multicenter prospective matched pair study design was conducted to validate the performance of improved MP (MP-I) versus current MP (MP-C) bottles utilizing nonsterile and normally sterile samples, except blood, from patients suspected of having mycobacterial infections. A total of 1488 clinical samples were collected to obtain 212 mycobacteria samples by either or both MP culture bottles. MP-I and MP-C sensitivities were 86.6% and 81.4%, respectively, but the difference was not significant (P = 0.163) while specificities were 96.8% and 93.8%, respectively, and that difference was significant (P = 0.002). Overall recovery was 94.34% for MP-I and 88.68% for MP-C (recovery was 100% for both bottles with 52 seeded samples). Overall performance of MP-I was better than MP-C for sensitivity, specificity, and recovery.
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Affiliation(s)
- Hari Dwivedi
- Global Medical Affairs-Microbiology, BioMérieux, Inc., Hazelwood, MO, USA.
| | | | - Neelima Angaali
- Department of Microbiology, Nizam's Institute of Medical Sciences, Hyderabad, Telangana, India
| | - Sheri Garrett
- Clinical Affairs, BioMérieux, Inc., Hazelwood, MO, USA
| | - Jenna Klein
- R&D Microbiology, BioMérieux, Inc., Durham, NC, USA
| | - Theresa Savidge
- Mycobacteriology Laboratory, National Jewish Health, Denver, CO, USA
| | - Michael R Jacobs
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Caryn E Good
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Michael Lauzardo
- Department of Medicine, UF Emerging Pathogens Institute, Gainesville, FL, USA
| | - M A Patil
- Department of Microbiology, Nizam's Institute of Medical Sciences, Hyderabad, Telangana, India
| | - Cherilyn D Garner
- Global Medical Affairs-Microbiology, BioMérieux, Inc., Hazelwood, MO, USA
| | - David H Pincus
- Global Medical Affairs-Microbiology, BioMérieux, Inc., Hazelwood, MO, USA
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Bashford J, Flowers W, Haworth C, Ryan J, Cervi A, Dulayymi JRA, Mason PS, Plank A, Baird M, Floto A. Evaluation of a novel ELISA test using synthetic mycolic acid antigens for serodiagnosis of non-tuberculous mycobacterial (NTM) infections. Thorax 2023; 78:309-312. [PMID: 36627190 DOI: 10.1136/thorax-2022-218800] [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: 02/09/2022] [Accepted: 11/20/2022] [Indexed: 01/12/2023]
Abstract
The diagnosis of non-tuberculous mycobacteria (NTM) is a particular challenge in people with cystic fibrosis. Current standard diagnostic approaches rely on serial sputum culture, which is resource demanding, dependent on patient expectoration and may be compromised by excessive decontamination, conventional bacterial overgrowth and masking by concomitant oral and nebulised antibiotics. An alternative rapid, reliable and inexpensive diagnostic method is therefore urgently needed. Serum of patients with Mycobacterium abscessus infection and chronic suppurative lung disease without NTM infection was tested against an array of novel synthetic mycolic acids, identical or similar to natural components of mycobacterial cell walls, and glycopeptidolipid (GPL)-core antigen, which has previously been investigated in Mycobacterium avium pulmonary infection. Diagnostic accuracy of individual antigens and combination of various antigens were calculated. An ELISA using individual trehalose dimycolates and GPL-core antigen was able to effectively distinguish serum from infected and non-infected individuals with a specificity of 88% and a sensitivity of up to 88%, which increased to 88% sensitivity and 93% specificity by combining several antigens in the test. These results suggest synthetic mycolic acid antigens, used individually or in combination with GPL-core antigen could be successfully used to distinguish patients with M. abscessus infection from disease controls.
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Affiliation(s)
- Julia Bashford
- Cambridge Centre for Lung Infection, Royal Papworth Hospital NHS Trust, Cambridge, UK
| | - William Flowers
- Cambridge Centre for Lung Infection, Royal Papworth Hospital NHS Trust, Cambridge, UK.,Molecular Immunity Unit, Department of Medicine, University of Cambridge, Cambridge, UK
| | - Charles Haworth
- Cambridge Centre for Lung Infection, Royal Papworth Hospital NHS Trust, Cambridge, UK
| | - Judy Ryan
- Cambridge Centre for Lung Infection, Royal Papworth Hospital NHS Trust, Cambridge, UK.,Molecular Immunity Unit, Department of Medicine, University of Cambridge, Cambridge, UK
| | - Anna Cervi
- Diagnostig Ltd, MSParc, Gaerwen Anglesey, Wales, UK
| | - J R Al Dulayymi
- School of Natural Sciences, Bangor University, Bangor, Wales, UK
| | - Paul S Mason
- Diagnostig Ltd, MSParc, Gaerwen Anglesey, Wales, UK
| | - Ashley Plank
- Icon Cancer Foundation, Brisbane, Queensland, Australia
| | - Mark Baird
- Diagnostig Ltd, MSParc, Gaerwen Anglesey, Wales, UK
| | - Andres Floto
- Cambridge Centre for Lung Infection, Royal Papworth Hospital NHS Trust, Cambridge, UK .,Molecular Immunity Unit, Department of Medicine, University of Cambridge, Cambridge, UK
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Daley CL, Iaccarino JM, Lange C, Cambau E, Wallace RJ, Andrejak C, Böttger EC, Brozek J, Griffith DE, Guglielmetti L, Huitt GA, Knight SL, Leitman P, Marras TK, Olivier KN, Santin M, Stout JE, Tortoli E, van Ingen J, Wagner D, Winthrop KL. Treatment of Nontuberculous Mycobacterial Pulmonary Disease: An Official ATS/ERS/ESCMID/IDSA Clinical Practice Guideline. Clin Infect Dis 2020; 71:e1-e36. [PMID: 32628747 PMCID: PMC7768748 DOI: 10.1093/cid/ciaa241] [Citation(s) in RCA: 339] [Impact Index Per Article: 84.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/05/2020] [Indexed: 12/14/2022] Open
Abstract
Nontuberculous mycobacteria (NTM) represent over 190 species and subspecies, some of which can produce disease in humans of all ages and can affect both pulmonary and extrapulmonary sites. This guideline focuses on pulmonary disease in adults (without cystic fibrosis or human immunodeficiency virus infection) caused by the most common NTM pathogens such as Mycobacterium avium complex, Mycobacterium kansasii, and Mycobacterium xenopi among the slowly growing NTM and Mycobacterium abscessus among the rapidly growing NTM. A panel of experts was carefully selected by leading international respiratory medicine and infectious diseases societies (ATS, ERS, ESCMID, IDSA) and included specialists in pulmonary medicine, infectious diseases and clinical microbiology, laboratory medicine, and patient advocacy. Systematic reviews were conducted around each of 22 PICO (Population, Intervention, Comparator, Outcome) questions and the recommendations were formulated, written, and graded using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Thirty-one evidence-based recommendations about treatment of NTM pulmonary disease are provided. This guideline is intended for use by healthcare professionals who care for patients with NTM pulmonary disease, including specialists in infectious diseases and pulmonary diseases.
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Affiliation(s)
- Charles L Daley
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Jonathan M Iaccarino
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Christoph Lange
- Division of Clinical Infectious Diseases, Research Center Borstel, Borstel, Germany
- German Center for Infection Research (DZIF), Clinical Tuberculosis Unit, Borstel, Germany
- Respiratory Medicine & International Health, University of Lübeck, Lübeck, Germany
- Department of Medicine, Karolinska Institute, Stockholm, Sweden
| | - Emmanuelle Cambau
- National Reference Center for Mycobacteria and Antimycobacterial Resistance, APHP -Hôpital Lariboisière, Bacteriology; Inserm, University Paris Diderot, IAME UMR1137, Paris, France
| | - Richard J Wallace
- Mycobacteria/Nocardia Laboratory, Department of Microbiology, The University of Texas Health Science Center, Tyler, Texas, USA
| | - Claire Andrejak
- Respiratory and Intensive Care Unit, University Hospital Amiens, Amiens, France
- EA 4294, AGIR, Jules Verne Picardy University, Amiens, France
| | - Erik C Böttger
- Institute of Medical Microbiology, National Reference Center for Mycobacteria, University of Zurich, Zurich, Switzerland
| | - Jan Brozek
- Department of Clinical Epidemiology & Biostatistics, McMaster University Health Sciences Centre, Hamilton, Ontario, Canada
| | - David E Griffith
- Pulmonary Infectious Disease Section, University of Texas Health Science Center, Tyler, Texas, USA
| | - Lorenzo Guglielmetti
- National Reference Center for Mycobacteria and Antimycobacterial Resistance, APHP -Hôpital Lariboisière, Bacteriology; Inserm, University Paris Diderot, IAME UMR1137, Paris, France
- Team E13 (Bactériologie), Centre d’Immunologie et des Maladies Infectieuses, Sorbonne Université, Université Pierre et Marie Curie, Université Paris 06, Centre de Recherche 7, INSERM, IAME UMR1137, Paris, France
| | - Gwen A Huitt
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Shandra L Knight
- Library and Knowledge Services, National Jewish Health, Denver, Colorado, USA
| | | | - Theodore K Marras
- Department of Medicine, University of Toronto and University Health Network, Toronto, Ontario, Canada
| | - Kenneth N Olivier
- Pulmonary Branch, National Heart, Lung and Blood Institute, Bethesda, Maryland, USA
| | - Miguel Santin
- Service of Infectious Diseases, Bellvitge University Hospital-IDIBELL, University of Barcelona, L’Hospitalet de Llobregat, Barcelona, Spain
| | - Jason E Stout
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina, USA
| | - Enrico Tortoli
- Emerging Bacterial Pathogens Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Jakko van Ingen
- Radboud Center for Infectious Diseases, Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dirk Wagner
- Division of Infectious Diseases, Department of Medicine II, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kevin L Winthrop
- Divisions of Infectious Diseases, Schools of Public Health and Medicine, Oregon Health and Science University, Portland, Oregon, USA
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5
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Daley CL, Iaccarino JM, Lange C, Cambau E, Wallace RJ, Andrejak C, Böttger EC, Brozek J, Griffith DE, Guglielmetti L, Huitt GA, Knight SL, Leitman P, Marras TK, Olivier KN, Santin M, Stout JE, Tortoli E, van Ingen J, Wagner D, Winthrop KL. Treatment of nontuberculous mycobacterial pulmonary disease: an official ATS/ERS/ESCMID/IDSA clinical practice guideline. Eur Respir J 2020; 56:2000535. [PMID: 32636299 PMCID: PMC8375621 DOI: 10.1183/13993003.00535-2020] [Citation(s) in RCA: 343] [Impact Index Per Article: 85.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 12/28/2022]
Abstract
Nontuberculous mycobacteria (NTM) represent over 190 species and subspecies, some of which can produce disease in humans of all ages and can affect both pulmonary and extrapulmonary sites. This guideline focuses on pulmonary disease in adults (without cystic fibrosis or human immunodeficiency virus infection) caused by the most common NTM pathogens such as Mycobacterium avium complex, Mycobacterium kansasii, and Mycobacterium xenopi among the slowly growing NTM and Mycobacterium abscessus among the rapidly growing NTM. A panel of experts was carefully selected by leading international respiratory medicine and infectious diseases societies (ATS, ERS, ESCMID, IDSA) and included specialists in pulmonary medicine, infectious diseases and clinical microbiology, laboratory medicine, and patient advocacy. Systematic reviews were conducted around each of 22 PICO (Population, Intervention, Comparator, Outcome) questions and the recommendations were formulated, written, and graded using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Thirty-one evidence-based recommendations about treatment of NTM pulmonary disease are provided. This guideline is intended for use by healthcare professionals who care for patients with NTM pulmonary disease, including specialists in infectious diseases and pulmonary diseases.
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Affiliation(s)
- Charles L. Daley
- National Jewish Health and University of Colorado Health
Sciences, Denver, Colorado, USA
| | | | - Christoph Lange
- Division of Clinical Infectious Diseases, Research Center
Borstel, Borstel, Germany, German Center for Infection Research (DZIF), Respiratory
Medicine & International Health, University of Lübeck, Lübeck,
Germany, and Dept of Medicine, Karolinska Institute, Stockholm, Sweden
| | - Emmanuelle Cambau
- National Reference Center for Mycobacteria and
Antimycobacterial Resistance, APHP -Hôpital Lariboisière,
Bacteriology; Inserm University Paris Diderot, IAME UMR1137, Bacteriology, Paris,
France
| | - Richard J. Wallace
- Mycobacteria/Nocardia Laboratory, Dept of Microbiology, The
University of Texas Health Science Center, Tyler, TX, USA
| | - Claire Andrejak
- Respiratory and Intensive Care Unit, University Hospital
Amiens, Amiens, France and EA 4294, AGIR, Jules Verne Picardy University, Amiens,
France
| | - Erik C. Böttger
- Institute of Medical Microbiology, National Reference
Center for Mycobacteria, University of Zurich, Zurich, Switzerland
| | - Jan Brozek
- Department of Clinical Epidemiology & Biostatistics,
McMaster University Health Sciences Centre, 1200 Main Street West, Hamilton, ON L8N
3Z5 Canada
| | - David E. Griffith
- Pulmonary Infectious Disease Section, University of Texas
Health Science Center, Tyler, TX, USA
| | - Lorenzo Guglielmetti
- National Reference Center for Mycobacteria and
Antimycobacterial Resistance, APHP -Hôpital Lariboisière,
Bacteriology; Inserm University Paris Diderot, IAME UMR1137, Bacteriology, Paris,
France
- Team E13 (Bactériologie), Centre
d’Immunologie et des Maladies Infectieuses, Sorbonne Université,
Université Pierre et Marie Curie, Université Paris 06, Centre de
Recherche 7, INSERM, IAME UMR1137, Paris, Francis
| | - Gwen A. Huitt
- Library and Knowledge Services, National Jewish Health,
Denver, Colorado, USA
| | - Shandra L. Knight
- Library and Knowledge Services, National Jewish Health,
Denver, Colorado, USA
| | | | - Theodore K. Marras
- Dept of Medicine, University of Toronto and University
Health Network, Toronto, ON, Canada
| | - Kenneth N. Olivier
- Pulmonary Branch, National Heart, Lung and Blood
Institute, Bethesda, MD, USA
| | - Miguel Santin
- Service of Infectious Diseases, Bellvitge University
Hospital-IDIBELL, University of Barcelona, L’Hospitalet de Llobregat,
Barcelona, Spain
| | - Jason E. Stout
- Division of Infectious Diseases and International Health,
Duke University Medical Center, Durham, NC, USA
| | - Enrico Tortoli
- Emerging Bacterial Pathogens Unit, IRCCS San Raffaele
Scientific Institute, Milan, Italy
| | - Jakko van Ingen
- Radboud Center for Infectious Diseases, Dept of Medical
Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dirk Wagner
- Division of Infectious Diseases, Dept of Medicine II,
Medical Center - University of Freiburg, Faculty of Medicine, University of
Freiburg, Freiburg, Germany
| | - Kevin L. Winthrop
- Divisions of Infectious Diseases, Schools of Public
Health and Medicine, Oregon Health and Science University, Portland, OR, USA
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Santin M, Barrabeig I, Malchair P, Gonzalez-Luquero L, Benitez MA, Sabria J, Palau-Benavent M, Cañete C, Lloret-Queraltó JA, Grijota-Camino MD, Dorca J, Alcaide F. Pulmonary Infections with Nontuberculous Mycobacteria, Catalonia, Spain, 1994-2014. Emerg Infect Dis 2019; 24:1091-1094. [PMID: 29774836 PMCID: PMC6004863 DOI: 10.3201/eid2406.172095] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
In Spain, systematic reporting of pulmonary infections with nontuberculous mycobacteria is not mandatory. Therefore, to determine trends, we retrospectively identified cases for January 1994–December 2014 in Catalonia. Over the 21 years, prevalence increased and was associated with being male. Mycobacterium avium complex and M. abscessus prevalence increased; M. kansasii prevalence decreased.
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Shibabaw A, Gelaw B, Kelley H, Balada-Llasat JM, Evans C, Wang SH, Torrelles JB, Tessema B. Accuracy of the color plate micro-colony detection for the diagnosis of Mycobacterium tuberculosis complex in Northwest Ethiopia. Tuberculosis (Edinb) 2019; 114:54-60. [PMID: 30711158 DOI: 10.1016/j.tube.2018.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 11/18/2018] [Accepted: 11/25/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Accurate and timely tuberculosis diagnosis is the primary step for initiating effective treatment. The color plate agar-based culture test (TB-CX test) is low cost, simple to use and detects Mycobacterium tuberculosis faster. Therefore, the main objective of this study was to compare the diagnostic accuracy and time to detection of positive cultures using color test and Lӧwenstein Jensen culture. METHODS A comparative cross-sectional study was conducted at University of Gondar Hospital. A total of 200 sputum samples were collected from TB patients and processed for direct smear microscopy and cultures. RESULTS Sixty-five percent were found positive on both methods and 4 (2%) were positive on LJ culture and negative on the color plate. The median time for detection of MTB growth was significantly shorter using color plate test (Median 12 days) than LJ culture (Median 21 days) (P < 0.0001). The overall sensitivity and specificity of the color test compared to LJ culture were 97% (95% CI: 93-99) and 100% (95% CI: 94-100), respectively. CONCLUSIONS The color plate test for micro-colonies allows early and accurate MTB diagnosis in a median time of 12 days. This rapid method could be an option for diagnosis of pulmonary TB in resource limited settings.
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Affiliation(s)
- Agumas Shibabaw
- Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
| | - Baye Gelaw
- Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Holden Kelley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | | | - Carlton Evans
- The Wellcome Centre for Clinical Tropical Medicine, Imperial College of London, London, United Kingdom
| | - Shu-Hua Wang
- Department of Internal Medicine, Division of Infectious Diseases, College of Medicine, The Ohio State University, Columbus, OH, USA
| | | | - Belay Tessema
- Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Performance of GenoType ® MTBDRplus assay in the diagnosis of drug-resistant tuberculosis in Tangier, Morocco. J Glob Antimicrob Resist 2017; 12:63-67. [PMID: 28899805 DOI: 10.1016/j.jgar.2017.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/28/2017] [Accepted: 09/02/2017] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES In Morocco, tuberculosis (TB) is a major public health problem with high morbidity and mortality. The main problem faced by the national TB programme is the high rate of drug-resistant (DR), particularly multi-drug resistant (MDR) strains. Diagnosis of DR-TB is mainly performed by conventional techniques that are time consuming with limited efficacy. In 2014, the GenoType® MTBDRplus assay was introduced in Morocco for drug susceptibility testing (DST). In this regard, the present study was planned to assess the diagnostic accuracy of the GenoType® MTBDRplus assay. METHODS A total of 70 samples from suspected TB cases in Tangier (Morocco) were analysed by conventional DST and GenoType® MTBDRplus assay. RESULTS Among the 70 samples, 37.1% were MDR, whereas monoresistance to isoniazid (INH) and rifampicin (RIF) was detected in 186% and 17.1% of strains, respectively, by DST. Using the GenoType® MTBDRplus approach, 12 isolates (17.1%) were identified as INH monoresistant, 9 (12.9%) as RIF monoresistant and 26 (37.1%) as MDR. rpoB531 and katG315 mutations were the most common mutations associated with resistance to RIF and INH, respectively. Significantly, all phenotypically MDR strains were also MDR by GenoType® MTBDRplus. The sensitivity of GenoType® MTBDRplus was 92.1% for RIF resistance and 97.4% for INH resistance, whereas the specificity was 100% for the two tested drugs. CONCLUSIONS GenoType® MTBDRplus assay is a rapid, reliable and accurate tool for the detection of DR-TB in clinical specimens. Its routine use will be of a great interest to prevent the dissemination of DR-TB in the community.
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Alcaide F, Peña MJ, Pérez-Risco D, Camprubi D, Gonzalez-Luquero L, Grijota-Camino MD, Dorca J, Santin M. Increasing isolation of rapidly growing mycobacteria in a low-incidence setting of environmental mycobacteria, 1994-2015. Eur J Clin Microbiol Infect Dis 2017; 36:1425-1432. [PMID: 28321580 DOI: 10.1007/s10096-017-2949-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/23/2017] [Indexed: 11/25/2022]
Abstract
To determine trends in incidence and clinical relevance of rapidly growing mycobacteria (RGM) in a low-prevalence region of non-tuberculous mycobacteria. We retrospectively identified all patients with RGM-positive cultures between January 1994 and December 2015. Trends in incidence, clinical significance, and outcomes were assessed. One hundred and forty patients had RGM-positive cultures (116 respiratory and 24 extra-respiratory sources). The incidence of RGM isolates increased steadily from 2003 (0.34 per 100,000) to 2015 (1.73 per 100,000), with an average annual increase of 8.3%. Thirty-two patients (22.9%) had clinical disease, which trended to cluster in the second half of the study period. A positive acid-fast bacilli smear (odds ratio [OR] 97.7, 95 % CI 13.8-689.4), the presence of extra-respiratory isolates (OR 19.4, 95 % CI 5.2-72.7), and female gender (OR 5.9, 95 % CI 1.9-19.1) were independently associated with clinical disease. Cure rates were 73.3 and 87.5% for pulmonary and extra-pulmonary disease respectively. Although the burden of disease remains low, the presence of RGM isolates is increasing in our geographical setting. Whether this rise will be sustained over time and will coincide with an increase in clinical disease, or whether it is merely a cycle in the poorly understood epidemiological behaviour of environmental mycobacteria, will be seen in the near future.
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Affiliation(s)
- F Alcaide
- Service of Microbiology, Bellvitge University Hospital-IDIBELL, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
- University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - M J Peña
- Service of Microbiology, Bellvitge University Hospital-IDIBELL, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - D Pérez-Risco
- Service of Microbiology, Bellvitge University Hospital-IDIBELL, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - D Camprubi
- Service of Infectious Diseases, Bellvitge University Hospital-IDIBELL, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - L Gonzalez-Luquero
- Service of Infectious Diseases, Bellvitge University Hospital-IDIBELL, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - M D Grijota-Camino
- Service of Infectious Diseases, Bellvitge University Hospital-IDIBELL, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - J Dorca
- Service of Pneumology, Bellvitge University Hospital-IDIBELL, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
- University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - M Santin
- Service of Infectious Diseases, Bellvitge University Hospital-IDIBELL, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain.
- University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain.
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10
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Abstract
ABSTRACT
The laboratory, which utilizes some of the most sophisticated and rapidly changing technologies, plays a critical role in the diagnosis of tuberculosis. Some of these tools are being employed in resource-challenged countries for the rapid detection and characterization of
Mycobacterium tuberculosis
. Foremost, the laboratory defines appropriate specimen criteria for optimal test performance. The direct detection of mycobacteria in the clinical specimen, predominantly done by acid-fast staining, may eventually be replaced by rapid-cycle PCR. The widespread use of the Xpert MTB/RIF (Cepheid) assay, which detects both
M. tuberculosis
and key genetic determinants of rifampin resistance, is important for the early detection of multidrug-resistant strains. Culture, using both broth and solid media, remains the standard for establishing the laboratory-based diagnosis of tuberculosis. Cultured isolates are identified far less commonly by traditional biochemical profiling and more commonly by molecular methods, such as DNA probes and broad-range PCR with DNA sequencing. Non-nucleic acid-based methods of identification, such as high-performance liquid chromatography and, more recently, matrix-assisted laser desorption/ionization–time of flight mass spectrometry, may also be used for identification. Cultured isolates of
M. tuberculosis
should be submitted for susceptibility testing according to standard guidelines. The use of broth-based susceptibility testing is recommended to significantly decrease the time to result. Cultured isolates may also be submitted for strain typing for epidemiologic purposes. The use of massive parallel sequencing, also known as next-generation sequencing, promises to continue to this molecular revolution in mycobacteriology, as whole-genome sequencing provides identification, susceptibility, and typing information simultaneously.
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Khan SU, Rahman H, Ayaz S, Qasim M, Jabbar A, Khurshid M, Hussain M, Muhammad N, Rehman SU, Ali N. GeneXpert assay for rapid detection of Mycobacterium tuberculosis complex in respiratory specimens from a high TB endemic area of Pakistan. Microb Pathog 2016; 95:82-85. [DOI: 10.1016/j.micpath.2016.03.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 03/15/2016] [Accepted: 03/22/2016] [Indexed: 11/28/2022]
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Abstract
Tuberculosis (TB), caused byMycobacterium tuberculosis(M.tb.), is one of the most prevalent and serious infectious diseases worldwide with an estimated annual global mortality of 1.4 million in 2010.
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Affiliation(s)
- Saurabh K. Srivastava
- Plant Research International
- Wageningen UR
- 6708 PB Wageningen
- The Netherlands
- Laboratory of Organic Chemistry
| | - Cees J. M. van Rijn
- Laboratory of Organic Chemistry
- Wageningen UR
- 6703 HB Wageningen
- The Netherlands
| | - Maarten A. Jongsma
- Plant Research International
- Wageningen UR
- 6708 PB Wageningen
- The Netherlands
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Arora J, Kumar G, Verma AK, Bhalla M, Sarin R, Myneedu VP. Utility of MPT64 Antigen Detection for Rapid Confirmation of Mycobacterium tuberculosis Complex. J Glob Infect Dis 2015; 7:66-9. [PMID: 26069425 PMCID: PMC4448327 DOI: 10.4103/0974-777x.154443] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background: Rapid differentiation of the Mycobacterium tuberculosis complex (MTBC) and mycobacteria other than tuberculosis (MOTT) is crucial to facilitate early and effective treatment of the patients. Clinical presentation of MTBC and MOTT is not always very clear and routine conventional methods are time consuming. Materials and Methods: In the present study, the MPT64 protein detection-based immunochomatographic test (SD Bioline Kit, Standard Diagnostics, Inc., Korea) was compared with the conventional biochemical method. Results: The sensitivity, specificity, positive predictive, and negative predictive values of the SD AgMPT64 kit were found to be 100, 96.4, 98.72, and 100%, respectively. Conclusions: Our results have demonstrated that the SD bioline kit is a rapid, reliable method and it can be used in the Revised National Tuberculosis Control Program (RNTCP) of India, for the appropriate management of tuberculosis.
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Affiliation(s)
- Jyoti Arora
- Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
| | - Gavish Kumar
- Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
| | - Ajoy Kumar Verma
- Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
| | - Manpreet Bhalla
- Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
| | - Rohit Sarin
- Department of TB and Chest, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
| | - Vithal Prasad Myneedu
- Department of Microbiology, National Institute of Tuberculosis and Respiratory Diseases, Sri Aurobindo Marg, New Delhi, India
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Abstract
Pulmonary disease is by far the most frequent disease caused by nontuberculous mycobacteria (NTM). To diagnose NTM pulmonary disease (NTM-PD), patients should have symptoms and radiologic signs suggestive of NTM-PD, and cultures of multiple respiratory tract samples must grow the same NTM species. Thus, the microbiological laboratory has a central role in the diagnosis of NTM-PD. This review summarizes currently available data on techniques involved in the microbiological diagnosis of NTM-PD, and aims to provide a framework for optimal microbiological diagnosis.
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Specific amplification of gene encoding N-terminal region of catalase-peroxidase protein (KatG-N) for diagnosis of disseminated MAC disease in HIV patients. Diagn Microbiol Infect Dis 2014; 80:122-9. [PMID: 25070007 DOI: 10.1016/j.diagmicrobio.2014.06.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 06/16/2014] [Accepted: 06/18/2014] [Indexed: 11/20/2022]
Abstract
Disseminated Mycobacterium avium-intracellulare complex (MAC) infection is considered as severe complication of advanced HIV/AIDS disease. Currently available various laboratory investigations have not only limited ability to discriminate between MAC infection and tuberculosis but are also laborious and time consuming. The aim of this study was, therefore, to design a molecular-based strategy for specific detection of MAC and its differentiation from Mycobacterium tuberculosis (M. tb) isolated from the blood specimens of HIV patients. A simple PCR was developed based on the amplification of 120-bp katG-N gene corresponding to the first 40 amino acids of N-terminal catalase-peroxidase (KatG) protein of Mycobacterium avium that shows only ~13% sequence homology by clustal W alignment to N-terminal region of M. tb KatG protein. This assay allowed the accurate and rapid detection of MAC bacteremia, distinguishing it from M. tb in a single PCR reaction without any need for sequencing or hybridization protocol to be performed thereafter. This study produced enough evidence that a significant proportion of Indian HIV patients have disseminated MAC bacteremia, suggesting the utility of M. avium katG-N gene PCR for early detection of MAC disease in HIV patients.
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Hasan M, Munshi SK, Banu Momi MS, Rahman F, Noor R. Evaluation of the effectiveness of BACTEC MGIT 960 for the detection of mycobacteria in Bangladesh. Int J Mycobacteriol 2013; 2:214-9. [PMID: 26786125 DOI: 10.1016/j.ijmyco.2013.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 08/23/2013] [Accepted: 09/05/2013] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Tuberculosis (TB) caused by Mycobacterium tuberculosis has been identified as a re-emerging infectious disease with public health importance globally. Exploitation of new laboratory techniques for precise identification of mycobacteria in clinical specimens is of great importance to improve the diagnosis as part of the global TB control efforts. METHODS The current study was conducted for the evaluation of BACTEC MGIT 960 method in comparison with Lowenstein-Jensen (LJ) culture and light emitting diode (LED) fluorescence microscopy for isolation of mycobacteria among TB suspects from Bangladesh. A total of 421 specimens were tested with these methods. RESULTS Among the tested samples, 3.6% (n=15) were LED fluorescence microscopy positive; while 18 (4.2%) and 45 (10.6%) were recovered from LJ and MGIT 960 culture. The relative positivity found through MGIT 960 system were 60% and 66.7% higher than that of LJ culture and LED fluorescence microscopy, respectively. Recovery rate of Mycobacterium tuberculosis complex ([MTC], 21 by MGIT and 16 by LJ culture) and non-tubercular mycobacteria ([NTM], 24 by MGIT and 2 by LJ culture) by MGIT 960 was 24% and 96% greater, respectively than LJ culture. Moreover, MGIT 960 was found to be highly sensitive (100%), specific (93.3%), accurate (93.6%) and a more rapid method in detecting mycobacteria when compared with LJ culture. CONCLUSION Extended recovery of NTM and MTC through MGIT 960 urged frequent application of this method to detect mycobacteria more effectively and rapidly.
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Affiliation(s)
- Mehedi Hasan
- Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka 1217, Bangladesh; Mycobacteriology Laboratory, International Centre for Diarrheal Disease Research, Bangladesh (icdddr,b), Mohakhali, Dhaka 1212, Bangladesh.
| | - Saurab Kishore Munshi
- Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka 1217, Bangladesh.
| | - Mst Sabiha Banu Momi
- Mycobacteriology Laboratory, International Centre for Diarrheal Disease Research, Bangladesh (icdddr,b), Mohakhali, Dhaka 1212, Bangladesh.
| | - Farjana Rahman
- Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka 1217, Bangladesh.
| | - Rashed Noor
- Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka 1217, Bangladesh.
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Characterization of multi-drug resistant Mycobacterium tuberculosis from immigrants residing in the USA using Ion Torrent full-gene sequencing. Epidemiol Infect 2013; 142:1328-33. [PMID: 24073633 PMCID: PMC4045166 DOI: 10.1017/s0950268813002409] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SUMMARY Drug-resistant Mycobacterium tuberculosis bacterium (MTB) is spreading worldwide. Three drug-resistant isolates were detected in Burmese, Hmong, and Indian immigrants currently residing in Milwaukee, Wisconsin, USA. Ion Torrent full-gene sequencing and complete genetic analysis was performed within 5 days and compared to results from traditional drug sensitivity testing (DST). Genetic characterization of seven, full-length resistance-associated genes revealed two MDR and one highly resistant strain with important drug-resistant mutations that were confirmed by traditional DST. The rapid turnaround from sample-to-sequence underscores the public health value of Ion Torrent full-gene sequencing of MDR/XDR genes from epidemiologically significant clinical isolates.
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Kim CJ, Kim NH, Song KH, Choe PG, Kim ES, Park SW, Kim HB, Kim NJ, Kim EC, Park WB, Oh MD. Differentiating rapid- and slow-growing mycobacteria by difference in time to growth detection in liquid media. Diagn Microbiol Infect Dis 2012; 75:73-6. [PMID: 23114094 DOI: 10.1016/j.diagmicrobio.2012.09.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 10/27/2022]
Abstract
Nontuberculous mycobacteria (NTM) are classified into 2 categories: slow-growing mycobacteria (SGM) and rapid-growing mycobacteria (RGM), based on interval to colony formation by subculture on solid media. However, little is known about the growth rate of NTM in liquid broth media. We evaluated the differences in time to growth detection (TGD) of RGM and SGM in liquid broth media according to acid-fast stain. Among the 696 NTM isolates, 201 were RGM and 495 were SGM. In acid-fast bacilli (AFB)-negative specimens, the mean TGD was 133 h for RGM and 269 h for SGM (P < 0.001). In AFB-positive specimens, the mean TGD was 112 ± 37 h for RGM and 155 ± 125 h for SGM (P = 0.063). In the AFB-negative group, a cut-off value of 6 days was most effective for distinguishing SGM from RGM; however, in the AFB-positive group, an appropriate cut-off value was hard to define with TGD only.
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Affiliation(s)
- Chung-Jong Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744, Republic of Korea
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Patel K, Jhamb SS, Singh PP. Models of latent tuberculosis: their salient features, limitations, and development. J Lab Physicians 2012; 3:75-9. [PMID: 22219558 PMCID: PMC3249721 DOI: 10.4103/0974-2727.86837] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Latent tuberculosis is a subclinical condition caused by Mycobacterium tuberculosis, which affects about one-third of the population across the world. To abridge the chemotherapy of tuberculosis, it is necessary to have active drugs against latent form of M. tuberculosis. Therefore, it is imperative to devise in vitro and models of latent tuberculosis to explore potential drugs. In vitro models such as hypoxia, nutrient starvation, and multiple stresses are based on adverse conditions encountered by bacilli in granuloma. Bacilli experience oxygen depletion condition in hypoxia model, whereas the nutrient starvation model is based on deprivation of total nutrients from a culture medium. In the multiple stress model dormancy is induced by more than one type of stress. In silico mathematical models have also been developed to predict the interactions of bacilli with the host immune system and to propose structures for potential anti tuberculosis compounds. Besides these in vitro and in silico models, there are a number of in vivo animal models like mouse, guinea pig, rabbit, etc. Although they simulate human latent tuberculosis up to a certain extent but do not truly replicate human infection. All these models have their inherent merits and demerits. However, there is no perfect model for latent tuberculosis. Therefore, it is imperative to upgrade and refine existing models or develop a new model. However, battery of models will always be a better alternative to any single model as they will complement each other by overcoming their limitations.
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Affiliation(s)
- Kamlesh Patel
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Punjab, India
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Tyrrell FC, Budnick GE, Elliott T, Gillim-Ross L, Hildred MV, Mahlmeister P, Parrish N, Pentella M, Vanneste J, Wang YFW, Starks AM. Probability of negative mycobacterium tuberculosis complex cultures based on time to detection of positive cultures: a multicenter evaluation of commercial-broth-based culture systems. J Clin Microbiol 2012; 50:3275-82. [PMID: 22837326 PMCID: PMC3457445 DOI: 10.1128/jcm.01225-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 07/19/2012] [Indexed: 11/20/2022] Open
Abstract
We conducted a multicenter study to determine whether Mycobacterium tuberculosis complex (MTBC) cultures in automated broth-based systems could reliably be considered negative sooner than 6 weeks. Laboratory sites used Bactec MGIT or BacT/Alert and tracked results of time to detection of all mycobacteria (TTD-all, n = 1547) and of MTBC (TTD-MTBC, n = 466) over 6-month periods from primarily (93%) respiratory specimens. Cumulative percentages by day detected and median TTD of initial and follow-up specimens were analyzed. The median TTD-MTBC for MGIT (n = 6 sites) was 14 days. For laboratories using standard processing procedures, 100% of MTBC were detected from initial and follow-up specimens in 28 and 35 days, respectively, and no yield of MTBC on solid or MGIT liquid media was observed after 5 weeks. The median TTD-MTBC for BacT/Alert (n = 3 sites) was 18 days, with 95% and 100% detected within 37 and 42 days, respectively. Analysis of TTD of positive MTBC cultures in broth can predict the probability of culture negativity at defined time points. Receipt of interim negative reports earlier than 6 weeks could assist clinicians in considering alternative diagnoses and could alter the timing and prioritization of public health interventions. Laboratories should analyze their own TTD data to inform protocol decisions. Laboratories using MGIT could issue reports of no growth of MTBC on initial specimens as early as 4 weeks and for patients undergoing treatment as early as 5 weeks postinoculation.
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Grobler A, Levanets O, Whitney S, Booth C, Viljoen H. Rapid cell lysis and DNA capture in a lysis microreactor. Chem Eng Sci 2012. [DOI: 10.1016/j.ces.2012.07.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Growth detection failures by the nonradiometric Bactec MGIT 960 mycobacterial culture system. J Clin Microbiol 2012; 50:2092-5. [PMID: 22493332 DOI: 10.1128/jcm.00108-12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterial growth in liquid culture can go undetected by automated, nonradiometric growth detection systems. In our laboratory, instrument-negative tubes from the Bactec MGIT 960 system are inspected visually for clumps suggestive of mycobacterial growth, which (if present) are examined by acid-fast smear analysis. A 3-year review demonstrated that ∼1% of instrument-negative MGIT cultures contained mycobacterial growth and that 10% of all cultures yielding mycobacteria were instrument negative. Isolates from instrument-negative MGIT cultures included both tuberculous and nontuberculous mycobacteria.
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Lagrange PH, Thangaraj SK, Dayal R, Despande A, Ganguly NK, Girardi E, Joshi B, Katoch K, Katoch VM, Kumar M, Lakshmi V, Leportier M, Longuet C, Malladi SVS, Mukerjee D, Nair D, Raja A, Raman B, Rodrigues C, Sharma P, Singh A, Singh S, Sodha A, Kabeer BSA, Vernet G, Goletti D. A toolbox for tuberculosis diagnosis: an Indian multicentric study (2006-2008): microbiological results. PLoS One 2012; 7:e43739. [PMID: 22937088 PMCID: PMC3427157 DOI: 10.1371/journal.pone.0043739] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 07/23/2012] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The aim of this multicentric prospective study in India was to assess the value of several microbiological tools that contribute to the diagnosis of tuberculosis (TB) according to HIV status. METHODS Standard microbiological tools on individual specimens were analyzed. RESULTS Among the 807 patients with active TB, 131 were HIV-infected, 316 HIV-uninfected and 360 had HIV-unknown status. Among the 980 non-active TB subjects, 559 were at low risk and 421 were at high risk of M. tuberculosis (Mtb) exposure. Sensitivity of smear microscopy (SM) was significantly lower in HIV-infected (42.2%) than HIV-uninfected (75.9%) (p = 0.0001) and HIV-unknown pulmonary TB patients (61.4%) (p = 0.004). Specificity was 94.5% in non-TB patients and 100% in health care workers (HCW) and healthy family contacts. Automated liquid culture has significantly higher diagnostic performances than solid culture, measured by sensitivity (74.7% vs. 55.9%) (p = 0.0001) and shorter median time to detection (TTD) (12.0 vs. 34.0 days) (p = 0.0001). Specificity was 100% in HCW and cured-TB patients, but was lower in non-TB patients (89%) due to isolation of Mycobacteria other than tuberculosis (MOTT). TTD by both methods was related to AFB score. Contamination rate was low (1.4%). AccuProbe hybridization technique detected Mtb in almost all culture-positive specimens, but MOTT were found in 4.7% with a significantly higher frequency in HIV-infected (15%) than HIV-uninfected TB patients (0.5%) (p = 0.0007). Pre-test classification significantly increased the diagnostic value of all microbiological tests in pulmonary TB patients (p<0.0001) but to a lesser degree in extrapulmonary TB patients. CONCLUSIONS Conventional microbiological tools led to results similar to those already described in India special features for HIV-infected TB patients included lower detection by SM and culture. New microbiological assays, such as the automated liquid culture system, showed increased accuracy and speed of detection.
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Affiliation(s)
- Philippe H. Lagrange
- Service de Microbiologie, Hôpital Saint Louis, Assistance Publique- Hôpitaux de Paris, Paris VII Denis Diderot University, Paris, France
- * E-mail:
| | | | | | | | | | - Enrico Girardi
- Department of Epidemiology and Preclinical Research, L. Spallanzani National Institute for Infectious Diseases (INMI), Rome, Italy
| | - Beenu Joshi
- National JALMA Institute of Leprosy & Other Mycrobacterial Diseases (ICMR), Agra, India
| | - Kiran Katoch
- National JALMA Institute of Leprosy & Other Mycrobacterial Diseases (ICMR), Agra, India
| | - Vishwa M. Katoch
- National JALMA Institute of Leprosy & Other Mycrobacterial Diseases (ICMR), Agra, India
| | - Manoj Kumar
- All India Institute of Medical Sciences, New Delhi, India
| | - Vemu Lakshmi
- Nizam’s Institute of Medical Sciences, Hyderabad, India
| | - Marc Leportier
- bioMérieux, Marcy-l’Etoile, France, and New Delhi, India
| | | | | | | | | | - Alamelu Raja
- Tuberculosis Research Centre (TRC), ICMR, Cheput, Chennai, India
| | - Balambal Raman
- Tuberculosis Research Centre (TRC), ICMR, Cheput, Chennai, India
| | | | | | | | - Sarman Singh
- All India Institute of Medical Sciences, New Delhi, India
| | - Archana Sodha
- P.D. Hinduja National Hospital and Research Center, Mumbai, India
| | | | | | - Delia Goletti
- Department of Epidemiology and Preclinical Research, L. Spallanzani National Institute for Infectious Diseases (INMI), Rome, Italy
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Simultaneous identification of mycobacterial isolates to the species level and determination of tuberculosis drug resistance by PCR followed by electrospray ionization mass spectrometry. J Clin Microbiol 2010; 49:908-17. [PMID: 21191060 DOI: 10.1128/jcm.01578-10] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Mycobacterium tuberculosis that is resistant to both isoniazid (INH) and rifampin (RIF) is spreading. It has become a public health problem in part because the standard culture methods used to determine the appropriate treatment regimen for patients often take months following the presumptive diagnosis of tuberculosis. Furthermore, the misidentification of nontuberculosis mycobacteria (NTM) in patients presumably suffering from tuberculosis results in additional human and health care costs. The mechanisms of resistance for several drugs used to treat Mycobacterium tuberculosis are well understood and therefore should be amenable to determination by rapid molecular methods. We describe here the use of PCR followed by electrospray ionization mass spectrometry (PCR/ESI-MS) in an assay that simultaneously determines INH and RIF resistance in Mycobacterium tuberculosis and identifies and determines the species of NTMs. The assay panel included 16 primer pairs in eight multiplexed reactions and was validated using a collection of 1,340 DNA samples from cultured specimens collected in the New York City area, the Republic of Georgia, and South Africa. Compared with phenotypic data, the PCR/ESI-MS assay had 89.3% sensitivity and 95.8% specificity in the determination of INH resistance and 96.3% sensitivity and 98.6% specificity in the determination of RIF resistance. Based on a set of 264 previously characterized liquid culture specimens, the PCR/ESI-MS method had 97.0% sensitivity and 99.9% specificity for determination of NTM identity. The assay also provides information on ethambutol, fluoroquinolone, and diarylquinoline resistance and lineage-specific polymorphisms, to yield highly discriminative digital signatures potentially suitable for epidemiology tracking.
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Evaluation of the Capilia TB assay for culture confirmation of Mycobacterium tuberculosis infections in Zambia and South Africa. J Clin Microbiol 2010; 48:3773-5. [PMID: 20686084 DOI: 10.1128/jcm.01688-09] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The performance and cost of the Capilia TB assay were evaluated for use in a resource-limited setting. The sensitivity and specificity were 99.6% and 99.5%, respectively. The incremental costs of the Capilia test were estimated to be $1.46 and $1.84 when the test was added to liquid and solid culture processes, respectively. These findings suggest that the Capilia TB assay represents a rapid, simple, and inexpensive Mycobacterium tuberculosis identification test that can be used in resource-limited settings.
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Alcaide F. ¿Qué aporta la biología molecular al diagnóstico de la tuberculosis? Enferm Infecc Microbiol Clin 2009; 27:493-5. [DOI: 10.1016/j.eimc.2009.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 04/27/2009] [Accepted: 05/05/2009] [Indexed: 11/27/2022]
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Identification and differentiation of clinically relevant mycobacterium species directly from acid-fast bacillus-positive culture broth. J Clin Microbiol 2009; 47:3814-20. [PMID: 19794046 DOI: 10.1128/jcm.01534-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium species cause a variety of clinical diseases, some of which may be species specific. Therefore, it is clinically desirable to rapidly identify and differentiate mycobacterial isolates to the species level. We developed a rapid and high-throughput system, MycoID, to identify Mycobacterium species directly from acid-fast bacillus (AFB)-positive mycobacterial culture broth. The MycoID system incorporated broad-range PCR followed by suspension array hybridization to identify 17 clinically relevant mycobacterial complexes, groups, and species in one single reaction. We evaluated a total of 271 AFB-positive culture broth specimens, which were identified by reference standard methods in combination with biochemical and molecular tests. The overall identification agreement between the standard and the MycoID system was 89.7% (perfect match) or 97.8% (one match in codetection). In comparison to the standard, the MycoID system possessed an overall sensitivity of 97.1% and specificity of 98.8%. The 159 Mycobacterium avium-M. intracellulare complex isolates were further identified to the species level by MycoID as being M. avium (n = 98; 61.1%), M. intracellulare (n = 57; 35.8%), and mixed M. avium and M. intracellulare (n = 2; 1.3%). M. avium was recovered more frequently from sterile sites than M. intracellulare (odds ratio, 4.6; P = 0.0092). The entire MycoID procedure, including specimen processing, can be completed within 5 h, providing rapid and reliable identification and differentiation of mycobacterium species that is amenable to automation. Additional differentiation of Mycobacterium avium-M. intracellulare complex strains into M. avium and M. intracellulare may provide a tool to better understand the role of Mycobacterium avium-M. intracellulare complex isolates in human disease.
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Sun JR, Lee SY, Perng CL, Lu JJ. Detecting Mycobacterium tuberculosis in Bactec MGIT 960 cultures by inhouse IS6110-based PCR assay in routine clinical practice. J Formos Med Assoc 2009; 108:119-25. [PMID: 19251547 DOI: 10.1016/s0929-6646(09)60042-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND/PURPOSE Diagnosis of tuberculosis is challenging because the current methods are time-consuming and laborious. We have developed a method combining the Bactec MGIT 960 rapid culture system with the IS6110-based PCR for rapid diagnosis of tuberculosis. METHODS A total of 1745 samples from 712 patients treated at the Tri-Service General Hospital, Taipei, Taiwan between June and August 2005 were tested. An aliquot of positive Bactec MGIT 960 culture fluids was Kinyoun stained, and the samples positive for Kinyoun staining were directly assayed by the IS6110-based PCR. The same samples were also examined by the conventional methods for identification of Mycobacterium tuberculosis complex. RESULTS One hundred and four samples from 62 patients were positive according to the Bactec MGIT 960 system. Among these, 59 (56.7%) were positive and 45 (43.3%) were negative according to the IS6110-based PCR. Compared with the conventional identification methods, the IS6110-based PCR assay correctly identified all 59 M. tuberculosis isolates and gave negative results for all nontuberculosis mycobacteria. The mean turnaround time for M. tuberculosis identification by this combined method was 6.41 days for smear-positive and 14.33 days for smear-negative specimens. The sensitivity of the IS6110-based PCR assay was determined to be 5 cells or 0.1 pg of mycobacterial DNA. CONCLUSION The combined use of the automated Bactec MGIT 960 system and the IS6110-based PCR assay is sensitive and rapid for the detection of M. tuberculosis complex, and we recommend that this method be used routinely for identification of mycobacteria in clinical laboratories.
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Affiliation(s)
- Jun-Ren Sun
- Division of Clinical Pathology, Department of Pathology, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
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Comparison of the conventional culture, the manual fluorescent MGIT system and the automated fluorescent MGIT 960 culture system for the detection of Mycobacterium avium ssp. avium in tissues of naturally infected hens. Folia Microbiol (Praha) 2009; 54:137-41. [PMID: 19418251 DOI: 10.1007/s12223-009-0020-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 12/11/2008] [Indexed: 10/20/2022]
Abstract
Different methods for the detection of Mycobacterium avium ssp. avium (MAA) in naturally infected hens were compared. They included the conventional culture method (solid Herrold's and Stonebrink media and liquid Sula medium) and newly developed liquid culture systems, the manual mycobacteria growth indicator tube (M-MGIT) and the fully automated BACTEC MGIT 960 system (A-MGIT). 152 tissues originating from 15 naturally infected hens have been processed. The overall detection rates (percentage of positive cultures from the number of positive cultures determined by all the methods together) were 60, 70 and 76 % for the conventional media, M-MGIT and A-MGIT systems, respectively, the mean time of mycobacteria detection being 32.6, 17.6 and 14.6 d, respectively. The lowest contamination rate (2.0 %) was found in A-MGIT compared with M-MGIT (4.6 %) and conventional media (10.4 %).
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30
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Comparaison du milieu mycobacteria growth indicator tube et des milieux solides pour l’isolement des mycobactéries du complexe tuberculosis à partir d’hémocultures. ACTA ACUST UNITED AC 2009; 57:44-50. [DOI: 10.1016/j.patbio.2008.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Accepted: 05/16/2008] [Indexed: 11/23/2022]
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31
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Parrish N, Dionne K, Sweeney A, Hedgepeth A, Carroll K. Differences in time to detection and recovery of Mycobacterium spp. between the MGIT 960 and the BacT/ALERT MB automated culture systems. Diagn Microbiol Infect Dis 2009; 63:342-5. [PMID: 19168305 DOI: 10.1016/j.diagmicrobio.2008.11.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 10/31/2008] [Accepted: 11/20/2008] [Indexed: 11/17/2022]
Abstract
Mycobacterium sp. recovery and time to detection were compared in the MGIT 960 and BacT/ALERT MB automated broth culture systems. The MGIT 960 demonstrated shorter time to detection (13.5 versus 25.2 days) and greater sensitivity (100% versus 66.6%) for recovery of the Mycobacterium tuberculosis complex than the BacT/ALERT MB system.
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Affiliation(s)
- Nicole Parrish
- The Johns Hopkins Medical Institutions, Baltimore, MD 21287, USA.
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32
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Unreliable detection of Mycobacterium xenopi by the nonradiometric Bactec MGIT 960 culture system. J Clin Microbiol 2009; 47:804-6. [PMID: 19144802 DOI: 10.1128/jcm.01444-08] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
From June 2006 to December 2007, 3,648 clinical specimens consecutively received for mycobacterial culture were investigated. Each processed sample was inoculated into Bactec MGIT 960 liquid medium and a Löwenstein-Jensen slant. Tubes that were flagged as positive by the instrument as well as those determined to be negative after 42 days of incubation were removed, visually inspected for growth, and checked for the presence of acid-fast bacilli. Three hundred sixty-nine mycobacterial strains were recovered; of the 44 Mycobacterium xenopi isolates recovered by MGIT medium, only 13 were detected by the instrument (P<0.0001). Most tubes yielding M. xenopi exhibited a peculiar pattern of growth characterized by a scant number of round, yellow-pigmented granules instead of the fine, evenly dispersed clumps usually observed for mycobacteria. It is suggested to check all individual tubes discarded by the MGIT 960 system at the end of the incubation period to prevent a significant amount of previously undetected growth from being missed.
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33
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Procop GW. Molecular diagnostics for the detection and characterization of microbial pathogens. Clin Infect Dis 2007; 45 Suppl 2:S99-S111. [PMID: 17683022 DOI: 10.1086/519259] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
New and advanced methods of molecular diagnostics are changing the way we practice clinical microbiology, which affects the practice of medicine. Signal amplification and real-time nucleic acid amplification technologies offer a sensitive and specific result with a more rapid turnaround time than has ever before been possible. Numerous methods of postamplification analysis afford the simultaneous detection and differentiation of numerous microbial pathogens, their mechanisms of resistance, and the construction of disease-specific assays. The technical feasibility of these assays has already been demonstrated. How these new, often more expensive tests will be incorporated into routine practice and the impact they will have on patient care remain to be determined. One of the most attractive uses for such techniques is to achieve a more rapid characterization of the infectious agent so that a narrower-spectrum antimicrobial agent may be used, which should have an impact on resistance patterns.
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Affiliation(s)
- Gary W Procop
- Department of Pathology, Jackson Memorial Hospital and University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
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34
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Ichimura S, Nagano M, Ito N, Shimojima M, Egashira T, Miyamoto C, Ohkusu K, Ezaki T. Evaluation of the invader assay with the BACTEC MGIT 960 system for prompt isolation and identification of mycobacterial species from clinical specimens. J Clin Microbiol 2007; 45:3316-22. [PMID: 17687020 PMCID: PMC2045373 DOI: 10.1128/jcm.02289-06] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rapid and accurate identification of mycobacterial species is essential for patient management. We describe the use of the Invader assay in conjunction with the BACTEC MGIT 960 system that together provide an efficient procedure for clinical use. This assay discriminates single-base differences (e.g., genotyping single-nucleotide polymorphisms) under homogeneous and isothermal conditions and can measure directly on genomic DNA without prior target DNA amplification. To identify a wide variety of mycobacterial species, 20 Invader probes were designed to target the 16S rRNA gene and the 16S-23S rRNA gene internal transcribed spacer 1 (ITS-1) region. To validate the Invader probes, we used 78 ATCC strains, and 607 clinical mycobacterial strains, which were identified by DNA sequencing of the 16S rRNA gene and ITS-1. The Invader assay could accurately identify and differentiate these strains according to target sequences. Moreover, it could detect and identify 116 (95.1%) of 122 positive liquid cultures from the BACTEC MGIT 960 system and did not react to 83 contaminated MGIT cultures. Species identification takes 6.5 h by the Invader assay: 2.0 h for DNA extraction, 0.5 h for handling, and up to 4 h for the Invader reaction. The Invader assay has the speed, ease of use, and accuracy to be an effective procedure for the bacteriological diagnosis of mycobacterial infections.
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Affiliation(s)
- Sadahiro Ichimura
- Department of Microbiology, BML, Inc., 1361-1 Matoba, Kawagoe, Saitama 350-1101, Japan.
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35
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Falconi FQ, Suárez LI, López MDJC, Sancho CG. Comparison of the VersaTREK system and Löwenstein-Jensen medium for the recovery of mycobacteria from clinical specimens. ACTA ACUST UNITED AC 2007; 40:49-53. [PMID: 17852938 DOI: 10.1080/00365540701522967] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Laboratory services for the detection of tuberculosis form an essential component of the DOTS strategy. Our objective was to evaluate the recovery rate and mean time to detection (TTD) of mycobacteria of 2 culture media: the VersaTREK system and the Löwenstein-Jensen medium (LJ). Clinical specimens were processed using the standard N-acetyl-L-cysteine (NALC)-NaOH method, and then inoculated onto VersaTREK system and LJ slants. Of 1510 specimens cultured, a total of 200 mycobacterial isolates (159 Mycobacterium tuberculosis and 41 no M. tuberculosis mycobacteria) were detected. The recovery rates were 84.8% (168/198) for the VersaTREK system and 89.4% (168/188) for LJ (p=0.2); while the contamination rates were 4.2% for the VersaSATREK system and 7.4% for LJ (p<0.001). The TTDs for mycobacteria spp. were 18.2 (+/-11.4) d for the VersaTREK system and 27.9 (+/-10.9) d for LJ (p<0.001). The TTDs for M. tuberculosis were 19.8 (+/-11.2) d for the VersaTREK system and 27.3 (+/-10.2) d for LJ (p<0.001). The difference in TTD between smear-positive and smear-negative specimens for Mycobacterium spp. was 15.9 (+/-10.0) vs 23.0 (+/-12.5) d, and for M. tuberculosis 16.7 (+/-9.5) vs 28.4 (+/-11.1) d for the VersaTREK system. The VersaTREK system significantly reduces the TTDs of mycobacteria detection, which is clinically relevant.
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Affiliation(s)
- Francisco Quiñones Falconi
- Servicio de Microbiología Clínica, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
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36
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Hillemann D, Richter E, Rüsch-Gerdes S. Use of the BACTEC Mycobacteria Growth Indicator Tube 960 automated system for recovery of Mycobacteria from 9,558 extrapulmonary specimens, including urine samples. J Clin Microbiol 2006; 44:4014-7. [PMID: 17005737 PMCID: PMC1698359 DOI: 10.1128/jcm.00829-06] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The BACTEC Mycobacteria Growth Indicator Tube 960 (MGIT 960) system was applied for recovery of mycobacteria from extrapulmonary specimens and compared with solid media (Löwenstein-Jensen and Stonebrink). A total of 9,558 specimens were investigated, comprising 3,074 body fluids, 1,878 tissues, and 2,069 urine samples, from which the recovery of mycobacteria was not yet established for MGIT 960. In total, the MGIT 960 was able to detect 446 (90.3%) of the 494 isolates of Mycobacterium tuberculosis complex (MTBC) and 223 (86.0%) out of the 259 isolates of nontuberculous mycobacteria (NTM). In comparison to this, culture on solid medium revealed 358 (72.6%) MTBC isolates and 164 (66.8%) NTM isolates. While 136 (27.6%) of the MTBC isolates and 95 (19.2%) of the NTM isolates were recovered from the MGIT 960 only, 48 (9.7%) of the MTBC isolates and 36 (13.9%) NTM isolates grew only on solid media. Thus, the overall sensitivities for the recovery of mycobacteria from extrapulmonary specimens with MGIT 960 and solid media were 88.8% and 69.3%, respectively. However, the efficiency of the MGIT 960 system can be maximized with additional culture on solid media.
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Affiliation(s)
- Doris Hillemann
- National Reference Center for Mycobacteria, Forschungszentrum Borstel, Parkallee 18, 23845 Borstel, Germany.
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37
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Soo PC, Horng YT, Hsueh PR, Shen BJ, Wang JY, Tu HH, Wei JR, Hsieh SC, Huang CC, Lai HC. Direct and Simultaneous Identification of Mycobacterium tuberculosis complex (MTBC) and Mycobacterium tuberculosis (MTB) by Rapid Multiplex nested PCR-ICT assay. J Microbiol Methods 2006; 66:440-8. [PMID: 16516314 DOI: 10.1016/j.mimet.2006.01.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Revised: 01/18/2006] [Accepted: 01/23/2006] [Indexed: 11/24/2022]
Abstract
The Mycobacterium tuberculosis (MTB) shows different virulence and host infection range from other members of the M. tuberculosis complex (MTBC). Differential identification of MTB from MTBC is thus important in certain occasions. The currently commercially available molecular assays which use either IS6110 or 16S rDNA fragment as identification targets are mainly designed for identifying MTBC but not for MTB. Comparative genomic DNA analysis has provided valuable information on regions of difference (RD) present in MTB but not in other members of the MTBC. RD9 region is further suggested to be a potential target for differential identification of MTB from MTBC. In this study, using IS6110 and Rv3618 (belong to RD9) as the specific identification targets for MTBC and MTB, respectively, we developed and tested a multiplex nested PCR-ICT (immuno-chromatography test) assay for simultaneously and directly detecting not only MTBC but also MTB from 1500 clinical sputum specimens. The results were compared with traditional culture and biochemical identification results together with patients' clinical assessments. This assay showed a 95.5% sensitivity, 97.9% specificity, 2.1% false positive rate and 4.5% false negative rate towards detection of MTBC, and a 93.0% sensitivity, 99.8% specificity, 0.2% false positive rate and 7.0% false negative rate for detection of MTB. This detection system shows great potential in clinical application.
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Affiliation(s)
- Po-Chi Soo
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, No. 1 Chan-Der Street, Taipei 100, Taiwan, ROC
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38
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LaBombardi VJ, Katariwala R, Pipia G. The identification of mycobacteria from solid media and directly from VersaTREK Myco bottles using the Sherlock Mycobacteria Identification HPLC system. Clin Microbiol Infect 2006; 12:478-81. [PMID: 16643526 DOI: 10.1111/j.1469-0691.2006.01373.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Sherlock Mycobacteria Identification HPLC system correctly identified to the species level 61 (67.8%) of 90 isolates growing on solid media, and 73 (45.3%) of 161 isolates directly from positive VersaTREK Myco bottles. When these data were re-analysed with a revised database, correct identifications increased to 91.1% and 83.2%, respectively. All Mycobacterium tuberculosis isolates were identified correctly, regardless of the inoculum source or database used. The use of the revised database with isolates obtained directly from positive VersaTREK Myco bottles allows the identification of most isolates within clinically relevant time-frames.
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Affiliation(s)
- V J LaBombardi
- Department of Laboratories, St Vincent's Hospital-Manhattan, 153 W. 11th Street, New York, NY 10011, USA.
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39
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Dionne K, Sweeney A, Hedgepeth A, Carroll K, Parrish N. Methods for reducing bacterial contamination in the BacT/Alert mycobacterial culture detection system. J Clin Microbiol 2005; 43:2523-5. [PMID: 15872302 PMCID: PMC1153766 DOI: 10.1128/jcm.43.5.2523-2525.2005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two methods were compared for decreasing bacterial contamination in the BacT/Alert mycobacterial culture detection system. Two concentrations, 0.5 ml (standard amount) and 1.0 ml, of mycobacterial antibiotic supplement were evaluated. Contamination rates were 14% and 6% for the standard and the doubled concentrations, respectively. This difference was statistically significant (P < 0.005).
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Affiliation(s)
- Kim Dionne
- Division of Medical Microbiology, Johns Hopkins University, Meyer B1-193, 600 N. Wolfe Street, Baltimore, MD 21287, USA
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40
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Akselband Y, Cabral C, Shapiro DS, McGrath P. Rapid mycobacteria drug susceptibility testing using Gel Microdrop (GMD) Growth Assay and flow cytometry. J Microbiol Methods 2005; 62:181-97. [PMID: 16009276 DOI: 10.1016/j.mimet.2005.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Revised: 02/11/2005] [Accepted: 02/11/2005] [Indexed: 11/18/2022]
Abstract
Control of multi-drug-resistant tuberculosis has been hampered by the lack of simple, rapid and sensitive methods for assessing bacterial growth and antimicrobial susceptibility. Due to the increasing incidence and high frequency of mutations, it is unlikely that culture methods will disappear in the foreseeable future. Therefore, the need to modernize methods for rapid detection of viable clinical isolates, at a minimum as a gold standard, will persist. Previously, we confirmed the feasibility of using the Gel Microdrop (GMD) Growth Assay for identifying sub-populations of resistant Mycobacteria by testing different laboratory strains. Briefly, this assay format relies on encapsulating single bacterium in agarose microspheres and identifying clonogenic growth using flow cytometry and fluorescent staining. In this study, we modified the GMD Growth Assay to make it suitable for clinical applications. We demonstrated the effectiveness and safety of this novel approach for detecting drug susceptibility in clinically relevant laboratory strains as well as clinical isolates of Mycobacterium tuberculosis. Correlation between results using the GMD Growth Assay format and results using two well characterized methods (Broth Microdilution MIC and BACTEC 460TB) was 87.5% and 90%, respectively. However, due to the inherent sensitivity of flow cytometry and the ability to detect small (<1%) sub-populations of resistant mycobacteria, the GMD Growth Assay identified more cases of drug resistance. Using 4 clinically relevant mycobacterial strains, we assessed susceptibility to primary anti-tuberculosis drugs using both the Broth Microdilution MIC method and the GMD Growth Assay. We performed 24 tests on isoniazid-resistant BCG, Mycobacterium tuberculosis H37Ra and Mycobacterium avium strains. The Broth Microdilution MIC method identified 7 cases (29.1%) of resistance to INH and EMB compared to the GMD Growth Assay which identified resistance in 10 cases (41.6%); in 3 cases (12.5%), resistance to INH and EMB was detected only with the GMD Growth Assay. In addition, using 20 Mycobacterium tuberculosis clinical isolates, we compared results using BACTEC 460TB method performed by collaborators and the GMD Growth Assay. Eight of 20 (40%) clinical isolates, which were not identified as drug-resistant using the conventional BACTEC 460TB method, were resistant to 1, 2, or 3 different concentrations of drugs using the GMD Growth Assay (13 cases of 140 experiments). In one case (isolate 1879), resistance to 10.0 microg/ml of STR detected using BACTEC 460TB method was not confirmed by the GMD Growth Assay. Thus, the overall agreement between these methods was 90% (14 discrepant results of 140 experiments). These data demonstrate that the GMD Growth Assay is an accurate and sensitive method for rapid susceptibility testing of Mycobacterium tuberculosis for use in clinical reference laboratory settings.
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Affiliation(s)
- Y Akselband
- One Cell Systems, Inc., Suite 200, 100 Inman Street, Cambridge, MA 02139, United States.
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41
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Thrupp L, Bradley S, Smith P, Simor A, Gantz N, Crossley K, Loeb M, Strausbaugh L, Nicolle L. Tuberculosis prevention and control in long-term-care facilities for older adults. Infect Control Hosp Epidemiol 2005; 25:1097-108. [PMID: 15636299 DOI: 10.1086/502350] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the United States, older adults comprise 22% of cases of tuberculous disease but only 12% of the population. Most cases of tuberculosis (TB) occur in community dwellers, but attack rates are highest among frail residents of long-term-care facilities. The detection and treatment of latent TB infection and TB disease can pose special challenges in older adults. Rapid recognition of possible disease, diagnosis, and implementation of airborne precautions are essential to prevent spread. It is the intent of this evidence-based guideline to assist healthcare providers in the prevention and control of TB, specifically in skilled nursing facilities for the elderly.
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Affiliation(s)
- Lauri Thrupp
- Infection Control Department, University of California Irvine Medical Center, Orange, California, USA
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42
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Miller DR, Deml SM, Guruswamy AP, Ostgaard LK, Schneider PS, Hata DJ, Roberts GD. Rapid recovery and identification of Mycobacterium tuberculosis within 48 hours of receipt of a clinical specimen — efficient use of rapid methods. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.clinmicnews.2004.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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43
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Cruciani M, Scarparo C, Malena M, Bosco O, Serpelloni G, Mengoli C. Meta-analysis of BACTEC MGIT 960 and BACTEC 460 TB, with or without solid media, for detection of mycobacteria. J Clin Microbiol 2004; 42:2321-5. [PMID: 15131224 PMCID: PMC404614 DOI: 10.1128/jcm.42.5.2321-2325.2004] [Citation(s) in RCA: 184] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In a meta-analysis of 10 studies, the BACTEC 960/MGIT and BACTEC 460 systems showed a sensitivity and specificity in detecting mycobacteria (1,381 strains from 14,745 clinical specimens) of 81.5 and 99.6% and 85.8 and 99.9%, respectively. Combined with solid media, the sensitivity of the two systems increased to 87.7 and 89.7%, respectively.
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Affiliation(s)
- M Cruciani
- HIV Outpatient Clinic, Center of Preventive Medicine, Verona, Italy.
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44
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Kontos F, Petinaki E, Nicolaou S, Gitti Z, Anagnostou S, Maniati M, Costopoulos C, Tselentis I, Maniatis AN. Multicenter evaluation of the fully automated bactec MGIT 960 system and three molecular methods for the isolation and the identification of mycobacteria from clinical specimens. Diagn Microbiol Infect Dis 2003; 46:299-301. [PMID: 12944024 DOI: 10.1016/s0732-8893(03)00078-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A combination of Bactec MGIT 960 system, a PCR-based assay and a PCR-Restriction Analysis procedure (PRA) was assessed for the detection and identification of mycobacteria from clinical samples. The MGIT recovered 243 from 266 mycobacterial isolates. The PCR-based assay correctly identified all (234) Mycobacterium tuberculosis isolates, while 35 nontuberculous mycobacterial isolates were identified by PRA.
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Affiliation(s)
- F Kontos
- Department of Microbiology, Medical School, University Hospital of Larissa, Papakyriazi 22, Larissa, Greece
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45
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Somoskovi A, Song Q, Mester J, Tanner C, Hale YM, Parsons LM, Salfinger M. Use of molecular methods to identify the Mycobacterium tuberculosis complex (MTBC) and other mycobacterial species and to detect rifampin resistance in MTBC isolates following growth detection with the BACTEC MGIT 960 system. J Clin Microbiol 2003; 41:2822-6. [PMID: 12843007 PMCID: PMC165292 DOI: 10.1128/jcm.41.7.2822-2826.2003] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A prospective study was organized by using a total of 1,585 consecutive clinical specimens to determine whether biomass obtained from positive growth in the MGIT 960 system could be used directly in AccuProbe DNA hybridization tests, the PCR-based Inno-LiPA Rif.TB (LiPA) assay, and a PCR-based DNA sequencing of the rpoB gene for the rapid identification of the Mycobacterium tuberculosis complex (MTBC) and other mycobacterial species and for the determination of rifampin (RIF) resistance in MTBC strains. The results were compared to routine culture, identification, and susceptibility testing techniques performed on the same samples. The study results revealed that the DNA AccuProbe assay (on the day of growth positivity) readily identified 95.7%, the LiPA assay readily identified 98.6%, and rpoB sequencing readily identified 97.1% of the 70 MTBC isolates from mycobacterial growth indicator tubes (MGIT). In addition, application of the LiPA for the identification and RIF susceptibility testing of the MTBC in growth-positive MGIT resulted in a turnaround time of less than 2 weeks after specimen receipt. Although DNA sequencing of rpoB required a slightly longer (16 days) turnaround time, this method was capable of identifying several species of nontuberculous mycobacteria in addition to identifying MTBC and determining RIF susceptibility or resistance. The molecular methods were also found to rapidly identify RIF-susceptible and -resistant MTBC in two of the three mixed mycobacterial cultures weeks earlier than conventional methods. In conclusion, the biomass obtained in MGIT at the time of growth positivity in the 960 system is sufficient for use in all three molecular tests, and this approach can reduce the turnaround time for reporting results.
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Affiliation(s)
- Akos Somoskovi
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
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46
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Lebrun L, Gönüllü N, Boutros N, Davoust A, Guibert M, Ingrand D, Ghnassia JC, Vincent V, Doucet-Populaire F. Use of INNO-LIPA assay for rapid identification of mycobacteria. Diagn Microbiol Infect Dis 2003; 46:151-3. [PMID: 12812720 DOI: 10.1016/s0732-8893(03)00042-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using 106 clinical isolates of mycobacteria, we showed that INNO-LIPA Mycobacteria assay is an excellent tool to rapidly identify the most frequently isolated nontuberculous mycobacteria, in one procedure. It may be used as an additional technique to AccuProbe assay, which remains the fastest and the cheapest tool for a rapid and accurate identification of the M. tuberculosis complex.
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Affiliation(s)
- Léa Lebrun
- Microbiology Laboratories, AP-HP, Hospital Antoine Béclère, Clamart, France.
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47
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Bardarov S, Dou H, Eisenach K, Banaiee N, Ya SU, Chan J, Jacobs WR, Riska PF. Detection and drug-susceptibility testing of M. tuberculosis from sputum samples using luciferase reporter phage: comparison with the Mycobacteria Growth Indicator Tube (MGIT) system. Diagn Microbiol Infect Dis 2003; 45:53-61. [PMID: 12573551 DOI: 10.1016/s0732-8893(02)00478-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Rapid diagnosis of drug-resistant M.tuberculosis (Mtb) is desirable worldwide. We (i) describe a new luciferase reporter phage (LRP), phAE142 for this purpose; (ii) compare it to the automated MGIT 960 for time-to-detection of Mtb in clinical specimens; and (iii) evaluate its use for species confirmation and antibiotic susceptibility testing(AST) of Mtb. Twenty sputum samples were inoculated for testing by LRP, or by MGIT 960. After "positives" were identified by either method, the LRP was used for confirmation of Mtb complex (TBC) and for AST. The LRP method proved comparably efficient to MGIT 960 at detecting Mtb. Using an antibiotic uniquely inhibiting TBC with LRP provided species assignment, concurrently with AST, in a median of 3 days, with a sensitivity of 97%. Overall agreement in susceptibility results was 96%. Reliable susceptibility results and identification of TBC can be completed in a median of 12 days (range 8 to 16d) with LRP applied to sputum samples.
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Han XY, Pham AS, Tarrand JJ, Sood PK, Luthra R. Rapid and accurate identification of mycobacteria by sequencing hypervariable regions of the 16S ribosomal RNA gene. Am J Clin Pathol 2002; 118:796-801. [PMID: 12428802 DOI: 10.1309/hn44-xqym-jmaq-2edl] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
We developed a method to identify mycobacteria by sequencing hypervariable regions of the polymerase chain reaction-amplified 16S ribosomal RNA gene. This method is nearly specific for mycobacteria and uses positive culture from liquid or solid medium without the needfor lengthy subculture. It shortens identification time to 3 days, which is much faster than the conventional biochemical method (mean, 8 weeks). It applies to all mycobacteria (approximately 100 species), unlike current nucleic acid hybridization methods, which probe only 4 species. The identifications are the same or are species specific for the well-characterized mycobacteria (59/68 [87%]) or more accurate for recently proposed species (9/68 [13%]). The method requires a single sequencing reaction, which is efficient and cost-effective. Therefore, this method is clinically and academically useful.
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Affiliation(s)
- Xiang Y Han
- Division of Pathology and Laboratory Medicine, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA
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Scarparo C, Piccoli P, Rigon A, Ruggiero G, Ricordi P, Piersimoni C. Evaluation of the BACTEC MGIT 960 in comparison with BACTEC 460 TB for detection and recovery of mycobacteria from clinical specimens. Diagn Microbiol Infect Dis 2002; 44:157-61. [PMID: 12458122 DOI: 10.1016/s0732-8893(02)00437-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The BACTEC MGIT system (M960), a fully automated, non radiometric instrument, designed for rapid detection of acid fast bacilli (AFB) from clinical specimens, was compared with the radiometric BACTEC 460 system (B460) and Löwenstein-Jensen (L-J) solid medium. A total of 1,093 respiratory and extrapulmonary specimens were decontaminated by the NALC-NaOH standard method, and randomly inoculated into the media. A total of 122 mycobacteria were recovered, including 47 Mycobacterium tuberculosis complex (MTB) isolates and 75 nontuberculous mycobacteria (NTM) isolates. Overall recovery rates were 59% for M960 system (p < 0.0001), 58.2% for L-J. medium (p < 0.0001) and 82% for Bactec 460 system, whereas rates for MTB alone were 91.5, 76.6 (p = 0.007), and 95.7%, respectively. The combination of M960 or B460 systems with L-J medium showed the same recovery rates for MTB strains (97.9%), whereas NTM rates were 68% (p < 0.0001) and 93.3%, respectively. Mean time to detection of smear-positive MTB, smear-negative MTB, and NTM were 12.2, 13.4, and 23.3 days, respectively, with the M960, 11.7, 21.3, and 24.8 days with the B460 and 20.4, 28.7, and 28.4 days with L-J medium. The M960 system showed a contamination rate of 9.8%, while B460 and L-J medium showed contamination rates of 4.3 and 3.8% respectively. In conclusion, the M960 system appeared to be accurate and rapid for the recovery of MTB, but reduced recovery of NTM and a high number of contaminated cultures deserve further study in order to assess if this system can represent a valuable alternative to the radiometric system.
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Affiliation(s)
- Claudio Scarparo
- Regional Mycobacteria Reference Center, Laboratory of Clinical Microbiology and Virology, San Bortolo Hospital, Vicenza, Italy.
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Romano L, Sanguinetti M, Posteraro B, Ardito F, Gesu G, Schito AM, Fadda G. Early detection of negative BACTEC MGIT 960 cultures by PCR-reverse cross-blot hybridization assay. J Clin Microbiol 2002; 40:3499-501. [PMID: 12202603 PMCID: PMC130771 DOI: 10.1128/jcm.40.9.3499-3501.2002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We evaluated the efficacy of a PCR-reverse cross-blot hybridization assay, a test which permits identification of mycobacteria by means of species-specific probes and a Mycobacterium-specific probe, for early detection of negative BACTEC MGIT 960 mycobacterial cultures. Aliquots of 549 cultures were collected 7 days after the culture media were inoculated with various clinical specimens and tested with the molecular assay. PCR results were compared to those obtained at the end times with the BACTEC MGIT 960 system. Of the 549 specimens analyzed, 484 were found to be negative and 64 were found positive by both methods; one specimen, found to be positive by the BACTEC MGIT 960 system, was identified as negative by the molecular assay. In view of its high negative predictive value (99.8%), the PCR-reverse cross-blot hybridization assay appears to be a valid tool for early detection of negative BACTEC MGIT 960 cultures.
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Affiliation(s)
- Lucio Romano
- Istituto di Microbiologia, Università Cattolica del Sacro Cuore, Rome, Italy
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