scholarly journals Current Perceptionson Advanced Molecular Diagnostics for Drug-Resistant Mycobacterium tuberculosis

2021 ◽  
Vol 14 (3) ◽  
pp. 1249-1257
Author(s):  
Pushparaju Ramasamy ◽  
Vignesh Sounderrajan ◽  
Kevin Kumar Vijayakumar ◽  
Shakila Harshavardhan
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Point Of Care ◽  
Health Concern ◽  
Drug Resistant ◽  
X Rays ◽  
Resistance Mutations ◽  
Resistant Tuberculosis ◽  
Pet Ct ◽  
Significant Public Health ◽  
Essential Resource

Globally, rising drug-resistant tuberculosis is a significant public health concern. Prompt diagnosis of tuberculosis and detection of drug-resistant TB within a clinically appropriate timeframe is important for the effective management of the disease. Imaging approaches Chest X-rays, CT, MRI, nuclear medicine technique as PET/CT are non-specific, plays an important role in the diagnosis and assessment of TB, but PET/CT sometimes results in false-positive or negative due to benign lesions.Currently using the point of care molecular modalities, Gene Xpert MTB/RIF and line probe assays focused only on resistance-conferring mutations in specific target hotspot regions, but did not identify novel mutations, outside mutations and they may miss some locally prevalent rifampicin-conferring mutations, and not provided a large number of antibiotics/antibiotic groups that are used for DRTB treatment.Recently revolutionized high throughput next generation sequencing (NGS) technologies are offering new prospects for molecular diagnosis, for example, infectious disease pathogens like tuberculosis, influenza, and most recently SARS-CoV-2. NGS is an essential resource for the tuberculosis communityeither target, WGS, or NGS; a rapid method that offers a complete spectrum of Mycobacterium tuberculosis resistance mutations, strain typing for transmission surveillance, unlike traditional molecular or phenotypic DST. It shall be helpful for early regimen design and TB management before mutations emerge and therefore, we believe that the worldwide TB infection will be eliminated by the use of NGS.

scholarly journals Identifying drug-resistant tuberculosis from chest X-ray images using a simple convolutional neural network

2021 ◽  
Vol 2071 (1) ◽  
pp. 012001
Author(s):  
J Ureta ◽  
A Shrestha
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Binary Classification ◽  
Health Concern ◽  
Drug Resistant ◽  
X Rays ◽  
Drug Resistant Tuberculosis ◽  
X Ray ◽  
Resistant Tuberculosis ◽  
Chest X Ray

Abstract Tuberculosis(TB) is one of the top 10 causes of death worldwide, and drug-resistant TB is a major public health concern especially in resource-constrained countries. In such countries, molecular diagnosis of drug-resistant TB remains a challenge; and imaging tools such as X-rays, which are cheaply and widely available, can be a valuable supplemental resource for early detection and screening. This study uses a specialized convolutional neural network to perform binary classification of chest X-ray images to classify drug-resistant and drug-sensitive TB. The models were trained and validated using the TBPortals dataset which contains 2,973 labeled X-ray images from TB patients. The classifiers were able to identify the presence or absence of drug-resistant Tuberculosis with an AUROC between 0.66–0.67, which is an improvement over previous attempts using deep learning networks.

scholarly journals Detection of Isoniazid-, Fluoroquinolone-, Amikacin-, and Kanamycin-Resistant Tuberculosis in an Automated, Multiplexed 10-Color Assay Suitable for Point-of-Care Use

2016 ◽  
Vol 55 (1) ◽  
pp. 183-198 ◽  
Author(s):  
Soumitesh Chakravorty ◽  
Sandy S. Roh ◽  
Jennifer Glass ◽  
Laura E. Smith ◽  
Ann Marie Simmons ◽  
...  
Keyword(s):  
Point Of Care ◽  
Stokes Shift ◽  
Drug Resistant ◽  
Wild Type ◽  
Resistance Mutations ◽  
Content Type ◽  
Automated Assay ◽  
Resistant Tuberculosis ◽  
Three Phase ◽  
Selection Of

ABSTRACTExtensively drug-resistant (XDR) tuberculosis (TB) cannot be easily or quickly diagnosed. We developed a rapid, automated assay for the detection of XDR-TB plus resistance to the drug isoniazid (INH) for point-of-care use. Using a simple filter-based cartridge with an integrated sample processing function, the assay identified a wide selection of wild-type and mutant sequences associated with XDR-TB directly from sputum. Four new large-Stokes-shift fluorophores were developed. When these four Stokes-shift fluorophores were combined with six conventional fluorophores, 10-color probe detection in a single PCR tube was enabled. A new three-phase, double-nested PCR approach allowed robust melting temperature analysis with enhanced limits of detection (LODs). Finally, newly designed sloppy molecular beacons identified many different mutations using a small number of probes. The assay correctly distinguished wild-type sequences from 32 commonly occurring mutant sequences tested ingyrA,gyrB,katG, andrrsgenes and the promoters ofinhAandeisgenes responsible for resistance to INH, the fluoroquinolone (FQ) drugs, amikacin (AMK), and kanamycin (KAN). The LOD was 300 CFU ofMycobacterium tuberculosisin 1 ml sputum. The rate of detection of heteroresistance by the assay was equivalent to that by Sanger sequencing. In a blind study of 24 clinical sputum samples, resistance mutations were detected in all targets with 100% sensitivity, with the specificity being 93.7 to 100%. Compared to the results of phenotypic susceptibility testing, the sensitivity of the assay was 75% for FQs and 100% each for INH, AMK, and KAN and the specificity was 100% for INH and FQ and 94% for AMK and KAN. Our approach could enable testing for XDR-TB in point-of-care settings, potentially identifying highly drug-resistant TB more quickly and simply than currently available methods.

scholarly journals Whole genome analysis of extensively drug resistant Mycobacterium tuberculosis strains in Peru

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David Santos-Lazaro ◽  
Ronnie G. Gavilan ◽  
Lely Solari ◽  
Aiko N. Vigo ◽  
Zully M. Puyen
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Multidrug Resistant ◽  
Annual Number ◽  
Whole Genome ◽  
Drug Resistant ◽  
Resistance Mutations ◽  
Whole Genome Analysis ◽  
Evolutionary Patterns ◽  
Resistant Tuberculosis ◽  
Extensively Drug Resistant

AbstractPeru has the highest burden of multidrug-resistant tuberculosis in the Americas region. Since 1999, the annual number of extensively drug-resistant tuberculosis (XDR-TB) Peruvian cases has been increasing, becoming a public health challenge. The objective of this study was to perform genomic characterization of Mycobacterium tuberculosis strains obtained from Peruvian patients with XDR-TB diagnosed from 2011 to 2015 in Peru. Whole genome sequencing (WGS) was performed on 68 XDR-TB strains from different regions of Peru. 58 (85.3%) strains came from the most populated districts of Lima and Callao. Concerning the lineages, 62 (91.2%) strains belonged to the Euro-American Lineage, while the remaining 6 (8.8%) strains belonged to the East-Asian Lineage. Most strains (90%) had high-confidence resistance mutations according to pre-established WHO-confident grading system. Discordant results between microbiological and molecular methodologies were caused by mutations outside the hotspot regions analysed by commercial molecular assays (rpoB I491F and inhA S94A). Cluster analysis using a cut-off ≤ 10 SNPs revealed that only 23 (34%) strains evidenced recent transmission links. This study highlights the relevance and utility of WGS as a high-resolution approach to predict drug resistance, analyse transmission of strains between groups, and determine evolutionary patterns of circulating XDR-TB strains in the country.

scholarly journals Use of fluorescein diacetate (FDA) staining to detect viable Mycobacterium tuberculosis

2012 ◽  
Vol 11 (4) ◽  
pp. 322-330 ◽  
Author(s):  
Shamima Islam ◽  
Farjana Rahman ◽  
Saurab Kisore Munshi ◽  
Jewel Ahmed ◽  
S M Mostafa Kamal ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Treatment Failure ◽  
Medical Science ◽  
Multidrug Resistant ◽  
Fluorescein Diacetate ◽  
Drug Resistant ◽  
Drug Resistant Tuberculosis ◽  
Resistant Tuberculosis ◽  
Multidrug Resistant Tuberculosis ◽  
Auramine O

Objective: Drug resistant tuberculosis has long been a common problem prevailing in developing countries including Bangladesh. Present study focused on the rapid identification of live Mycobacterium tuberculosis among treatment failure cases.Materials and Methods: Sputum samples from a total of 100 category-I and category-II treatment failure cases, assumed as multidrug resistant tuberculosis, were studied through fluorescein diacetate (FDA) staining under light emitting diode (LED) fluorescence microscope. Considering culture method as gold standard, we also compared the results of FDA staining with that of auramine O staining.Results: A total of 85% acid-fast bacilli were detected by FDA staining, 82% by auramine O staining and a total of 85% isolates were detected in Lowenstein-Jensen (LJ) culture. The sensitivity of FDA staining (96.47%) was estimated to be slightly higher than that of auramine O staining (91.76%). Moreover,76.47% cases were detected as multidrug resistant tuberculosis (MDR-TB). Conclusion: Taken together, FDA staining method has been proposed to be appropriate for the rapid diagnosis of drug resistant tuberculosis. DOI: http://dx.doi.org/10.3329/bjms.v11i4.12605 Bangladesh Journal of Medical Science Vol. 11 No. 04 Oct’12

scholarly journals Tuberculose Multirresistente por Estirpes da Família Beijing, em Doentes de Lisboa, Portugal: Estudo Preliminar

2017 ◽  
Vol 30 (3) ◽  
pp. 175 ◽  
Author(s):  
Fernando Maltez ◽  
Teresa Martins ◽  
Diana Póvoas ◽  
João Cabo ◽  
Helena Peres ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Past History ◽  
Multidrug Resistant ◽  
Resistance Pattern ◽  
Drug Resistant ◽  
Beijing Family ◽  
Resistant Tuberculosis ◽  
Extensively Drug Resistant ◽  
Number Of Patients ◽  
Drug Resistant Strains

Introduction: Beijing family strains of Mycobacterium tuberculosis are associated with multidrug-resistance. Although strains of the Lisboa family are the most common among multidrug-resistant and extensively drug-resistant patients in the region, several studies have reported the presence of the Beijing family. However, the features of patients from whom they were isolated, are not yet known.Material and Methods: Retrospective study involving 104 multidrug-resistant and extensively drug-resistant strains of Mycobacterium tuberculosis, from the same number of patients, isolated and genotyped between 1993 and 2015 in Lisbon. We assessed the prevalence of strains of both families and the epidemiologic and clinical features of those infected with Beijing family strains.Results: Seventy-four strains (71.2%) belonged to the Lisboa family, 25 (24.0%) showed a unique genotypic pattern and five (4.8%) belonged to the Beijing family, the latter identified after 2009. Those infected with Beijing family strains were angolan (n = 1), ukrainian (n = 2) and portuguese (n = 2), mainly young-aged and, four of five immunocompetent and with no past history of tuberculosis. All had multidrug-resistant tuberculosis. We did not find any distinctive clinical or radiological features, neither a predominant resistance pattern. Cure rate was high (four patients).Discussion: Although the number of infected patients with Beijing strains was small, it suggests an important proportion of primary tuberculosis, a potential for transmission in the community but also a better clinical outcome when compared to other reported strains, such as W-Beijing and Lisboa.Conclusion: Although Lisboa family strains account for most of the multidrug and extensively drug-resistant tuberculosis cases in Lisbon area, Beijing strains are transmitted in the city and might change the local characteristics of the epidemics.

scholarly journals Bazedoxifene Suppresses Intracellular Mycobacterium tuberculosis Growth by Enhancing Autophagy

mSphere ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Qi Ouyang ◽  
Kehong Zhang ◽  
Dachuan Lin ◽  
Carl G. Feng ◽  
Yi Cai ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Antimycobacterial Activity ◽  
Multidrug Resistant ◽  
Drug Resistant ◽  
New Host ◽  
Drug Resistant Tuberculosis ◽  
Content Type ◽  
Receptor Modulator ◽  
Resistant Tuberculosis ◽  
Negative Side Effects

ABSTRACT Tuberculosis (TB) is still the leading killer caused by Mycobacterium tuberculosis infection. There is a clear need for new treatment strategy against TB. It has been reported that tamoxifen, known as a selective estrogen receptor modulator (SERM), exhibits antimycobacterial activity and inhibits M. tuberculosis growth in macrophages. However, it remains unknown whether such antimicrobial activity is a general property of all SERMs and how it works. In this study, we identified that bazedoxifene (BZA), a newer SERM, inhibits intracellular M. tuberculosis growth in macrophages. BZA treatment increases autophagosome formation and LC3B-II protein expression in M. tuberculosis-infected macrophages. We further demonstrated that the enhancement of autophagy by BZA is dependent on increased reactive oxygen species (ROS) production and associated with phosphorylation of Akt/mTOR signaling. In summary, our data reveal a previously unappreciated antimicrobial function of BZA and suggest that future investigation focusing on the mechanism of action of SERMs in macrophages may lead to new host-directed therapies against TB. IMPORTANCE Since current strategies for the treatment of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) have low efficacy and highly negative side effects, research on new treatments including novel drugs is essential for curing drug-resistant tuberculosis. Host-directed therapy (HDT) has become a promising idea to modulate host cell responses to enhance protective immunity against pathogens. Bazedoxifene (BZA), which belongs to a new generation of SERMs, shows the ability to inhibit the growth of M. tuberculosis in macrophages and is associated with autophagy. Our findings reveal a previously unrecognized antibacterial function of BZA. We propose that the mechanism of SERMs action in macrophages may provide a new potential measure for host-directed therapies against TB.

scholarly journals GeneXpert MTB/RIF Assay for Rapid Identification of Mycobacterium Tuberculosis and Rifampicin Resistance Directly from Sputum Sample

2017 ◽  
Vol 7 (2) ◽  
pp. 86-89 ◽  
Author(s):  
Nourjahan Laskar ◽  
Md Akram Hossain ◽  
Jannatul Fardows ◽  
Mominur Rahman
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Sputum Sample ◽  
Rapid Identification ◽  
Rapid Diagnosis ◽  
World Health ◽  
Multi Drug Resistance ◽  
Drug Resistant ◽  
Resistant Tuberculosis ◽  
The World ◽  
Health Organization

Background: The World Health Organization has endorsed the use of molecular methods for the detection of tuberculosis (TB) and drug resistant TB as a rapid method. In Bangladesh, the Xpert MTB/RIF assay has been implemented into reference laboratories for diagnosis of TB and also MDR TB.Objective: Drug resistant tuberculosis has long been a common problem prevailing in our country. The present study focused on the rapid identification of Mycobacterium tuberculosis as well as drug resistance.Materials and Methods: Sputum samples from a total of 107 cases, assumed as multi-drug resistance tuberculosis, were studied through GeneXpert assay.Results: Out of 107 cases, 91 (85.05%) were detected having M. tuberculosis ? 64 (59.81%) were rifampicin sensitive and 27 (25.23%) were rifampicin resistant. The sensitivity and specificity of the GeneXpert are 87.64% and 75% respectively.Conclusion: GeneXpert assay can be considered for the rapid diagnosis of drug resistant tuberculosis.J Enam Med Col 2017; 7(2): 86-89

scholarly journals Genome Sequencing of Polydrug-, Multidrug-, and Extensively Drug-Resistant Mycobacterium tuberculosis Strains from South India

2019 ◽  
Vol 8 (12) ◽  
Author(s):  
Sivakumar Shanmugam ◽  
Narender Kumar ◽  
Dina Nair ◽  
Mohan Natrajan ◽  
Srikanth Prasad Tripathy ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
South India ◽  
Sequence Data ◽  
Whole Genome ◽  
Drug Resistant ◽  
Resistance Mutations ◽  
Content Type ◽  
Extensively Drug Resistant

The genomes of 16 clinical Mycobacterium tuberculosis isolates were subjected to whole-genome sequencing to identify mutations related to resistance to one or more anti-Mycobacterium drugs. The sequence data will help in understanding the genomic characteristics of M. tuberculosis isolates and their resistance mutations prevalent in South India.

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