Utility of pleural fluid-derived extracellular vesicles as a source of Mycobacterium tuberculosis antigens MPT51 and MPT64 for pleural TB diagnosis: a proof-of-concept study.

Extracellular vesicles (EVs) have recently emerged as a source of microbe-specific biomarkers for disease diagnosis. In the present study, we evaluated the utility of pleural fluid-derived extracellular vesicles (pEVs) as a source of Mycobacterium tuberculosis (M. tb.

Identification of Nontuberculous Mycobacterium Species by Polymerase Chain Reaction - Restriction Enzyme Analysis (PCR-REA) of rpoB gene in Clinical Isolates.

Background: Nontuberculous mycobacteria (NTM) infections are an emerging global health concern with increasing incidence. Conventional identification methods for NTM species in clinical settings are prone to errors. This study evaluates a newer method, polymerase chain reaction-restriction enzyme analysis (PCR-REA) of the rpoB gene, for NTM species identification.

Operational feasibility and multi-centric evaluation of 'TB sputum microscopy kit' for the direct detection of in field settings.

Background: India relies primarily on direct smear microscopy for tuberculosis (TB) diagnosis. However, the low sensitivity of smear microscopy emphasizes the need to improve its performance. We recently described the development of 'TB' kit which showed improved performance over direct smear microscopy at National Reference Laboratories (NRLs) in India.

Safety and Efficacy of 25 mg/kg and 35 mg/kg vs 10 mg/kg Rifampicin in Pulmonary TB: A Phase IIb Randomized Controlled Trial.

Background: Globally, no trial data are available on head-to-head comparison between 10 mg/kg and 25/35 mg/kg rifampicin in treating pulmonary tuberculosis during study initiation.

Methods: A multicentric, phase IIb randomized trial recruited 333 new culture-positive, drug-sensitive adult patients with pulmonary tuberculosis to compare safety and efficacy of high-dose rifampicin (R25/R35), against conventional dose (R10) given daily for 8 weeks followed by standard doses for 16 weeks. Main outcomes were treatment-emergent grade 3/4 adverse events (AEs) and time-to-culture conversion in liquid media, assessed by division of AIDS system for grading the severity of adverse events division of AIDS criteria and Kaplan-Meier methods.

Direct Detection of Fluoroquinolone Resistance in Sputum Samples from Tuberculosis Patients by High Resolution Melt Curve Analysis.

Multidrug-resistant tuberculosis (MDR-TB) requires treatment with fluoroquinolone (FLQ) drugs, however, the excessive use of FLQ has led to the rise of extensively drug-resistant TB. In 2019, ~ 20% of total MDR-TB cases were estimated to be resistant to FLQ drugs. In the present study, we developed and evaluated the utility of high-resolution melt curve analysis (HRM) for the rapid detection of FLQ-resistant Mycobacterium tuberculosis for the first time directly from sputum samples.

Drug Resistance in Osteoarticular Tuberculosis: A Study From an Endemic Zone.

The present study was undertaken to determine the incidence of drug resistance against anti-tubercular drugs among patients from an endemic zone.  Methodology: Forty consecutive clinico-radiologically diagnosed patients of osteoarticular tuberculosis (29: spine, 11: extraspinal) were enrolled. Pus from needle aspiration was taken in 31 cases, tissue following spinal decompression in seven, synovial in one, and sinus edge biopsy in one.

Recovery rates of mycobacterium from suspected extra-pulmonary tuberculosis patients using liquid culture at a tertiary referral centre of India.

Tuberculosis still remains a serious public health problem in developing countries. Rapid isolation of mycobacteria is critical for accurate diagnosis and management of tuberculosis. In the present study BACTEC MGIT 960 system was evaluated against Lowenstein Jensen (LJ) medium for isolation of mycobacteria from different extra-pulmonary specimens (N = 371).

Diagnostic utility of GenoType MTBDR assay for the detection of moxifloxacin-resistant , as compared to phenotypic method and whole-genome sequencing.

Background: Recently, moxifloxacin (MFX)-resistant results of Mycobacterium tuberculosis (Mtb) obtained by GenoType MTBDRsl (second-line line probe assay [SL-LPA]) have been stratified to determine their resistance level; however, its accuracy has not been well studied. Therefore, the study aimed to evaluate the diagnostic accuracy of SL-LPA, with phenotypic drug susceptibility testing (pDST) and whole-genome sequencing (WGS) for the detection of MFX-resistant Mtb and their resistance level.

Methods: A total of 111 sputum samples were subjected to SL-LPA according to the diagnostic algorithm of the National Tuberculosis Elimination Program.

Direct Molecular Detection of Drug-Resistant Tuberculosis from Transported Bio-Safe Dried Sputum on Filter-Paper.

In 2019, amongst half a million new rifampicin-resistant tuberculosis (TB) cases, 78% were multi drug-resistant TB (MDR-TB). Access to rapid and Universal-Drug susceptibility testing (DST) to patients in remote areas is a major challenge to combat drug-resistant TB. To overcome this challenge, we had recently reported the development of 'TB Concentration & Transport kit' for bio-safe ambient temperature transport of dried sputum on filter-paper (Trans-Filter).

Correlation of mutations and ethionamide susceptibility: Experience from national reference center for tuberculosis.

Background: Detection of ethionamide (ETH) resistance is crucial as it is part of antitubercular regime. It is crucial to examine the role of inhA gene mutations as a surrogate marker for the detection of ETH resistance, in the Indian context. The present retrospective study was designed with this objective.

Carbapenem-resistant bacteria on hand-held and hands-free electronic devices of healthcare workers and non-healthcare workers in Delhi, India.

Background: Monitoring sensitivity profiles of circulating hospital strains is a key activity of a hospital infection control policy. The hospital environment and equipment may be reservoirs for carbapenem-resistant bacteria. Mobile phones have been shown to be a potential source for the transmission of bacteria in the healthcare environment.

Detection of isoniazid, fluoroquinolone, ethionamide, amikacin, kanamycin, and capreomycin resistance by the Xpert MTB/XDR assay: a cross-sectional multicentre diagnostic accuracy study.

Background: The WHO End TB Strategy requires drug susceptibility testing and treatment of all people with tuberculosis, but second-line diagnostic testing with line-probe assays needs to be done in experienced laboratories with advanced infrastructure. Fewer than half of people with drug-resistant tuberculosis receive appropriate treatment. We assessed the diagnostic accuracy of the rapid Xpert MTB/XDR automated molecular assay (Cepheid, Sunnyvale, CA, USA) to overcome these limitations.

Compatibility of a novel filter paper-based bio-safe sputum transport kit with line probe assay for diagnosing drug-resistant tuberculosis: a single-site evaluation study.

Background: Near-patient access to appropriate tests is a major obstacle for the efficient diagnosis of tuberculosis (TB) and associated drug resistance.

Methods: We recently developed the "TB Concentration & Transport" kit for bio-safe, ambient-temperature transportation of dried sputum on -Filter, and the "TB DNA Extraction" kit for DNA extraction from -Filter for determining drug resistance by DNA sequencing. In the present study, we evaluated the compatibility of Kit-extracted DNA with Hain's line probe assays (LPAs), which are endorsed by National TB programmes for the detection of drug resistance in sputum collected from presumptive multidrug-resistant TB patients (=207).

Detection of New Delhi metallo-beta-lactamase enzyme gene associated with the Int-1 gene in Gram-negative bacteria collected from the effluent treatment plant of a tuberculosis care hospital in Delhi, India.

Background: Organisms possessing the gene (responsible for carbapenem resistance) with a class-1 integron can acquire many other antibiotic resistance genes from the community sewage pool and become multidrug-resistant superbugs. In this regard, hospital sewage, which contains a large quantity of residual antibiotics, metals and disinfectants, is being recognized as a significant cause of antimicrobial resistance (AMR) origination and spread across the major centres of the world and is thus routinely investigated as a marker for tracing the origin of drug resistance. Therefore, in this study, an attempt has been made to identify and characterize the carbapenem-resistant microbes associated with integron genes amongst the organisms isolated from the effluent treatment plant (ETP) installed in a tertiary respiratory care hospital in Delhi, India.

Evaluation of 'TBDetect' sputum microscopy kit for improved detection of Mycobacterium tuberculosis: a multi-centric validation study.

Objectives: The present study aimed to evaluate the performance of the 'TBDetect' kit-based bio-safe fluorescent microscopy filter (BioFM-Filter) microscopy in comparison with direct smear microscopy and culture for the detection of pulmonary tuberculosis (TB) in a multi-centric setting in India.

Methods: The TBDetect kit enables sputum concentration through filtration using the BioFM-Filter for improved and bio-safe smear microscopy. We evaluated the performance of the TBDetect kit in a six-site multi-centric validation study on sputum collected from 2086 presumptive TB patients.

Genotypic characterization of 'inferred' rifampin mutations in GenoType MTBDRplus assay and its association with phenotypic susceptibility testing of Mycobacterium tuberculosis.

In GenoType MTBDRplus assay [line probe assay (LPA)], when Mycobacterium tuberculosis (M. tuberculosis) sample DNA fails to hybridize to at least 1 rpoB wild-type probe and any mutation probe, it is inferred as rifampin (RIF)-resistant. In this study, we sought to identify such 'inferred' mutations in M.

Recurrence of tuberculosis among newly diagnosed sputum positive pulmonary tuberculosis patients treated under the Revised National Tuberculosis Control Programme, India: A multi-centric prospective study.

Introduction: There is lack of information on the proportion of new smear-positive pulmonary tuberculosis (PTB) patients treated with a 6-month thrice-weekly regimen under Revised National Tuberculosis Control Programme (RNTCP) who develop recurrent TB after successful treatment outcome.

Objective: To estimate TB recurrence among newly diagnosed PTB patients who have successfully completed treatment and to document endogenous reactivation or re-infection. Risk factors for unfavourable outcomes to treatment and TB recurrence were determined.

Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears.

Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens.

Frequency of multi-drug resistance and mutations in Mycobacterium tuberculosis isolates from Punjab state of India.

Data regarding prevalence of multi-drug resistant tuberculosis (MDR-TB) and associated common mutations is scarce from Punjab region. The study was designed to determine rate of MDR-TB among presumptive MDR-TB from Punjab and mutation patterns using GenoType MTBDRplus assay. Total of 812 consecutive sputum samples were received from January 2012 to July 2013, from 14 districts of Punjab at the National Reference Laboratory at New Delhi for diagnosis of MDR-TB as hand holding activity.

Direct Detection of Rifampin and Isoniazid Resistance in Sputum Samples from Tuberculosis Patients by High-Resolution Melt Curve Analysis.

Drug-resistant tuberculosis (TB) is a major threat to TB control worldwide. Globally, only 40% of the 340,000 notified TB patients estimated to have multidrug-resistant-TB (MDR-TB) were detected in 2015. This study was carried out to evaluate the utility of high-resolution melt curve analysis (HRM) for the rapid and direct detection of MDR-TB in in sputum samples.

Drug resistance detection and mutation patterns of multidrug resistant tuberculosis strains from children in Delhi.

A total of 312 sputum samples from pediatric patients presumptive of multidrug resistant tuberculosis were tested for the detection of drug resistance using the GenoTypeMTBDRplus assay. A total of 193 (61.8%) patients were smear positive and 119 (38.

Isoniazid resistance among rifampicin-susceptible Mycobacterium tuberculosis isolates from tuberculosis patients.

Objective/background: With the introduction of novel molecular techniques that rely on rifampicin (RIF) susceptibility, resistance to isoniazid (INH) or other first-line drugs remains undetected. Such patients are prescribed first-line antituberculosis therapy and are on RIF monodrug therapy during the continuation phase, which may lead to therapeutic failure and emergence of multidrug resistance. We aimed to study INH resistance among RIF-susceptible Mycobacterium tuberculosis (MTB) isolates from retreatment patients.

Utility of MPT64 Antigen Detection for Rapid Confirmation of Mycobacterium tuberculosis Complex.

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.