Enhancing diagnostic efficiency of pyrazinamide resistance in via modified MGIT assay and genotypic correlation.

Pyrazinamide (PZA) plays a crucial role in the treatment of both active and latent tuberculosis, particularly in regimens designed to treat drug-resistant TB. However, diagnosing resistance to PZA poses challenges for managing TB, highlighting the need for accurate detection methods. This study aims to address the challenges in detecting PZA resistance by modifying the standard MGIT960 PZA drug susceptibility testing method by optimizing the inoculum dilution.

Xpert MTB/RIF assay in the diagnosis of pulmonary tuberculosis in children in tertiary care setting in South India.

Xpert MTB/RIF is recommended for the diagnosis of tuberculosis (TB) in children. We determined the performance of Xpert MTB/RIF in the diagnosis of pulmonary TB in children. The characteristics of children influencing Xpert MTB/RIF positivity were explored.

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.

Early Microbiologic Markers of Pulmonary Tuberculosis Treatment Outcomes.

Earlier biomarkers of pulmonary tuberculosis (PTB) treatment outcomes are critical to monitor shortened anti-TB treatment (ATT). To identify early microbiologic markers of unfavorable TB treatment outcomes. We performed a subanalysis of 2 prospective TB cohort studies conducted from 2013 to 2019 in India.

Predictors of unfavorable responses to therapy in rifampicin-sensitive pulmonary tuberculosis using an integrated approach of radiological presentation and sputum mycobacterial burden.

Introduction: Despite the exalted status of sputum mycobacterial load for gauging pulmonary tuberculosis treatment and progress, Chest X-rays supplement valuable information for taking instantaneous therapeutic decisions, especially during the COVID-19 pandemic. Even though literature on individual parameters is overwhelming, few studies have explored the interaction between radiographic parameters denoting severity with mycobacterial burden signifying infectivity. By using a sophisticated approach of integrating Chest X-ray parameters with sputum mycobacterial characteristics, evaluated at all the three crucial time points of TB treatment namely pre-treatment, end of intensive phase and completion of treatment, utilizing the interactive Cox Proportional Hazards model, we aimed to precisely deduce predictors of unfavorable response to TB treatment.

Reprocessing of Contaminated MGIT 960 Cultures to Improve Availability of Valid Results for Mycobacteria.

Optimal recovery of mycobacteria from the contaminated liquid culture is a challenge. While alternative methods have been suggested to reduce the rate of contamination in the BACTEC MGIT 960 system, reprocessing the contaminated liquid culture improves recovery of . Among 793 MGIT cultures raised from as many sputum specimens after primary decontamination by the standard NaLC-NaOH method, valid results were available for 687 (86.

Characteristics of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome and its influence on tuberculosis treatment outcomes in persons living with HIV.

Objective: The influence of tuberculosis (TB)-immune reconstitution inflammatory syndrome (IRIS) on TB treatment outcomes and its risk factors were investigated among people with human immunodeficiency virus (HIV) and co-infected with TB.

Methods: Newly diagnosed, culture-confirmed, pulmonary TB patients with HIV and enrolled in a clinical trial (NCT00933790) were retrospectively analysed for IRIS occurrence. Risk factors and TB outcomes (up to 18 months after initiation of anti-TB treatment [ATT]) were compared between people who experienced IRIS (IRIS group) and those who did not (non-IRIS group).

Protein-protein interaction of Rv0148 with Htdy and its predicted role towards drug resistance in Mycobacterium tuberculosis.

Background: Mycobacterium tuberculosis resides inside host macrophages during infection and adapts to resilient stresses generated by the host immune system. As a response, M. tuberculosis codes for short-chain dehydrogenases/reductases (SDRs).

Validation of bedaquiline drug-susceptibility testing by BACTEC MGIT 960 system for .

Background: Bedaquiline (BDQ) is a new antituberculosis (TB) drug effectively used for the treatment of multidrug-resistant and extensively drug-resistant TB. However, the reports on drug-susceptibility testing (DST) for BDQ are scarce. The study aimed to validate and standardize BDQ DST by BACTEC MGIT 960 system for Mycobacterium tuberculosis.

Isolation and comparative genomics of Mycobacterium tuberculosis isolates from cattle and their attendants in South India.

The major human pathogen Mycobacterium tuberculosis is rarely reported to cause disease in other animals. Cases in livestock are thought to occur through contact with infected handlers, but previous studies evaluating putative livestock-human transmission used typing techniques with limited resolution. Here, we undertook cross-sectional surveillance for tuberculosis in 271 livestock handlers and 167 cattle on three farms in Chennai, India and defined the relatedness of cultured isolates using whole genome sequencing.

Whole-Genome Sequencing of a Strain Isolated from Cattle in Chennai, India.

Here, we report the isolation of from dairy cattle in Chennai, India. Spoligotyping assigned the isolate to spoligotype 587 (ST587), which belongs to This species was confirmed as using whole-genome sequencing.

Adequacy of examining one sputum specimen in tuberculosis drug resistance surveys.

Objective/background: Collection of one spot and one morning sputum specimen is recommended for tuberculosis (TB) drug resistance surveys. This was a retrospective analysis of Mycobacterium tuberculosis cultures isolated from two spot sputum specimens collected from smear positive TB patients in a TB drug resistance survey. It was conducted to understand the value of a second specimen.

Luciferase reporter phage phAE85 for rapid detection of rifampicin resistance in clinical isolates of Mycobacterium tuberculosis.

Objective: To evaluate luciferase reporter phage (LRP) phAE85 in rapid detection of rifampicin resistance in a region where TB is endemic.

Methods: One hundred and ninety primary isolates on Lowenstein-Jensen medium were tested. Middlebrook 7H9 complete medium with and without rifampicin at 2 μg/mL was inoculated with standard inoculum from suspensions of the clinical isolate.

Phage lysin to control the overgrowth of normal flora in processed sputum samples for the rapid and sensitive detection of Mycobacterium tuberculosis by luciferase reporter phage assay.

Background: Phage lysin, extracted from three bacteriophages was used in place of antibiotics to control the overgrowth of normal flora in processed sputum samples leading to the sensitive detection of Mycobacterium tuberculosis using diagnostic luciferase reporter phage assay (DLRPA).

Methods: A total of 129 sputum samples were processed by modified Petroff's method. Two Lowenstein Jensen slopes were inoculated from the processed sputum deposit thus obtained.

Effect of bacteriophage lysin on lysogens.

Objective: To study the effect of phage lysin on the growth of lysogens.

Methods: Sputum specimens processed by modified Petroff's method were respectively treated with phagebiotics in combination with lysin and lysin alone. The specimens were incubated at 37 °C for 4 days.

Phage lysin to supplement phagebiotics to decontaminate processed sputum specimens.

The overgrowth of normal flora escaping the action of sputum processing chemicals is the major problem in broth-based tuberculosis (TB) detection systems. The use of phages to control the overgrowth of normal flora in processed sputum samples has already been established. Phage lysin and its supplementation to phagebiotics for the effective control of normal flora in sputum specimens were evaluated.

Characterization of temperate phage Che12 and construction of a new tool for diagnosis of tuberculosis.

A temperate phage, Che12, able to infect Mycobacterium tuberculosis, was isolated from soil samples taken from tuberculosis sanatorium area in Chennai, India. The plaque morphology of this phage showed varying grades of turbidity on lawns of M. tuberculosis.

Construction and evaluation of luciferase reporter phages for the detection of active and non-replicating tubercle bacilli.

The luciferase reporter phages (LRP) show great promise for diagnostic mycobacteriology. Though conventional constructs developed from lytic phages such as D29 and TM4 are highly specific, they lack sensitivity. We have isolated and characterized Che12, the first true temperate phage infecting M.