Publications by authors named "Sabira Tahseen"

Background: An accurate, rapid, non-sputum-based triage test for diagnosing tuberculosis (TB) is needed.

Methods: A prospective evaluation of the Xpert-MTB-HR cartridge, a prototype blood-based host-response mRNA signature assay, among individuals presenting with TB-like symptoms was performed in Pakistan and results were compared to three reference standards: Xpert MTB/RIF Ultra, bacteriological confirmation (Xpert MTB/RIF Ultra and/or culture positivity), and composite clinical diagnosis (clinician diagnosis, treatment initiation, Xpert MTB/RIF Ultra, and/or culture positivity). Analyses were conducted both for the entire study cohort and separately in the adolescent and young adult cohort (ages 10-24).

View Article and Find Full Text PDF

The discordance between phenotypic and molecular methods of rifampicin (RIF) drug susceptibility testing (DST) in poses a significant challenge, potentially resulting in misdiagnosis and inappropriate treatment. A comparison of RIF phenotypic and molecular methods for DST, including whole genome sequencing (WGS), may provide a better understanding of resistance mechanisms. This study aims to compare RIF DST in using two phenotypic and molecular methods including the GeneXpert RIF Assay (GX) and WGS for better understanding.

View Article and Find Full Text PDF
Article Synopsis
  • Pakistan has one of the highest rates of tuberculosis (TB) in the world, and a study was conducted to assess the prevalence of TB in adults and the risk of M. tuberculosis infection in children in Karachi, focusing on areas with and without prior active case-finding (ACF) activities.
  • The research involved surveys between March 2018 and May 2019, with almost 35,000 adults and over 1,500 children participating, revealing a higher prevalence of TB in areas with no prior ACF (421 cases per 100,000) compared to areas with prior ACF (279 cases per 100,000).
  • The findings indicated that ACF efforts in Korangi district likely reduced TB prevalence and transmission,
View Article and Find Full Text PDF

Background: Global tuberculosis (TB) drug resistance (DR) surveillance focuses on rifampicin. We examined the potential of public and surveillance () whole-genome sequencing (WGS) data, to generate expanded country-level resistance prevalence estimates (antibiograms) using in silico resistance prediction.

Methods: We curated and quality-controlled WGS data.

View Article and Find Full Text PDF

An accurate diagnosis of drug resistance in clinical isolates is an important step for better treatment outcomes. The current study observed a higher discordance rate of rifampicin resistance on Mycobacteria Growth Indicator Tube (MGIT) drug susceptibility testing (DST) than Lowenstein-Jenson (LJ) DST when compared with the sequencing. We detected a few novel mutations and their combination in rifampicin resistance isolates that were missed by MGIT DST and may be useful for the better management of tuberculosis (TB) treatment outcomes.

View Article and Find Full Text PDF

Extrapulmonary tuberculosis often poses a diagnostic challenge. This study aimed to assess the value of histological examination in diagnosing tuberculous lymphadenitis (LNTB) when performed simultaneously with rapid molecular assay (Xpert MTB/RIF) testing. People presumed to have LNTB were prospectively enrolled in a tertiary care hospital.

View Article and Find Full Text PDF

The optimal duration of treatment in different forms of extrapulmonary tuberculosis (EPTB) is not clearly defined. This study aimed to identify predictors of slow clinical response and extended anti-TB treatment in EPTB patients. Socio-demographic, clinical, and microbiological characteristics of EPTB patients registered for anti-TB treatment at a tertiary care hospital, were analysed for identification of predictors of extended treatment.

View Article and Find Full Text PDF

Bedaquiline Drug Resistance Emergence Assessment in Multidrug-resistant tuberculosis (MDR-TB) (DREAM) was a 5-year (2015 to 2019) phenotypic drug resistance surveillance study across 11 countries. DREAM assessed the susceptibility of 5,036 MDR-TB isolates of bedaquiline treatment-naive patients to bedaquiline and other antituberculosis drugs by the 7H9 broth microdilution (BMD) and 7H10/7H11 agar dilution (AD) MIC methods. Bedaquiline AD MIC quality control (QC) range for the H37Rv reference strain was unchanged, but the BMD MIC QC range (0.

View Article and Find Full Text PDF

Mycobacterium tuberculosis is a clonal pathogen proposed to have co-evolved with its human host for millennia, yet our understanding of its genomic diversity and biogeography remains incomplete. Here we use a combination of phylogenetics and dimensionality reduction to reevaluate the population structure of M. tuberculosis, providing an in-depth analysis of the ancient Indo-Oceanic Lineage 1 and the modern Central Asian Lineage 3, and expanding our understanding of Lineages 2 and 4.

View Article and Find Full Text PDF

Antibiotic resistance among bacterial pathogens poses a major global health threat. Mycobacterium tuberculosis complex (MTBC) is estimated to have the highest resistance rates of any pathogen globally. Given the low growth rate and the need for a biosafety level 3 laboratory, the only realistic avenue to scale up drug susceptibility testing (DST) for this pathogen is to rely on genotypic techniques.

View Article and Find Full Text PDF

Introduction: Rifampicin (RIF) is one of the most effective anti-tuberculosis first-line drugs prescribed along with isoniazid. However, the emergence of RIF resistance Mycobacterium tuberculosis (MTB) isolates is a major issue towards tuberculosis (TB) control program in high MDR TB-burdened countries including Pakistan. Molecular data behind phenotypic resistance is essential for better management of RIF resistance which has been linked with mutations in rpoB gene.

View Article and Find Full Text PDF

Objectives: Tuberculosis (TB) is a significant public health concern, and the basis of successful anti-tuberculosis treatment (ATT) rests on the complete eradication of live bacilli from a patient. This study was conducted to detect the live TB bacilli in Lowenstein Jensen culture media among exit cases of TB who were declared successfully treated, either cured or treatment completed.

Methods: This cross-sectional study was conducted across Pakistan.

View Article and Find Full Text PDF

Background: There is scarce knowledge on the prevalence of diseases caused by non-tuberculous mycobacteria (NTM) in Pakistan. In the absence of culture and identification, acid-fast bacilli (AFB) causing NTM disease are liable to be misinterpreted as tuberculosis (TB). Introduction of nucleic acid amplification testing for Mycobacterium tuberculosis complex (MTBC) offers improved diagnostic accuracy, compared with smear microscopy, and also assists in differentiating MTBC from other mycobacteria.

View Article and Find Full Text PDF

In its 2020 guidelines for the treatment of rifampicin-resistant TB (RR-TB), the WHO recommends all-oral fluoroquinolone-based regimens, with bedaquiline replacing the second-line injectable drugs (SLIDs). SLIDs were used for their strong acquired resistance-preventing activity. Data from three cohorts showed acquired bedaquiline resistance ranging between 2.

View Article and Find Full Text PDF

Background: Pakistan is fifth among high burden countries for tuberculosis. A steady increase is seen in extrapulmonary tuberculosis (EPTB), which now accounts for 20% of all notified TB cases. There is very limited information on the epidemiology of EPTB.

View Article and Find Full Text PDF

Two billion people are infected with , leading to 10 million new cases of active tuberculosis and 1.5 million deaths annually. Universal access to drug susceptibility testing (DST) has become a World Health Organization priority.

View Article and Find Full Text PDF

Background: The surveillance of drug resistance among tuberculosis (TB) patients is central to combatting the global TB epidemic and preventing the spread of antimicrobial resistance. Isoniazid and rifampicin are two of the most powerful first-line anti-TB medicines, and resistance to either of them increases the risk of treatment failure, relapse, or acquisition of resistance to other drugs. The global prevalence of rifampicin resistance is well documented, occurring in 3.

View Article and Find Full Text PDF

The 2018 World Health Organization (WHO) treatment guidelines for multidrug-/rifampicin-resistant tuberculosis (MDR/RR-TB) give preference to all-oral long regimens lasting for 18-20 months. The guidelines strongly recommend combining bedaquiline, levofloxacin (or moxifloxacin) and linezolid, supplemented by cycloserine and/or clofazimine. The effectiveness of this combination in a long regimen has not been tested in any study to date, with corresponding uncertainty.

View Article and Find Full Text PDF

We report on the first six cases of acquired resistance to bedaquiline in Pakistan. Seventy sequential isolates from 30 drug-resistant-tuberculosis patients on bedaquiline-containing regimens were retrospectively tested for bedaquiline resistance by MIC testing and by the detection of mutations in relevant genes. We documented cases failing therapy that developed specific mutations in and had increased MICs associated with cross-resistance to clofazimine during treatment.

View Article and Find Full Text PDF

Background: The World Health Organization recommends drug-susceptibility testing of Mycobacterium tuberculosis complex for all patients with tuberculosis to guide treatment decisions and improve outcomes. Whether DNA sequencing can be used to accurately predict profiles of susceptibility to first-line antituberculosis drugs has not been clear.

Methods: We obtained whole-genome sequences and associated phenotypes of resistance or susceptibility to the first-line antituberculosis drugs isoniazid, rifampin, ethambutol, and pyrazinamide for isolates from 16 countries across six continents.

View Article and Find Full Text PDF