Mycobacterium tuberculosis
ImmunoassaysImpact of T-Cell Xtend on T-SPOT.TB Assay in High-Risk Individuals after Delayed Blood Sample ProcessingT-SPOT.TB (T-SPOT) is an interferon gamma release assay (IGRA) used to detect infection with Mycobacterium tuberculosis based on the number of spot-forming T cells; however, delays in sample processing have been shown to reduce the number of these spots that are detected following laboratory processing. Adding T-Cell Xtend (XT) into blood samples before...
Mycobacteriology and Aerobic ActinomycetesMycobactericidal Effects of Different Regimens Measured by Molecular Bacterial Load Assay among People Treated for Multidrug-Resistant Tuberculosis in TanzaniaRifampin or multidrug-resistant tuberculosis (RR/MDR-TB) treatment has largely transitioned to regimens free of the injectable aminoglycoside component, despite the drug class’ purported bactericidal activity early in treatment. We tested whether Mycobacterium tuberculosis
Mycobacteriology and Aerobic ActinomycetesLow-Level Rifampin Resistance and rpoB Mutations in Mycobacterium tuberculosis: an Analysis of Whole-Genome Sequencing and Drug Susceptibility Test Data in New YorkRapid and reliable detection of rifampin (RIF) resistance is critical for the diagnosis and treatment of drug-resistant and multidrug-resistant (MDR) tuberculosis. Discordant RIF phenotype/genotype susceptibility results remain a challenge due to the presence of rpoB mutations that do not confer high levels of RIF resistance, as have been exhibited in strains with mutations such as Ser450Leu.
Mycobacteriology and Aerobic ActinomycetesXpert MTB/XDR: a 10-Color Reflex Assay Suitable for Point-of-Care Settings To Detect Isoniazid, Fluoroquinolone, and Second-Line-Injectable-Drug Resistance Directly from Mycobacterium tuberculosis-Positive SputumWe describe the design, development, analytical performance, and a limited clinical evaluation of the 10-color Xpert MTB/XDR assay (CE-IVD only, not for sale in the United States). This assay is intended as a reflex test to detect resistance to isoniazid (INH), fluoroquinolones (FLQ), ethionamide (ETH), and second-line injectable drugs (SLIDs) in unprocessed sputum samples and concentrated sputum sediments which are positive for...
Mycobacteriology and Aerobic ActinomycetesComparative Analytical Evaluation of Four Centralized Platforms for the Detection of Mycobacterium tuberculosis Complex and Resistance to Rifampicin and IsoniazidFailure to rapidly identify drug-resistant tuberculosis (TB) increases the risk of patient mismanagement, the amplification of drug resistance, and ongoing transmission. We generated comparative analytical data for four automated assays for the detection of TB and multidrug-resistant TB (MDR-TB): Abbott RealTime MTB and MTB RIF/INH (Abbott), Hain Lifescience FluoroType MTBDR (Hain), BD Max MDR-TB (BD), and Roche cobas MTB and...
Mycobacteriology and Aerobic ActinomycetesGenSeizer: a Multiplex PCR-Based Targeted Gene Sequencing Platform for Rapid and Accurate Identification of Major Mycobacterium SpeciesMycobacterium tuberculosis and nontuberculous mycobacterium (NTM) infections often exhibit similar clinical symptoms. Timely and effective treatment relies on the rapid and accurate identification of species and resistance genotypes.
Mycobacteriology and Aerobic ActinomycetesAssessing Nanopore Sequencing for Clinical Diagnostics: a Comparison of Next-Generation Sequencing (NGS) Methods for Mycobacterium tuberculosisNext-generation sequencing technologies are being rapidly adopted as a tool of choice for diagnostic and outbreak investigation in public health laboratories. However, costs of operation and the need for specialized staff remain major hurdles for laboratories with limited resources for implementing these technologies. This project aimed to assess the feasibility of using Oxford Nanopore MinION whole-genome sequencing data of...
Mycobacteriology and Aerobic ActinomycetesCharacterization of Genomic Variants Associated with Resistance to Bedaquiline and Delamanid in Naive Mycobacterium tuberculosis Clinical StrainsThe role of mutations in genes associated with phenotypic resistance to bedaquiline (BDQ) and delamanid (DLM) in Mycobacterium tuberculosis complex (MTBc) strains is poorly characterized. A clear understanding of the genetic variants’ role is crucial to guide the development of molecular-based drug susceptibility testing (DST). In this work, we analyzed all mutations...
Mycobacteriology and Aerobic ActinomycetesDNA Thermo-Protection Facilitates Whole-Genome Sequencing of Mycobacteria Direct from Clinical SamplesMycobacterium tuberculosis is the leading cause of death from bacterial infection. Improved rapid diagnosis and antimicrobial resistance determination, such as by whole-genome sequencing, are required. Our aim was to develop a simple, low-cost method of preparing DNA for sequencing direct from M....
Mycobacteriology and Aerobic ActinomycetesAn Optimal Diagnostic Strategy for Tuberculosis in Hospitalized HIV-Infected Patients Using GeneXpert MTB/RIF and Alere Determine TB LAM AgThe diagnosis of tuberculosis (TB) in HIV-infected patients is challenging. Both a urinary lipoarabinomannan (LAM) test (Alere TB LAM) and GeneXpert-MTB/RIF (Xpert) are useful for the diagnosis of TB. However, how to optimally integrate Xpert and LAM tests into clinical practice algorithms remain unclear. We performed a post hoc analysis of 561 HIV-infected sputum-expectorating patients (median CD4 count of 130 cells/ml) from a...