Second-Line Drug Susceptibility Testing (SL-DST) for Tuberculosis:Introduction, Principle, Procedure, Result-Interpretation, and Keynotes

Phenotypic drug susceptibility testing (DST) of Mycobacterium tuberculosis using the BACTEC MGIT 960 system

Introduction Second-line drug susceptibility testing (SL-DST) for tuberculosis is a crucial laboratory procedure designed to detect resistance to anti-TB drugs used when first-line treatment fails (i.e., multidrug-resistant TB – MDR-TB).  Principle SL-DST measures the susceptibility of Mycobacterium tuberculosis to specific agents by determining the Critical …

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Xpert MTB/RIF: Introduction, Principle, Procedure, Result-Interpretation, Uses, and Keynotes

GeneXpert® Xpert® MTBRIF Test Result- MTB Detected (Very Low) and Rifampicin Resistance Not Detected

Introduction The Xpert MTB/RIF assay is an automated, cartridge-based molecular test used to detect Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance, the most potent first-line anti-TB drug. Endorsed by the WHO in 2010, the Xpert MTB/RIF assay revolutionized TB diagnosis by providing results in less than two …

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IGRA (Interferon-Gamma Release Assay) Test-Introduction, Principle, Test Requirement, Procedure, Result-Interpretation, and Keynotes

Introduction An Interferon-Gamma Release Assay (IGRA) is a modern blood test used to identify if a person is infected with Mycobacterium tuberculosis. It is primarily used to detect latent TB infection (LTBI) and to aid in the diagnosis of active tuberculosis disease.  Principle The test is based on the fact …

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