Evaluation of Colorimetric Nitrate Reductase Assay in Liquid Medium for Detection of Resistance to First-line Antitubercular Drugs.

Background: On a global scale, India holds the distinction of having the greatest number of tuberculosis (TB) cases caused by Mycobacterium tuberculosis (MTB) complex. The study aimed at evaluating the sensitivity, specificity, accuracy, cost, rapidity, and feasibility of the performance of the colorimetric nitrate reductase-based antibiotic susceptibility (CONRAS) test against the indirect proportion method (IPM) on Lowenstein-Jensen media as the gold standard.

Methods: A comparative cross-sectional study was performed on 51 MTB isolates.