A-248 Evaluation of NextGene™ MTB/NTM Detection Kit for Detection of Mycobacterium tuberculosis Complex and Nontuberculous Mycobacteria in Sputum and Culture Specimens

Abstract

Abstract Background Tuberculosis, an infectious disease, is a major cause of deteriorating health, and, until SARS-CoV-2 (COVID-19) became a pandemic disease, a major cause of death worldwide. The recently developed NextGene™ MTB/NTM Detection Kit is designed for detection of Mycobacterium tuberculosis complex (MTB) using IS6110 genes and MPB64 genes, and for detection of nontuberculous mycobacteria (NTM) using 16S rRNA genes for resolution of false positive and false negative results, and for development of more sensitive and specific real-time PCR products. The purpose of this study is to examine the clinical sensitivity and specificity of the NextGene™ MTB/NTM Detection Kit in order to verify its clinical efficacy. Methods A total of 446 residual clinical specimens were obtained from 274 sputum and 172 culture samples collected from July to August 2021. Diagnostic tests were performed in order to confirm that these residual samples were positive and negative; 344 specimens were positive for MTB or NTM, and 102 specimens were confirmed as negative for both MTB and NTM. Measurement of positive/negative percent agreement values and kappa coefficients was performed for comparison of diagnostic performance between the NextGene™ and Advansure assays. Positive and negative controls were included in each run. Results Of the 446 samples (274 sputum and 172 culture samples), 344 specimens showed a positive result and 102 specimens showed a negative result. Results of the comparison tests were all consistent for detection of MTB and NTM. Both MTB and NTM met the criterion for evaluation of target validity of kappa value 0.8 or higher in sputum and culture samples. Results of the evaluation of clinical sensitivity and specificity were consistent with both clinical diagnoses. Conclusion This study was conducted in order to examine the clinical sensitivity and specificity of the NextGene™ MTB/NTM Detection Kit in order to verify its clinical validity. Residual samples from sputum and culture specimens from patients who were suspected being infected that were confirmed positive or negative for MTB and NTM were used in this study with the goal of establishing the already commercially available licensed product as a control reagent for comparative analysis of the clinical performance of the NextGene™ MTB/NTM Detection Kit. Compared to existing kits that are widely used, consistent results from comparison of the NextGene™ MTB/NTM Detection Kit have been reported with comparable clinical sensitivity and specificity, thus it is regarded as showing the same performance.