Rapid molecular testing for NTM diagnosis

Mahfuzah Mohamad
National Public Health Laboratory, Sungai Buloh, Selangor, Malaysia

Nontuberculous mycobacteria (NTM) are increasingly recognised as significant causes of pulmonary and extrapulmonary diseases. Thus, accurate and timely species identification is very important, as treatment regimens and drug resistance profiles vary between species and subspecies. Conventional culture-based methods are time-consuming, therefore delaying clinical decisions. Currently, rapid molecular testing and mass spectrometry have emerged as valuable tools to complement conventional diagnostics, offering improved turnaround time and species-level identification.

This presentation will provide an overview of molecular and proteomic platforms for NTM diagnosis, including line probe assays, real-time PCR, multiplex PCR assays, targeted next-generation sequencing (NGS), and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). The presentation will also cover practical application in diagnostic laboratories, focusing on detection sensitivity, species coverage, turnaround time, and limitations. Special emphasis will be given to clinically relevant species such as the Mycobacteroides abscessus complex, where subspecies-level identification and resistance gene detection (e.g., erm(41), rrl mutations) have direct therapeutic implications.

This session aims to share practical experience from a national reference laboratory perspective, highlighting challenges and opportunities in adopting these technologies for NTM diagnosis in high-burden settings.