Analytical and clinical validation of a novel MeltPlus TB-NTM/RIF platform for simultaneous detection of , and rifampicin resistance.

BACKGROUND

Rapid and accurate diagnosis of tuberculosis, particularly rifampin (RIF)-resistant tuberculosis (RR-TB) and (NTM), is essential for implementing appropriate proper therapy to benefit patients and improve TB/NTM patient management.

METHODS

In this study, we developed a novel MeltPlus MTB-NTM/RIF platform, designed to simultaneously detect (MTBC), NTM and RIF resistance. The platform was evaluated for its limit of detection (LOD) and specificity before clinical validation, followed by a prospective single-center study in patients with presumptive TB cases.

RESULTS

The calculated LOD for MTBC, NTM and RIF susceptibility was found to be 10.31 CFU/mL, 57.55 CFU/mL and 48.584 CFU/mL, respectively. The assay showed a sensitivity of 98.76% (95% CI: 96.41-99.74%) and a specificity of 94.42% (95% CI: 90.82-96.92%) for MTBC detection compared to the bacteriological TB standard. For NTM detection, the assay demonstrated a sensitivity of 91.98% (95% CI: 76.32-98.14%) and a specificity of 99.59% (95% CI: 98.54-99.95%). RIF resistance detection showed a sensitivity of 90.24% (95% CI:76.87-97.28%) and specificity of 95.98% (95% CI: 91.89-98.37%), with a high level of diagnostic agreement (: 0.8338) compared to GeneXpert. Sanger sequencing revealed that novel assay correctly classifies 98.6% of study cases as RIF resistant or susceptible, slightly higher that of GeneXpert.

DISCUSSION

These findings indicate that the novel MeltPlus MTB-NTM/RIF platform provides a rapid and accurate method for the simultaneously detecting MTBC, NTM, and RIF resistance, making it a promising tool for clinical TB/NTM diagnosis and management, further multi-center and field studies are recommended to validate its broader applicability.