# Evaluation of the Mycobacterium RealTime Kit Vircell (MRTVircell) Assay for Detecting Mycobacterium Species in Clinical Specimens

## TL;DR

This paper evaluates a new PCR test for detecting tuberculosis and other mycobacteria in clinical samples, showing it performs well compared to existing methods.

## Contribution

The first evaluation of the MRTVircell assay for detecting multiple mycobacterial species in clinical specimens under routine conditions.

## Key findings

- MRTVircell showed 96.95% concordance with Anyplex for detecting MTBC, NTM, and negatives.
- MRTVircell had higher sensitivity for NTM detection compared to Anyplex.
- MRTVircell demonstrated high specificity for both MTBC and NTM detection.

## Abstract

Rapid and accurate diagnosis of mycobacterial infections is crucial for guiding therapeutic decisions. This study presents the first evaluation of a novel molecular assay, the Mycobacterium RealTime PCR Kit Vircell (MRTVircell), a real-time PCR-based test designed for the specific detection of Mycobacterium tuberculosis complex (MTBC), Mycobacterium avium complex (MAC), Mycobacterium abscessus complex (MABC), and other nontuberculous mycobacteria (NTM) in both respiratory and non-respiratory samples. The evaluation was conducted under routine workflow conditions using 721 clinical specimens, including 559 respiratory and 162 non-respiratory samples. Among these, 5.69% were smear-positive, 6.38% were culture-positive for MTBC, and 9.85% were culture-positive for NTM. The performance of the MRTVircell was compared to both culture results and the Anyplex MTB/NTM real-time PCR assay. The two PCR systems demonstrated a 96.95% overall concordance rate for the detection of MTBC, NTM, and negative specimens. Based on culture as the reference method, the sensitivity, specificity, positive predictive value, and negative predictive value of the MRTVircell for MTBC detection were 80.43%, 99.64%, 94.87%, and 98.41%, respectively, while for Anyplex MTB/NTM (Seegene), these values were 76.09%, 99.64%, 94.59%, and 98.06%, respectively. For NTM detection, the sensitivity, specificity, positive predictive value, and negative predictive values were 28.17%, 99.29%, 83.33% and 91.63% for MRTVircell and 21.13%, 99.11%, 75%, and 91.67% for Anyplex MTB/NTM, respectively. MRTVircell is a rapid and reliable tool for the detection and differentiation of MTBC, MAC, MABC, and other NTM in clinical samples.