Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Oct 29:14:1439099.
doi: 10.3389/fcimb.2024.1439099. eCollection 2024.

Development and preliminary assessment of the iFIND TBR: all-in- one molecular diagnostic assay for rapid detection of Mycobacterium tuberculosis and rifampicin resistance

Xichao Ou #  1 , Zexuan Song #  1   2 , Ruida Xing #  1 , Bing Zhao  1 , Shaojun Pei  1   3 , Chong Teng  4 , Lincai Zhang  5 , Qian Sun  6 , Fang Liu  5 , Hui Xia  1 , Yang Zhou  1 , Yang Zheng  1 , Yuanyuan Song  1 , Zhiguo Zhang  6 , Shengfen Wang  1 , Richard Anthony  7 , Yanlin Zhao  1
Affiliations

Development and preliminary assessment of the iFIND TBR: all-in- one molecular diagnostic assay for rapid detection of Mycobacterium tuberculosis and rifampicin resistance

Xichao Ou et al. Front Cell Infect Microbiol. .

Abstract

Introduction: Early and accurate diagnosis of tuberculosis (TB) is crucial for initiating timely treatment and preventing new infections. In this study, we introduced the iFIND TBR assay, an automated all-in-one tuberculosis detection approach that simultaneously detect Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance.

Methods: The limits of detection (LOD), sensitivity, specificity, and RIF-R rpoB mutation detection of the iFIND TBR were tested on Mycobacterium tuberculosis DNA or sputum samples spiked with known numbers of M.tuberculosis H37Rv. Frozen clinical samples from patients suspected of having TB were also tested.

Results: The LOD of the iFIND TBR for MTB detection were 13.34 CFU/ml (95% CI, 11.71-16.47), and for RIF resistance was 109.79CFU/mL (95% CI, 95-138.19). The iFIND TBR assay accurately distinguish MTB strains from non-tuberculous mycobacteria (NTM) without any cross reactivity. Testing on 157 clinical sputum samples, compared with the bacteriologically TB standard, the overall sensitivity and specificity of the iFIND TBR was 100% (95%CI, 94.64, 100) and 85.29% (95% CI, 74.61, 92.72), respectively. When assessing RIF susceptibility, the iFIND TBR achieved a sensitivity of 98.15% (95% CI, 90.11-99.95) and a specificity of 85.71% (95% CI, 67.33-95.97), compared with phenotypic drug susceptibility testing. Discordant RIF susceptibility results were more frequently observed in samples exhibiting heteroresistance.

Discussion: These findings demonstrate that iFIND TBR assay performs well in detecting TB and RIF resistance, and shows promise as a point-of-care tool in resource-limited areas.

Keywords: Mycobacterium tuberculosis; rapid detection; rifampicin resistance; the iFIND TBR; tuberculosis.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Schematic of the iFIND workflow.
Figure 2
Figure 2
Detection of rpoB gene mutations associated with RIF resistance in the iFIND TBR. The peaks for wild-type M. tuberculosis (A) identify a test sample as rifampin susceptible. The shift in one or more of the peaks away from the wild type’s melting temperature (B–E), identify a sample as a rpoB mutant and rifampin resistant. The shift in the melt peak is indicated by arrows.
Figure 3
Figure 3
The limit of detection (LOD) for M. tuberculosis H37Rv by iFIND TBR. (A) The limit of detection of tuberculosis detection. (B) The limit of detection of rifampin susceptibility.
Figure 4
Figure 4
Heteroresistance detection of the iFIND TBR. Samples containing 500 CFU/ml (A–D) and 250 CFU/ml (E–H) of M. tuberculosis DNA were created using different proportions of wild-type and rifampin-resistant rpoB S531L mutant DNA.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. WHO . (2014). “WHO guidelines approved by the guidelines review committee,” in Xpert mtb/rif implementation manual: technical and operational ‘how-to’; practical considerations (Geneva: World Health Organization; ). - PubMed
    1. Chakravorty S., Simmons A. M., Rowneki M., Parmar H., Cao Y., Ryan J., et al. . (2017). The new Xpert MTB/RIF ultra: improving detection of mycobacterium tuberculosis and resistance to rifampin in an assay suitable for point-of-care testing. mBio 8(4). doi: 10.1128/mBio.00812-17 - DOI - PMC - PubMed
    1. Consortium U. T., Heyckendorf J., Georghiou S. B., Frahm N., Heinrich N., Kontsevaya I., et al. . (2022). Tuberculosis treatment monitoring and outcome measures. New interest new strategies. Ahead of Print. doi: 10.1128/cmr.00227-21 - DOI - PMC - PubMed
    1. Deng Y., Ma Z., Su B., Bai G., Pan J., Wang Q., et al. . (2023). Accuracy of the InnowaveDX MTB/RIF test for detection of Mycobacterium tuberculosis and rifampicin resistance: a prospective multicentre study. Emerg. Microbes Infect. 12 (1), 2151382. doi: 10.1080/22221751.2022.2151382 - DOI - PMC - PubMed
    1. He W., Tan Y., Liu C., Wang Y., He P., Song Z., et al. . (2022). Drug-resistant characteristics, genetic diversity, and transmission dynamics of rifampicin-resistant mycobacterium tuberculosis in Hunan, China, revealed by whole-genome sequencing. Microbiol. Spectr. 10 (1), e0154321. doi: 10.1128/spectrum.01543-21 - DOI - PMC - PubMed

MeSH terms

LinkOut - more resources