Diagnostic accuracy of the FluoroType MTB and MTBDR VER 2.0 assays for the centralized high-throughput detection of Mycobacterium tuberculosis complex DNA and isoniazid and rifampicin resistance

Anzaan Dippenaar; Brigitta Derendinger; Tania Dolby; Natalie Beylis; Paul D van Helden; Grant Theron; Robin M Warren; Margaretha de Vos

doi:10.1016/j.cmi.2021.04.022

Diagnostic accuracy of the FluoroType MTB and MTBDR VER 2.0 assays for the centralized high-throughput detection of Mycobacterium tuberculosis complex DNA and isoniazid and rifampicin resistance

Clin Microbiol Infect. 2021 Sep;27(9):1351.e1-1351.e4. doi: 10.1016/j.cmi.2021.04.022. Epub 2021 Apr 30.

Authors

Anzaan Dippenaar¹, Brigitta Derendinger¹, Tania Dolby², Natalie Beylis³, Paul D van Helden¹, Grant Theron¹, Robin M Warren¹, Margaretha de Vos⁴

Affiliations

¹ Department of Science and Innovation-National Research Foundation Centre for Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa.
² National Health Laboratory Services, Green Point, Cape Town, South Africa.
³ National Health Laboratory Services, Green Point, Cape Town, South Africa; Division of Medical Microbiology, University of Cape Town, South Africa.
⁴ Department of Science and Innovation-National Research Foundation Centre for Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa. Electronic address: margaretha.devos@finddx.org.

PMID: 33933566
DOI: 10.1016/j.cmi.2021.04.022

Abstract

Objectives: To evaluate the accuracy of two new molecular diagnostic tests for the detection of drug-resistant tuberculosis, the FluoroType MTB and MTBDR VER 2.0 assays, in combination with manual and automated DNA extraction methods.

Methods: Sputa from 360 Xpert Ultra Mycobacterium tuberculosis complex (MTBC)-positive patients and 250 Xpert Ultra MTBC-negative patients were tested. GenoType MTBDRplus served as reference for MTBC and drug resistance detection. Sanger sequencing was used to resolve discrepancies.

Results: FluoroType MTB VER 2.0 showed similar MTBC sensitivity compared with FluoroType MTBDR VER 2.0 (manual DNA extraction: 91.6% (294/321) versus 89.8% (291/324); p 0.4); automated DNA extraction: 92.1% (305/331) versus 87.7% (291/332); p 0.05)). FluoroType MTBDR VER2.0 showed comparable diagnostic accuracy to FluoroType MTBDR VER1.0 as previously reported for the detection of MTBC and rifampicin and isoniazid resistance.

Conclusions: The FluoroType MTB and MTBDR VER 2.0 assays together with an automated DNA extraction and PCR set-up platform may improve laboratory operational efficiency for the diagnosis of MTBC and resistance to rifampicin and isoniazid and show promise for the implementation in a centralized molecular drug susceptibility testing model.

Keywords: Diagnostic; Drug resistance; Isoniazid; Molecular diagnostic; Multidrug-resistant tuberculosis; Rifampicin; Tuberculosis.

Publication types

Comparative Study
Evaluation Study

MeSH terms

Antitubercular Agents / pharmacology
DNA, Bacterial / isolation & purification
Drug Resistance, Bacterial*
Humans
Isoniazid* / pharmacology
Microbial Sensitivity Tests*
Molecular Diagnostic Techniques
Mycobacterium tuberculosis* / drug effects
Mycobacterium tuberculosis* / genetics
Rifampin* / pharmacology
Sensitivity and Specificity
Tuberculosis / diagnosis
Tuberculosis / microbiology

Substances

Antitubercular Agents
DNA, Bacterial
Isoniazid
Rifampin