title: Evaluation of the GenoType MTBDRslVersion 2.0 Assay for Second-Line Drug Resistance Detection of Mycobacterium tuberculosis Isolates in South Africa.
abstract: Early detection of resistance to second-line antituberculosis drugs is important for the management of multidrug-resistant tuberculosis (MDR-TB). The GenoType MTBDRslversion 2.0 (VER 2.0) line probe assay has been redesigned for molecular detection of resistance-conferring mutations of fluoroquinolones (FLQ) (gyrAandgyrBgenes) and second-line injectable drugs (SLID) (rrsandeisgenes). The study evaluated the diagnostic performance of the GenoType MTBDRslVER 2.0 assay for the detection of second-line drug resistance compared with phenotypic drug susceptibility testing (DST), using the Bactec MGIT 960 system onMycobacterium tuberculosiscomplex isolates from South Africa. A total of 268 repository isolates collected between 2012 and 2014, which were rifampin monoresistant or MDR based on DST, were selected. MTBDRslVER 2.0 testing was performed on these isolates and the results analyzed. The MTBDRslVER 2.0 sensitivity and specificity indices for culture isolates were the following: FLQ, 100% (95% confidence interval [CI] 95.8 to 100%) and 98.9% (95% CI, 96.1 to 99.9%); SLID, 89.2% (95% CI, 79.1 to 95.6%) and 98.5% (95% CI, 95.7 to 99.7%). The sensitivity and specificity observed for individual SLID were the following: amikacin, 93.8% (95% CI, 79.2 to 99.2%) and 98.5% (95% CI, 95.5 to 99.7%); kanamycin, 89.2% (95% CI, 79.1 to 95.6%) and 98.5% (95% CI, 95.5 to 99.7%); and capreomycin, 86.2% (95% CI, 68.3 to 96.1%) and 95.9% (95% CI, 92.2 to 98.2%). An interoperator reproducibility of 100% and an overall interlaboratory performance of 93% to 96% were found. The overall improvement in sensitivity and specificity with excellent reproducibility makes the GenoType MTBDRslVER 2.0 a highly suitable tool for rapid screening of clinical isolates for second-line drug resistance for use in high-burden TB/HIV settings.
authors.affiliation: Centre for Tuberculosis, National Institute for Communicable Diseases, Johannesburg, South Africa yasming@nicd.ac.za.|Department of Clinical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Y
authors.initials: Y
authors.lastname: Gardee
authors.affiliation: Department of Clinical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: A W
authors.initials: AW
authors.lastname: Dreyer
authors.affiliation: Centre for Tuberculosis, National Institute for Communicable Diseases, Johannesburg, South Africa.|Department of Clinical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: H J
authors.initials: HJ
authors.lastname: Koornhof
authors.affiliation: Centre for Tuberculosis, National Institute for Communicable Diseases, Johannesburg, South Africa.
authors.forename: S V
authors.initials: SV
authors.lastname: Omar
authors.affiliation: Department of Clinical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|National Health Laboratory Service, Mycobacterial Referral Laboratory, Braamfontein, Johannesburg, South Africa.
authors.forename: P
authors.initials: P
authors.lastname: da Silva
authors.affiliation: Centre for Tuberculosis, National Institute for Communicable Diseases, Johannesburg, South Africa.
authors.forename: Z
authors.initials: Z
authors.lastname: Bhyat
authors.affiliation: Centre for Tuberculosis, National Institute for Communicable Diseases, Johannesburg, South Africa.|Department of Medical Microbiology, Faculty of Health Science, University of Pretoria, Pretoria, South Africa.
authors.forename: N A
authors.initials: NA
authors.lastname: Ismail
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005798:Genes, Bacterial; D060005:Genotyping Techniques / Q000379:methods*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D012680:Sensitivity and Specificity; D013019:South Africa
chemical_list: D000995:Antitubercular Agents
keywords: GenoType MTBDRsl version 2.0; LPA; MDR-TB; Mycobacterium tuberculosis; XDR-TB; drug-resistant TB; fluoroquinolones; line probe assay; molecular diagnostic testing; phenotypic drug susceptibility testing; second-line injectable drugs