title: Performance of the GenoType MTBDRplus assay (v2.0) and a new extended GenoType MTBDRsl assay (v2.0) for the molecular detection of multi- and extensively drug-resistant Mycobacterium tuberculosis on isolates primarily from Lithuania.
abstract: The emergence of extensively drug-resistant tuberculosis (XDR-TB) hampers infection control. To assess the performance of an extended rapid novel molecular analysis for the detection of resistance conferring mutations to fluoroquinolones (gyrA, gyrB genes) and aminoglycosides/cyclic peptides (16S rRNA rrs gene, eis promotor region) compared to phenotypic susceptibility and sequencing, 43 multidrug-resistant (MDR) and 10 susceptible clinical isolates were analyzed. Results were compared to a previous version. Molecular rifampin (rpoB gene) and isoniazid (katG gene, inhA promotor region) resistance was also analyzed. XDR-TB was confirmed in 13 (30%) MDR isolates. Molecular resistance was detected in 91% ofloxacin-, 83% aminoglycoside/cyclic peptide- and 100% kanamycin-resistant isolates. In conclusion, the novel assay is a useful supplement to phenotypic susceptibility testing in determining the presence of XDR-TB. Molecular kanamycin resistance detection was immensely improved compared to the previous version. Aminoglycoside/cyclic peptide susceptible isolates revealed eis promotor region resistance in 29%, reflecting low-level kanamycin susceptibility challenges.
authors.affiliation: International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark; Microbiological Diagnostics & Virology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark. Electronic address: dvb@ssi.dk.
authors.forename: Didi
authors.initials: D
authors.lastname: Bang
authors.affiliation: International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark.
authors.forename: Siri Rytcher
authors.initials: SR
authors.lastname: Andersen
authors.affiliation: Infectious Diseases and Tuberculosis Hospital, Vilnius University Hospital Santariskiu Klinikos, Lithuania; Department of Physiology, Biochemistry & Laboratory Medicine, Faculty of Medicine, Vilnius University, Lithuania.
authors.forename: Edita
authors.initials: E
authors.lastname: Vasiliauskienė
authors.affiliation: International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark.
authors.forename: Erik Michael
authors.initials: EM
authors.lastname: Rasmussen
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D005798:Genes, Bacterial; D005838:Genotype; D060005:Genotyping Techniques / Q000379:methods; D006801:Humans; D008097:Lithuania; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis*
chemical_list: D000995:Antitubercular Agents
keywords: Extensively drug-resistant; Genotype; Molecular; Multidrug-resistant; Mutation; Tuberculosis