| Abstract [eng] |
SUMMARY Comparative Analysis of Mutations Associated with Resistance to Anti-tuberculsis Drugs in Mycobacterium Tuberculosis Isolates Authors of Master’s degree scientific research work: Vaida Baliutytė Head of Master’s degree scientific research work: Dr Silvija Kiveryte Consultant of Master’s degree scientific research work: Edita Vasiliauskienė Vilnius 2017 The aim of the Thesis: Evaluation of Mycobacterium tuberculosis resistance to second line anti-tuberculosis drugs and associated gene mutations, tested by Anyplex TMII MTB/XDR assay. Assesment was based on relative analysis to results of phenotypic methods. Materials and methods. Study was conducted in 2016-2017 at Vilnius University Hospital Santaros Hospital Center of Laboratory Medicine Tuberculosis Laboratory and Microbiology Laboratory. 66 M. tuberculosis strains isolated from Lithuanian patients pulmonary sputum samples were used in the study. All strains were examined using phenotypic drug susceptibility testing to second line anti-tuberculosis drugs with following genomic DNA extraction. Drug-resistance and associated gene mutations detected by RT-PGR at molecular diagnostic laboratory. Results and conclusions. RT-PCR analysis showed that almost half of the samples were resistant to fluoroquinolones and aminoglycosides (AMK, KAN). KAP-resistant mycobacteria were not identified. RT-PCR sensitivity to fluoroquinolone was 81%, specificity - 86%. Sensitivity to aminoglycosides - 81%, specificity - 67%. gyrA gene was detected in majority 31 (47%) isolates and eis gene promoter mutations in 29 (44%) isolates. rrs (A1401G/G1484T) gene mutation were indentified in 6 (9%) isolates. C1402T mutation was not detected. A comparison of phenotypic and RT-PCR showed good results for FQ resistance results, however specificity to aminoglycosides (AMK, KAN) were suboptimal. In conclusion, the new assay showed good results, however due to the limited number of gene-target specificity were lower, iso its use in clinical practice is uncertain. The obtained results must be confirmed by classical phenotypic method. |
