EVALUTION OF GENOTYPE® MTBDRPLUS ASSAY FOR DETECTION OF RIFAMPICIN RESISTANCE IN MULTI DRUG RESISTANCE MYCOBACTERIUM TUBERCULOSIS COMPLEX STRAINS

Back to Page Authors: Esra Yildirim Servi, Meltem Uzun

Keywords: tuberculosis, rpoB, mycobacterium, resistance, genotype MTBDRplus

Abstract: Resistance profiles of Mycobacterium tuberculosis strains and gene mutations causing resistance are being investigated throughout the world and mutation zones of strains are being researched on the country basis. In this study, 25 multidrug resistant (MDR) Mycobacterium tuberculosis clinical strains collected between January 2001-December 2011 were used and gene mutations causing rifampicin (RIF) resistance were investigated by GenoType® MTBDRplus and the results of resistance obtained by GenoType® MTBDRplus were compared with the results of BACTEC 460 TB system. There were 96% compliance between GenoType® MTBDRplus and BACTEC 460 TB system for the detection of RIF resistance. The most frequent mutation zone in MDR strains was rpoB S531L promotor zone (13 strains, 52%). The other rpoβ gene mutations were H526Y (3strains, 12%) and H526D (3 strains, 12%), while 5 strains had Δ2-Δ5 mutations (20%) in the wild type probes. There was no mutation only one strain (4%) by GenoType®MTBDRplus but it was found to be as resistant to rifampicin by the BACTEC 460 TB system. In conclusion, GenoType® MTBDRplus showed good compliance with the BACTEC 460 TB system in the detection of rifampicin resistance and it was thought that GenoType® MTBDRplus might be an effective and reliable test for the susceptibility testing of rifampicin in MDR-TB patients. Additionally, this technique also provided a significant advantage in terms of time.