The aim of this study was to investigate the usefulness of combining profiles obtained by using a line probe assay (LPA) originally intended to characterize the resistance of two major anti-tuberculosis drugs to the a...The aim of this study was to investigate the usefulness of combining profiles obtained by using a line probe assay (LPA) originally intended to characterize the resistance of two major anti-tuberculosis drugs to the association of spoligotyping and MIRU-VNTR, in order to improve its discriminatory power. For this purpose, 74 strains of Mycobacterium tuberculosis belonging to the same cluster after spoligotyping were further typed by using the 24 loci MIRU/VNTR. These strains were then tested by the GenoType MTBDRplus, and profiles obtained were analyzed within previously obtained clusters. The combination of spoligotying and MIRU-VNTR led to the consolidation of 56 of them (75.7%) in 9 clusters. Most of the strains (54, 96.4%) were multidrug resistant (MDR). From the 9 initial clusters, the addition of GenoType MTBDRplus helped to define 26 profiles including 11 unique profiles, and 3 original clusters remained undifferentiated. Results obtained express the relevance of combining this method which improved quite significantly the discriminatory power in typing Mycobacterium tuberculosis.展开更多
从2001年WHO/IUATLD全球抗结核药物耐药监测之内蒙古耐药监测结核菌1 114株中,选取经比例法药敏结果得到的耐多药(MDR)结核菌188株,利用Geno Type MTBDRplus方法检测该批菌株的RIF、INH耐药情况及其耐药基因突变形式。最终得到MDR菌株10...从2001年WHO/IUATLD全球抗结核药物耐药监测之内蒙古耐药监测结核菌1 114株中,选取经比例法药敏结果得到的耐多药(MDR)结核菌188株,利用Geno Type MTBDRplus方法检测该批菌株的RIF、INH耐药情况及其耐药基因突变形式。最终得到MDR菌株103(54.79%)株,单耐RIF菌株52(27.66%)株,单耐INH菌株10(5.32%)株,全敏感菌株20株,TUB条带缺失1株,kat G质控带缺失2株。RIF耐药菌株检测的是rpo B基因区,该基因突变菌株有155株;rpo B S531L突变菌株为49.68%(77/155)。INH耐药菌株检测的是kat G基因区和inh A基因启动子区,共113株,其中kat G基因突变菌株占79.65%(90/113),主要是S3-15T1突变;inh A基因突变菌株占22.12%(25/113)。因此,Geno Type MTBDRplus可用于内蒙古地区MDR结核菌的快速检测。其中rpo BS531L突变形式在RIF耐药菌株中最常见;在INH耐药菌株中,kat G基因突变较inh A基因突变常见,S315T1突变是INH耐药菌中常见的突变形式。展开更多
Background： The WHO recently has recommended the GenoType MTBDRph/s version 1.0 and MTBDRs/version 1.0 assays for widespread use in countries endemic with drug-resistant tuberculosis. Despite this, these assays have ...Background： The WHO recently has recommended the GenoType MTBDRph/s version 1.0 and MTBDRs/version 1.0 assays for widespread use in countries endemic with drug-resistant tuberculosis. Despite this, these assays have rarely been evaluated in China, where the burden of drug-resistant tuberculosis is among the highest globally. Methods： Mycobacterium tuberculosis clinical isolates were obtained between January 2008 and December 2008. Isolates were tested for drug resistance against rifampicin （RFP） and isoniazid （INH） using the GenoType MTBDRplus assay and drug resistance against ethambutol （EMB）, ofloxacin （OFX）, and kanamycin （KM） using the Genotype MTBDILsl assay. These results were compared with conventional drug-susceptibility testing （DST）. Results： Readable results were obtained from 235 strains by GenoType MTBDRphts assay. Compared to DST, the sensitivity of GenoType MTBDRplus assay to detect RFP, INH, and multidrug resistance was 97.7%, 69.9%, and 69.8%, respectively, whereas the specificity for detecting RFP, INH, and multidrug resistance was 66.7%, 69.2%, and 76.8%, respectively. The sensitivity and specificity of the GenoType MTBDRsl assay were 90.9% and 95.2% for OFX, 77.8% and 99.5% for KM, 63.7% and 86.4% for EMB, respectively. Mutations in codon S531L of the rpoB gene and codon S315T1 ofKatG gene were dominated in multidrug-resistant tuberculosis （MDR-TB） strains. Conclusions： In combination with DST, application of the GenoType MTBDRplus and MTBDRsl assays may be a useful supplementary tool to allow a rapid and sale diagnosis of multidrug resistance and extensively drug-resistant tuberculosis.展开更多
基金the support of the European Respiratory Society,Fellowship STRTF 413-2011.
文摘The aim of this study was to investigate the usefulness of combining profiles obtained by using a line probe assay (LPA) originally intended to characterize the resistance of two major anti-tuberculosis drugs to the association of spoligotyping and MIRU-VNTR, in order to improve its discriminatory power. For this purpose, 74 strains of Mycobacterium tuberculosis belonging to the same cluster after spoligotyping were further typed by using the 24 loci MIRU/VNTR. These strains were then tested by the GenoType MTBDRplus, and profiles obtained were analyzed within previously obtained clusters. The combination of spoligotying and MIRU-VNTR led to the consolidation of 56 of them (75.7%) in 9 clusters. Most of the strains (54, 96.4%) were multidrug resistant (MDR). From the 9 initial clusters, the addition of GenoType MTBDRplus helped to define 26 profiles including 11 unique profiles, and 3 original clusters remained undifferentiated. Results obtained express the relevance of combining this method which improved quite significantly the discriminatory power in typing Mycobacterium tuberculosis.
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 81302480）.
文摘Background： The WHO recently has recommended the GenoType MTBDRph/s version 1.0 and MTBDRs/version 1.0 assays for widespread use in countries endemic with drug-resistant tuberculosis. Despite this, these assays have rarely been evaluated in China, where the burden of drug-resistant tuberculosis is among the highest globally. Methods： Mycobacterium tuberculosis clinical isolates were obtained between January 2008 and December 2008. Isolates were tested for drug resistance against rifampicin （RFP） and isoniazid （INH） using the GenoType MTBDRplus assay and drug resistance against ethambutol （EMB）, ofloxacin （OFX）, and kanamycin （KM） using the Genotype MTBDILsl assay. These results were compared with conventional drug-susceptibility testing （DST）. Results： Readable results were obtained from 235 strains by GenoType MTBDRphts assay. Compared to DST, the sensitivity of GenoType MTBDRplus assay to detect RFP, INH, and multidrug resistance was 97.7%, 69.9%, and 69.8%, respectively, whereas the specificity for detecting RFP, INH, and multidrug resistance was 66.7%, 69.2%, and 76.8%, respectively. The sensitivity and specificity of the GenoType MTBDRsl assay were 90.9% and 95.2% for OFX, 77.8% and 99.5% for KM, 63.7% and 86.4% for EMB, respectively. Mutations in codon S531L of the rpoB gene and codon S315T1 ofKatG gene were dominated in multidrug-resistant tuberculosis （MDR-TB） strains. Conclusions： In combination with DST, application of the GenoType MTBDRplus and MTBDRsl assays may be a useful supplementary tool to allow a rapid and sale diagnosis of multidrug resistance and extensively drug-resistant tuberculosis.
