Study on the mutation characteristics of streptomycin genes of Multidrug-Resistant Mycobacterium Tuber-culosis in Jiangxi Province / 实用医学杂志

ABSTRACT

Objective To understand the molecular characteristics of Streptomycin(SM)resistance in multidrug-resistant tuberculosis(MDR-TB)in Jiangxi Province,and to explore the relationship between SM resistant genes(rpsL,rrs and gidB)mutations and SM resistant phenotypes in Beijing genotype TB.Methods 106 non-replicated MDR-TB isolates were collected from Gaoxin Branch of The First Affiliated Hospital of Nanchang University and Jiangxi Provincial Chest Hospital from January to December 2021,and tested for drug-resistance phenotypes,whether they were Beijing genotype or not and the characteristics of rpsL,rrs and gidB gene mutations.Chi-square test was performed to determine whether rpsL,rrs and gidB mutations were related to genotypes and drug-resistance phenotypes.Results Among 106 cases of MDR-TB,76 cases were resistant to SM.A total of 58 cases had rpsL 43A>G mutation,8 cases had 88A>G mutation,5 cases had rrs mutation,and 3 cases had gidB mutation.Statistical analysis showed that the coincidence rate of gene mutation and phenotypic drug-resistance detection was 89.6%,and the specificity and sensitivity were 86.7%and 90.8%,respectively.The isolated rate of Beijing genotype TB was 88.7%,and the drug-resistant gene mutations were mainly concentrated in rpsL and rrs,while the drug-resistant mutations of non-Beijing genotype were mainly concentrated in gidB;in addition,Beijing genotype bacteria were more prone to gene mutations(P = 0.013),but there was no difference in phenotypic drug-resistance.Conclusions Mutations in rpsL,rrs,and gidB genes have a good coincidence rate with phenotypic drug-resistance,and molecular biology can be used to detect directly drug-resistance genes to predict bacterial resistance;TB genotypes are strongly associated with streptomycin resistance characteristics.