Prevalence and Molecular Characteristics of Drug-Resistant Mycobacterium tuberculosis in Hunan, China

Abstract

ABSTRACTTo determine the prevalence and molecular characteristics of drug-resistant tuberculosis in Hunan province, drug susceptibility testing and spoligotyping methods were performed among 171M. tuberculosisisolates. In addition, the mutated characteristics of 12 loci, includingkatG,inhA,rpoB,rpsL, nucleotides 388 to 1084 of therrsgene [rrs(388–1084)],embB,pncA,tlyA,eis, nucleotides 1158 to 1674 of therrsgene [rrs(1158–1674)],gyrA, andgyrB, among drug-resistant isolates were also analyzed by DNA sequencing. Our results indicated that the prevalences of isoniazid (INH), rifampin (RIF), streptomycin (SM), ethambutol (EMB), pyrazinamide (PZA), capreomycin (CAP), kanamycin (KAN), amikacin (AKM), and ofloxacin (OFX) resistance in Hunan province were 35.7%, 26.9%, 20.5%, 9.9% 15.2%, 2.3%, 1.8%, 1.2%, and 10.5%, respectively. The previously treated patients presented significantly increased risks for developing drug resistance. The majority ofM. tuberculosisisolates belonged to the Beijing family. Almost all the drug resistance results demonstrated no association with genotype. The most frequent mutations of drug-resistant isolates werekatGcodon 315 (katG315),inhA15,rpoB531,rpoB526,rpoB516,rpsL43,rrs514,embB306,pncA96,rrs1401,gyrA94, andgyrA90. These results contribute to the knowledge of the prevalence of drug resistance in Hunan province and also expand the molecular characteristics of drug resistance in China.