Emergence of novel variants of gyrA and parC genes in a group of multiple resistant Klebsiella / 中华临床感染病杂志

ABSTRACT

Objective To investigate the distribution and variety of quinolone-resistance genes in a group of multiple resistant Klebsiella.Methods A total of 20 strains of multiple resistant Klebsiella were collected from inpatients in Huai' an First People' s Hospital of Nanjing Medical University during February 2010 and March 2012.Strains were identified by molecular identification,and quinolone target genes (gyrA,ParC) and quinolone-resistance genes mediated by mobile genetic elements (qnrA,qnrB,qnrS,aac (6′)-Ⅰ b-Cr,qepA) were analyzed with polymerase chain reaction (PCR).Results In 20 strains of Klebsiella,19 were Klebsiella pneumonia,and 1 was Klebsiella variicola.gyrA and parC genes were found in all 20 strains,and gyrA mutation was found in 11 strains (55.0％),andparC mutation was also found in 11strains (55.0％).aac(6′)-Ⅰ b-cr was positive in 10 strains (50.0％),qnrA was positive in 1 strain (5.0％),and qnrB was positive in 3 strains (15.0％).gyrA and parC in strain No.6 and No.10 were both novel variants (GenBank registration number:JX123016,JX123017,JX144393,JX144394).Conclusion Quinolone-resistance-determining region plays a key role in resistance to quinolones in this group of Klebsiella,and it is the first report on the emergence of novel variants of gyrA and parC in one Klebsiella pneumonia in China.