Combined detection of 62 drug-resistant gene elements and detection of gyrA gene mutation in multidrug-resistant Klebsiella pneumoniae
QIU Jiang1, ZHANG Jie1, SUN Yang1, MI Zu-huang2
1.Department of Medical Laboratory, Hubei Jianghan Oil Field General Hospital, Qianjiang 433121,China; 2. Wuxi Clon-Gen Techonology Institution, Wuxi 214026,China
Abstract:We investigated the distribution of resistant determinants in a group of drug-resistant Klebsiella pneumoniae (K. pneumoniae), and the relationships of strains. Twenty-five strains of K. pneumoniae were collected from Hubei Jianghan Oil Field General Hospital in 2016-2017. gyrA sequencing and BLASTn algorithm were used to identify K. pneumonia, 35 kinds of beta-lactamase genes, 15 kinds of resistant genes to aminoglycosides, a kind of resistant genes to quinolones, 11 kins of genetic markers of mobile genetic elements were analyzed by PCR. Then, gene mutations were analyzed by DNA sequencing. At last, the results were analyzed by cluster analysis. In addition, sample cluster analysis was performed (UPGMA method) by 62 kinds of resistant determinants. Results showed that resistance rates of 25 K. pneumoniae to carbapenems were low, but resistance rates to other 8 kinds of antibiotics were higher. Beta lactamase genes were positive in every strain (total positive rate 100%); resistant genes to aminoglycosides were positive in 24 strains (total positive rate 96%); resistant gene to quinolones, gyrA mutation, were positive in 20 strains (mutation rate 80%); genetic markers of mobile genetic elements were positive in every strain (total positive rate 100%). In addition, 5 kinds of beta-lactamase genes (blaTEM, blaLAP, blaKPC, blaDHA group, blaOXA-1 group), 6 kinds of aminoglycoside resistance genes (aac(3)-Ⅱ, aac(6’)-Ⅰb, ant(3”)-Ⅰ, aph3’-Ⅰ, aadA5, rmtB), were positive. The same kind of 83rd codon of gyrA mutation existed in 20 strains, but no 87th codon of gyrA mutation existed. And 8 kinds of mobile genetic elements (intⅠ1, tnpU, tnp513, ISEcp1, IS26, IS903, ISKpn6, trbC were positive.), and positive rates were high. Sample cluster analysis showed that 25 strains might be divided into cluster A and cluster B, and clone transmission existed. The 2 clones were in cluster A: strain No. 2-3-5-16, 13-14, while a clone was in cluster B: strain No.19-20.It is suggested that a variety of beta-lactamase genes, aminoglycoside resistance genes, gyrA mutation and mobile genetic elements in this group of K. pneumonia could play a key role in resistant to 10 antimicrobial agents. Three clones are in the group of K. pneumonia, which might suggests that nosocomial infection exist.
丘江, 张洁, 孙杨, 糜祖煌. 多重耐药肺炎克雷伯菌62种耐药基因元件的检测与gyrA基因突变的发现[J]. 中国人兽共患病学报, 2019, 35(6): 539-544.
QIU Jiang, ZHANG Jie, SUN Yang, MI Zu-huang. Combined detection of 62 drug-resistant gene elements and detection of gyrA gene mutation in multidrug-resistant Klebsiella pneumoniae. Chinese Journal of Zoonoses, 2019, 35(6): 539-544.