绍兴地区肠道外气单胞菌对喹诺酮类抗菌药物的耐药机制  

Mechanism study of quinolones resistance in the extraintestinal Aeromonas strains in Shaoxing, Zhejiang

作　　者：何秋丽[1] 梁美春[1] 茅国峰[1] He Qiuli;Liang Meichun;Mao Guofeng(Shaoxing People’s Hospital(Shaoxing Hospital,Zhejiang University School of Medicine),Shaoxing 312000,Zhejiang,China)

机构地区：[1]绍兴市人民医院(浙江大学绍兴医院),浙江绍兴312000

出　　处：《国际流行病学传染病学杂志》2020年第1期55-59,共5页International Journal of Epidemiology and Infectious Disease

基　　金：绍兴市公益性技术应用研究项目(2015B70044)。

摘　　要：目的了解浙江绍兴市人民医院肠道外分离气单胞菌对喹诺酮类抗菌药物的耐药现状,及其主要耐药机制。方法对临床分离的50株肠道外气单胞菌菌株进行喹诺酮类药物敏感性测试,用PCR扩增喹诺酮类耐药基因gyrA、parC、qnrA、qnrB、qnrS、qepA和aac(6')-Ib-cr,基因序列比对分析该地区gyrA和parC基因的突变情况,分析肠道外气单胞菌对喹诺酮类抗菌药物的耐药表型和耐药基因的关联性。结果绍兴地区肠道外气单胞菌对萘啶酸(NA)的耐药率已高达82.0%(41/50),对环丙沙星(CIP)和左氧氟沙星(LVX)的耐药率都在50.0%左右。27株(54.0%)菌株对两种以上喹诺酮类药物耐药。qnrS和aac(6')-Ib-cr的阳性率分别为52.0%和18.0%。qnrS基因阳性菌株对NA、CIP、LXV耐药率均显著高于阴性菌株(P<0.05);aac(6′)-Ib-cr基因阳性菌株对CIP和LVX的耐药率显著高于阴性菌株(P<0.05),但对萘啶酸耐药性无明显差异。未检测出qnrA、qnrB和qepA基因。gyrA中主要存在Ser83→Ile,parC中主要存在Ser80→Ile变异。结论绍兴地区分离的肠道外气单胞菌对喹诺酮类药物表现高耐药性,染色体介导的靶位基因突变为其主要耐药机制,目前突变较单一。Objective To investigate the resistance status and main resistance mechanism to quinolones antibiotics of the extraintestinal Aeromonas spp.in Shaoxing People’s Hospital,and to provide an important basis for clinical treatment and prevention of Aeromonas infections.Methods A total of 50 extraintestinal Aeromonas strains isolated from the clinical patients were analyzed for antibiotics sensitivity of quinolones.Polymerase chain reaction(PCR)was performed to amplify quinolone resistance genes gyrA,parC,qnrA,qnrB,qnrS,qepA and aac(6')-Ib-cr,and sequencing was used to screen the mutation of gene gyrA and parC,analyzing the relationship between the resistance phenotype to quinolone and resistance-related genes of Aeromonas isolates.Results The resistance rate of the extraintestinal Aeromonas to naphthoic acid(NA)was as high as 82.0%(41/50)in Shaoxing.The resistance rates to ciprofloxacin(CIP)and levofloxacin(LVX)were also about 50.0%.Twenty-seven strain(54.0%)were resistant to more than two types of quinolones.The positive rates of qnrS and aac(6')-Ib-cr were 52.0%and 18.0%,respectively.The resistance rates of qnrS gene positive strains to NA,CIP and LVX were significantly higher than those of negative strains(P<0.05).The resistance rates of aac(6')-Ib-cr gene positive strains to CIP and LVX were significantly higher than those of negative strains(P<0.05),but there was no significant difference in resistance to naphthoic acid.No qnrA,qnrB and qepA genes were detected.The main mutation in gyrA gene was Ser83→Ile,while Ser80→Ile in parC gene.Conclusions The extraintestinal Aeromonas isolates from Shaoxing showed high resistance to quinolones.Chromosome-mediated target gene mutation is the main mechanism of drug resistance.The target gene mutation of quinolones was relatively simple,and there is no complex mutation.

关 键 词：气单胞菌属 喹诺酮类 耐药性 基因 

分 类 号：R446[医药卫生—诊断学]