151株耐碳青霉烯类肺炎克雷伯菌临床分离株毒力基因和耐药性

Virulence genes and drug resistance of 151 strains of clinical carbapenem-resistant Klebsiella pneumoniae isolates

目的探讨151株耐碳青霉烯类肺炎克雷伯菌(CRKP)临床分离株毒力基因和耐药性。方法收集2023年1月-2023年9月上海复旦大学附属华山医院151例急诊住院患者中分离的151株肺炎克雷伯菌,通过对种类识别及耐药性实验筛选,运用聚合酶链式反应(PCR)技术对CRKP毒力基因进行分析,以多基因位点-序贯分型技术(MLST)对肺炎克雷伯菌进行分子分型并对其临床特征进行分析。结果CRKP以急诊重症监护病房(ICU)临床病区为主,对常见抗菌药物有较强的耐药性,对氨苄青霉素,头孢曲松,哌拉西林/舒巴坦的耐药率均达到100.00%,CRKP和高毒力肺炎克雷伯菌(HvKP)对氨苄西林、庆大霉素、头孢唑林、磺胺甲噁唑/甲氧苄啶的抗性比较无统计学差异;CRKP对头孢曲松﹑哌拉西林/舒巴坦钠﹑头孢哌酮/舒巴坦钠、阿米卡星、环丙沙星、左氧氟沙星、氨曲南、替加环素和多黏菌素的耐药性高于HvKP(P<0.05);检测CRKP碳青霉烯酶基因携带情况,其中KPC的携带率为90.48%。包含有多个毒力基因,如maga、alls、iuta、rmpa、kfu和ytbs等。结论CRKP菌株具有耐药性和复杂的毒力机制,常携带有多种毒力基因。这种高耐药性和多毒力性的菌株在临床中对治疗构成了重大挑战,也为医院感染控制部门提供重要的参考信息,以严格防范菌株的传播。

OBJECTIVE To explore the virulence genes and drug resistance of the 151 strains of clinical carbapenem-resistant Klebsiella pneumoniae(CRKP)isolates.METHODS Totally 151 strains of K.pneumoniae were isolated from 151 emergency hospitalized patients of Huashan Hospital of Fudan University between Jan.2023 and Sep.2023.The types of KPN were identified,the drug resistance was screened by testing,and the virulence genes in the CRKP strains were analyzed by means of polymerase chain reaction(PCR).Molecular typing was carried out for the K.pneumoniae strains by multilocus sequence typing(MLST)technique,and the drug resistance of the strains were analyzed.RESULTS Among the CRKP strains isolated from the clinical wards,the majority were isolated from intensive care unit(ICU).The strains were highly resistant to the commonly used antibiotics,and drug resistance rates to ampicillin,ceftriaxone and piperacillin-sulbactam were up to 100.00%.There were no significant differences in the resistance rates to ampicillin,gentamycin,cefazolin and sulfamethoxazole-trimethoprim between CRKP strains and Hypervirulent K.pneumoniae(HvKP)strains.The drug resistance rates of the CRKP strains to ceftriaxone,piperacillin-sulbactam,cefoperazone-sulbactam,amikacin,ciprofloxacin,levofloxacin,aztreonam,tigecycline and polymyxin were significantly higher than those of the HvKP strains(P<0.05).The carrying rates of carbapenemases genes in the CRKP strains were detected,and the carrying rate of KPC was 90.48%.Some of virulence genes such as maga,alls,iuta,rmpa,kfu and ytbs were included.CONCLUSIONS The CRKP strains are drug-resistant and show complex virulence mechanisms,the strains carry with a variety of virulence genes.The high drug resistance and multiple toxicities of the strains bring great challenge to the clinical treatment and provide important information for nosocomial infection control department so as to prevent the transmission of the strains.