耐碳青霉烯类肺炎克雷伯菌的耐药性及同源性研究
发布时间：2018-09-07 06:41
【摘要】：研究背景肺炎克雷伯菌是革兰阴性兼性厌氧杆菌,是临床细菌分离培养最为常见的条件致病菌之一。但是由于广谱青霉素类、第三代头孢菌素、单环类、β-内酰胺酶抑制剂的复合制剂及喹诺酮类等广谱抗生素在临床治疗肺炎克雷伯菌感染患者中的大量使用,肺炎克雷伯菌能够产生超广谱内酰胺酶(ESBLs)和头孢菌素酶(AmpC酶)等从而对广谱类抗生素表现出多重耐药性。碳青霉烯类是β-内酰胺类,是临床治疗ESBLs及AmpC酶等肠杆菌科细菌感染患者的一类广谱抗生素。然而,伴随着碳青霉烯类抗生素在临床大量的使用,对碳青霉烯类抗生素耐药的肠杆菌科以及不动杆菌属也在逐渐上升,给临床治疗带来了严峻挑战。其中,耐碳青霉烯类抗生素的主要机制就是细菌产生碳青霉烯酶。碳青霉烯酶是指能够水解青霉素类、头孢菌素类、碳青霉烯类以及β-内酰胺酶抑制剂、氨基糖苷类、喹诺酮类等多种抗菌药物的一大类β-内酰胺酶,能大大降低药物的作用效果甚至消失。碳青霉烯酶大都由质粒介导,具有广泛的传播性。本研究对广州军区广州总医院收集的53株耐碳青霉烯类肺炎克雷伯菌(CRKP)进行了菌种鉴定以及药敏试验,并对其耐药谱以及耐药表型进行了研究,检测碳青霉烯酶基因以及进行了脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST),并且制定了调查表进行临床病例资料收集以及整理。为我院临床抗生素的合理使用及采取防治措施提供信息参考。研究方法收集2015年7月到2016年7月自51名患者分离出53株CRKP;VITEK-2全自动微生物仪器以及MALDI-TOF MS对CRKP进行鉴定及药敏试验,并同时使用K-B法以及E-test法进行确认;采用改良Hodge试验(MHT)和EDTA试验进行碳青霉烯酶表型实验;PCR检测常见碳青霉烯酶基因KPC、VIM、IMP、NDM-1、OXA-48基因,并进行测序以及亚型的确定;PFGE和PLST两种技术进行同源性研究。研究结果53株菌株均为碳青霉烯类耐药;MHT 52株阳性,EDTA均为阴性;52株CRKP携带KPC-2,仅有1株细菌携带IMP-4,未发现VIM、NDM-1、OXA-48基因;经PFGE分为Ⅰ型、Ⅱ型、Ⅲ型、Ⅳ型4种不同类型;PFGE的Ⅰ型、Ⅱ型和Ⅲ型耐碳青霉烯类肺炎克雷伯菌株属于ST11;16号为Ⅳ型属于ST16;本次研究VITEK MS鉴定出来的CRKP包括粘液型在内菌株鉴定分值Vitek≥90%,结果高度可信且与MLST分型的结果高度相符。结论本次研究,53株耐碳青霉烯类肺炎克雷伯菌主要耐药机制是携带KPC-2,存在克隆感染,表明医院得加强感染控制;PFGE的Ⅰ型、Ⅱ型为主要流行菌株并且在ICU以及MICU两大科室克隆传播,且53株CRKP存在着高度的亲缘关系;ST11作为本院耐碳青霉烯类肺炎克雷伯菌的主要菌株。
[Abstract]:Background Klebsiella pneumoniae is a Gram-negative facultative anaerobic bacterium and one of the most common opportunistic pathogens in clinical bacteria isolation and culture. However, broad-spectrum antibiotics such as broad-spectrum penicillin, third-generation cephalosporins, monocyclic compounds, 尾 -lactamases inhibitors and quinolones are widely used in clinical treatment of Klebsiella pneumoniae infection. Klebsiella pneumoniae can produce extended-spectrum lactamases (ESBLs) and cephalosporinase (AmpC), thus showing multidrug resistance to broad-spectrum antibiotics. Carbapenems are 尾-lactams, which are a kind of broad-spectrum antibiotics for clinical treatment of enterobacteriaceae infections such as ESBLs and AmpC enzymes. However, with the widespread use of carbapenem antibiotics in clinical practice, enterobacteriaceae and Acinetobacter, which are resistant to carbapenem antibiotics, have gradually increased, which has brought severe challenges to clinical treatment. The main mechanism of carbapenem resistance is that bacteria produce carbapenem. Carbapenem is a class of 尾 -lactamases capable of hydrolyzing penicillin, cephalosporins, carbapenes and 尾 -lactamases inhibitors, aminoglycosides, quinolones, etc. Can greatly reduce the effect of drugs or even disappear. Carbapenem is widely transmitted by plasmid. In this study, 53 strains of Klebsiella carbapenicilli (CRKP) collected from Guangzhou General Hospital of Guangzhou military region were identified and tested for drug sensitivity, and the drug resistance spectrum and phenotype were studied. Detection of carbapenase gene, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST),) were carried out, and a questionnaire was developed for clinical case data collection and collation. To provide information reference for rational use of antibiotics and preventive measures in our hospital. Methods from July 2015 to July 2016, 53 strains of CRKP;VITEK-2 were isolated from 51 patients, and MALDI-TOF MS was used to identify CRKP and drug sensitivity test. K-B method and E-test method were used to confirm CRKP. The modified Hodge test (MHT) and EDTA test were used to detect the KPC,VIM,IMP,NDM-1,OXA-48 gene of common carbapenase gene. The homology was studied by sequencing and subtype determination. The results showed that all 53 strains of carbapenem resistant MHT52 were positive for EDTA. Only one strain of CRKP carrying KPC-2, had no VIM,NDM-1,OXA-48 gene, and was classified into four types by PFGE: type 鈪，
本文编号：2227495
[Abstract]:Background Klebsiella pneumoniae is a Gram-negative facultative anaerobic bacterium and one of the most common opportunistic pathogens in clinical bacteria isolation and culture. However, broad-spectrum antibiotics such as broad-spectrum penicillin, third-generation cephalosporins, monocyclic compounds, 尾 -lactamases inhibitors and quinolones are widely used in clinical treatment of Klebsiella pneumoniae infection. Klebsiella pneumoniae can produce extended-spectrum lactamases (ESBLs) and cephalosporinase (AmpC), thus showing multidrug resistance to broad-spectrum antibiotics. Carbapenems are 尾-lactams, which are a kind of broad-spectrum antibiotics for clinical treatment of enterobacteriaceae infections such as ESBLs and AmpC enzymes. However, with the widespread use of carbapenem antibiotics in clinical practice, enterobacteriaceae and Acinetobacter, which are resistant to carbapenem antibiotics, have gradually increased, which has brought severe challenges to clinical treatment. The main mechanism of carbapenem resistance is that bacteria produce carbapenem. Carbapenem is a class of 尾 -lactamases capable of hydrolyzing penicillin, cephalosporins, carbapenes and 尾 -lactamases inhibitors, aminoglycosides, quinolones, etc. Can greatly reduce the effect of drugs or even disappear. Carbapenem is widely transmitted by plasmid. In this study, 53 strains of Klebsiella carbapenicilli (CRKP) collected from Guangzhou General Hospital of Guangzhou military region were identified and tested for drug sensitivity, and the drug resistance spectrum and phenotype were studied. Detection of carbapenase gene, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST),) were carried out, and a questionnaire was developed for clinical case data collection and collation. To provide information reference for rational use of antibiotics and preventive measures in our hospital. Methods from July 2015 to July 2016, 53 strains of CRKP;VITEK-2 were isolated from 51 patients, and MALDI-TOF MS was used to identify CRKP and drug sensitivity test. K-B method and E-test method were used to confirm CRKP. The modified Hodge test (MHT) and EDTA test were used to detect the KPC,VIM,IMP,NDM-1,OXA-48 gene of common carbapenase gene. The homology was studied by sequencing and subtype determination. The results showed that all 53 strains of carbapenem resistant MHT52 were positive for EDTA. Only one strain of CRKP carrying KPC-2, had no VIM,NDM-1,OXA-48 gene, and was classified into four types by PFGE: type 鈪，
本文编号：2227495
本文链接：https://www.wllwen.com/linchuangyixuelunwen/2227495.html
最近更新
教材专著
