Resistance And Homology Study Of Carbapenems-resistant Klebsiella Pneumonia

BACKGROUNDKlebsiella pneumoniae is a gram-negative facultative anaerobic bacteria,is the clinical bacteria isolated and cultured one of the most common conditions of pathogens.However,due to the extensive use of broad-spectrum antibiotics such as broad-spectrum penicillins,third-generation cephalosporins,monocyclic,β-lactamase inhibitors and quinolones and other broad-spectrum antibiotics in the clinical treatment of patients with Klebsiella pneumoniae infection,Klebsiella pneumoniae can produce extended spectrum lactamases(ESBLs)and cephalosporins(AmpC enzymes)and so on to broad-spectrum antibiotics showed multiple drug resistance.Carbapenems are β-lactam,is the clinical treatment of ESBLs and AmpC enzymes such as Enterobacteriaceae bacterial infection in a class of broad-spectrum antibiotics.However,with the use of carbapenem antibiotics in a large number of clinical use,carbapenem antibiotics resistant Enterobacteriaceae and Acinetobacter are also gradually increased,which has brought serious challenges.Among them,the main mechanism of carbapenem antibiotics is that bacteria produce carbapenemase.Carbapenemase is a class of P-lactam which can hydrolyze penicillins,cephalosporins,carbapenems,and β-lactamase inhibitors,aminoglycosides,quinolones and the like Enzymes,can greatly reduce the effect of drugs or even disappear,mediated by the plasmid,which has a wide range of communication.In this study,53 strains of carbapenem-resistant Klebsiella pneumoniae(CRKP)collected from Guangzhou General Hospital of Guangzhou Military Region were for identification of bacteria and drug susceptibility test.The drug resistance spectrum and drug resistance phenotype were studied.Detection of carbapenemase gene and pulsed field gel electrophoresis(PFGE)and multiple site sequence typing(MLST),and the development of a questionnaire for clinical case data collection and collation.For our hospital clinical antibiotics and the rational use of preventive measures to provide information reference.METHODSFifty-three CRKP isolates were isolated from 51 different patients from July 2015 to July 2016.CRKP was identified and tested by VITEK-2 automatic microbiological instrument and MALDI-TOF MS,and at the same time PCR was performed by KB method and E-test method.The carbapenem enzyme phenotype was screened by modified Hodge test(MHT)and EDTA test.PCR was used to detect the common carbapenemase gene KPC,VIM,IMP,NDM-1,OXA-48 gene,and sequencing and subtype determination.Two studies of PFGE and PLST homology.RESULTSThe results showed that 53 strains were resistant to carbapenems.MHT 52 strains were positive and EDTA was positive.52 strains of CRKP carry KPC-2,and only one bacterium carried IMP-4.No VIM,NDM-1,OXA-48 gene.PFGE is divided into type Ⅰ,type Ⅱ,Ⅲ type,Ⅳ type 4 different types.PFGE type Ⅰ,Ⅱ and Ⅲtype carbapenem pneumonia Klebsiella strains belong to ST11.The type of CRKP identified by VITEK MS in this study included the viscera-type strain,Vitek>90%,and the results were highly reliable and highly consistent with the MLST classification.CONCLUSIONThe main resistance mechanism of 53 strains of carbapenem-resistant Klebsiella pneumoniae was to carry KPC-2,which indicated that the hospital had to strengthen the infection control measures.PFGE type I and II were the main epidemic strains and ICU and MICU,and 53 CRKPs were highly homologous.ST11 was the main strain of carbapenem-resistant Klebsiella pneumoniae.