Genotype Analysis And Pathway Investigation Of Carbapenem-Resistant Klebsiella Pneumoniae

Objective: Nosocomial infections caused by carbapenem-resistant Klebsiella pneumoniae(CRKP)caused widespread concern due to its high transmission rate,high mortality,and high drug resistance.In recent years,the number of patients with CRKP infection in the hospital has gradually increased,and the situation of bacterial resistance is more severe.In order to prevent the spread of CRKP in hospitals,to understand the genotypes of CRKP infections in hospitals,their evolutionary relationships,and the relationship between the transmission paths of CRKP patients,to provide data support for hospital infection prevention and control.Methods: Twenty-one CRKP non-repeating strains were collected from the hospital from November 2018 to March 2019.The strains were identified using the Merrier VITEK microbiological identification instrument,and the minimum inhibitory concentration MIC method and KB method were used to analyze the antibacterial activity of the strains.Drug sensitivity,mCIM combined with eCIM test to detect carbapenemase phenotype.Extract the DNA of CRKP strains,use the Illumina Hiseq2500 platform for whole genome sequencing,SPAdes software for sequence splicing,Staramr software for analysis of strain resistance genes,MLST software for multilocus sequence typing(MST),and Ridom SeqSphere + software for Core genome multilocus sequence typing(cgMLST)and construction of a minimum spanning tree(MST).SCOTTI software was used to construct a transmission path relationship map based on the extracted strain core genes,the time of collection of CPKP specimens,and the time of patient discharge.Results: The 21 strains of CRKP all carried blaKPC-2 resistance genes,and the MLST typing was ST11,while the cgMLST typing showed that CT3176(14 strains,66.7%)was the dominant epidemic strain in the hospital,and the others were CT1689(3strains),CT1313 type(2 strains),CT1814 type(1 strain),and CT3195 type(1 strain).In the MST,CRKP in our hospital was divided into 3 large clusters,and CT3176 strainsformed the main cluster.In 19 CRKP transmission path diagrams with core genomes,42% transmission probability was analyzed between strains 7 and 29,strains 12 and 17 had a transmission probability of 37%,and the transmission probability among other strains was low.Conclusion: The 21 strains of CRKP in this hospital are multi-drug resistant to commonly used antibacterials and highly express resistance genes.In the type analysis,the 21 strains of CRKP were all ST11 type,and the CT3176 subtype was the main type and spread in a small area in the hospital.According to the diagram of the nosocomial infection transmission path,it was found that due to poor hand hygiene compliance of operators,it may lead to the spread of CRKP strains in clinical care.