T6SS阳性CRKP临床感染特征及毒力基因分析OA北大核心CSTPCD

Objective To analyze the clinical infection characteristics,detection rates of antimicrobial resistance and virulence genes,as well as biofilm formation ability of T6SS-positive carbapenem-resistant Klebsiella pneumoniae(CRKP),provide reference for clinical prevention and control of CRKP infection.Methods Clinically isolated CRKP strains and patients'data from a tertiary first-class hospital in Anhui Province from January 2019 to Decem-ber 2022 were collected.T6SS genes,virulence genes,antimicrobial resistance genes,and molecular typing were detected with polymerase chain reaction method.Biofilm formation ability was detection with 96-well plate crystal violet staining method.Results A total of 160 CRKP strains were included in study.The main sources of speci-mens were sputum(46.9％)and blood(26.3％).CRKP strains exhibited multidrug-resistant phenotype,mainly carrying blaKPC(80.6％),followed by blaNDM(17.5％).CRKP were divided into T6SS-positive group(n=129,80.6％)and T6SS-negative group(n=31,19.4％)based on whether they carried T6SS.The proportion of pa-tients with chronic pulmonary and heart diseases in T6SS-positive group was higher than that in T6SS-negative group(P＜0.05),and the prognosis was worse than negative group(P＜0.05).In T6SS-positive group,the de-tection rates of iucA,mrkD,rmpA2,peg344,wabG,and fimH were all higher than those in T6SS-negative group(all P＜0.05).The main type in CRKP was ST11(68.8％),withK64-ST11 accounting for 70.9％andK47-ST11 accounting for 25.5％.The proportions of ST11 CRKP and K64-ST11 CRKP in T6SS-positive group were both higher than T6SS-negative group(both P＜0.05).Biofilm formation ability of CRKP in T6SS-positive group was stronger than T6SS-negative group(P＜0.001).Except blaOXA-48 gene,there was no statistical difference in carrying of other carbapenem resistance genes and antimicrobial resistance rates between the two groups.Conclusion CRKP in this area exhibits multidrug resistance,with a higher detection rate of T6SS.T6SS-positive CRKP has a higher de-tection rate of virulence genes and stronger biofilm formation ability.