Risk Factors And Molecular Epidemiology Of Infections Caused By Extended-spectrum Beta-lactamases-producing Klebsiella Pneumonia

ObjectivesThe aim of this study is to invegaste the antibiotic resistance and clinical characteristics of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae(ESBL-KP)that isolated from patients who were admitted to hospital in Xiamen;discuss the main risk factors of infection caused by ESBL-KP;investigate the molecular epidemiology of ESBL-KP,determine the main genotype and resistant genes of the ESBL-KP.Methods1.Klebsiella pneumoniae isolates were collected from inpatients in January 2014 to August 2015.The susceptibility of 23 antibiotics was determined by Kirby-Bauer method.Compare ESBLs positive and negative Klebsiella pneumoniae in antibiotic resistance and clinical characteristics2.The retrospective study was used to investigate risk factors of infection caused by ESBL-KP.The clinical data of inpatients who had the hospital-acquired infection from January 2014 to August 2015.Univariate analysis and multiple logistic regression analysis were used.3.The sequence types of 40 ESBL-KP strains were determined by Multiple Locus Sequence Typing.Analysis main sequence of ESBL-KP and the distribution of departments.Analysis phylogenetic of relationships was using Neighbor-Joining method.4.The SHV、TEM、CTX-M were detected by Polymerase Chain Reaction.Analysis resistant genes of ESBL-KP.Result1.927 Klebsiella pneumoniae strains were collected from January 2014 to August 2015 including 275 ESBL-KP strains,the rate of ESBLs strains was 29.67%.The clinical characteristics showed that the sputum specimens were at most and the patients who were older than age 70 were at most.Mainly in the ICU,Neurosurgery ward,Liver surgical ward and traditional Chinese medicine department.2.23 kinds of antibiotics have different levels of resistance for Kpn.The rate of ampicillin resistance was the most high in the 275 ESBL-KP strains followed by cephalosporin antibiotics,but the susceptibility rates of ESBL-KP to imipenem and meropenem were more than 90.0%.ESBLs negative strains were sensitive for many antibiotics except ampicillin.The resistance rates of aminoglycoside,quinolone class,carbapenem,cephalosporins,and penicillins in ESBL-KP were significantly higher than non-ESBLs strains(p<0.001).3.The use of cephalosporins antibiotics and quinolone were independent risk factors for infection caused by ESBL-KP.4.ST23 and ST37 were the most sequence types;there new sequence types were found.The most resistance gene was blaSHV,meanwhile some strains carried two or three resistance genes.Conclusions1.The antibiotics resistance rates of Klebsiella pneumoniae the positive rate of ESBL are high in the hospital in Xiamen.These indicate that we should pay more attention to the monitoring of bacterial drug resistance.2.The main sequence types are ST23 and ST37,the main resistance gene is SHV.No the outbreak of nosocomial infection is found,this suggest that the measures of controlling nosocomial infection are generally better.3.Using of cephalosporins antibiotics and quinolone should be rational clinically to reduce the emergence of resistant strains.