Analysis of susceptibility factors and the relationship between drug resistance phenotype and gene of multi-drug resistant Klebsiella pneumoniae in ICU

SHU Meilin; YANG Mei; RAO Chenglong; DAI Hongying; DENG Linlin

doi:10.3969/j.issn.1007-8134.2023.06.012

Abstract：Objective To analyze the susceptibility factors of multi-drug resistant Klebsiella pneumoniae(KP)in intensive care unit(ICU)and the relationship between drug resistance phenotype and gene,so as to provide a basis for clinical development of comprehensive prevention and treatment measures.Methods A total of 180 patients with KP infection admitted to the ICU ward of Yuechi County People's Hospital from January 2021 to January 2023 were selected as the research objects.According to the drug sensitivity results,they were divided into non-multi-drug resistant group(n=100)and multi-drug resistant group(n=80).Drug resistance phenotypes and susceptibility factors were compared between the two groups.Multivariate Logistic regression was used to analyze the risk factors of multidrug-resistant KP in ICU.A nomogram model was established to analyze the genomic characteristics of KP and related virulence factors.Results The KP gene sequencing results of the multidrug-resistant group showed that the most abundant plasmid replicators were the Col and Inc families.The significantly highly expressed genes identified in the multidrug resistance group were serum resistance factors determining the O-antigen lipopolysaccharide serotype,and the types of polysaccharide capsules(K antigen)were determined by immune evasion factors,capsule synthesis regulation,efflux pump expression and enterobacilicin,which were also closely related to KP infection mode and nosocomial infection.The length of ICU stay,mode of mechanical ventilation,duration of mechanical ventilation,history of carbapenem use,duration of carbapenem use,history of blood transfusion,history of parenteral nutrition,history of sputum suction,and history of vascular catheter use in the multi-drug resistant group were higher than those in the non-multi-drug resistant group(P＜0.05).ICU length of stay≥19 d,mechanical ventilation≥7 d,use of invasive mechanical ventilation,history of carbapenem use,duration of carbapenem use≥7 d,and history of sputum suction were independent risk factors affecting the susceptibility of multidrug-resistant KP in ICU patients.The results of the nomogram model established based on the risk factors suggested that patients with the above risk factors had a higher risk of susceptibility to multidrug-resistant KP in ICU.The internal validation results of the model showed that the calibration curves before and after verification were well fitted to the ideal curve.Conclusions Multidrug-resistant KP infection in ICU is strongly associated with prolonged hospitalization,mechanical ventilation,carbapenem use,sputum aspiration history,specific gene expression,and plasmid replicator types,which collectively increase the risk of infection in patients.