耐碳青霉烯类肠杆菌目细菌易感因素及其碳青霉烯酶表型分析

Susceptibility factors of carbapenem resistant Enterobacterales and analysis of carbapenemase phenotype

目的研究耐碳青霉烯类肠杆菌目细菌(carbapenem-resistant Enterobacterales,CRE)的易感因素及分析其耐碳青霉烯酶表型。方法收集CRE 114株,选择同期碳青霉烯类药物敏感肠杆菌目细菌(carbapenem-sensitive Enterobacterales,CSE)110株为对照组,分析各菌株采集对象的临床资料,采用Logistic回归分析法分析患者感染CRE的影响因素。采用改良碳青霉烯类失活法(modified carbapenem inactivation method,mCIM)联合乙二胺四乙酸碳青霉烯类失活法(ethylenediaminetetraacetic acid-modified carbapenem inactivation method,eCIM)试验分析其碳青霉烯酶表型,用酶抑制剂增强试验补充。结果Logistic回归分析结果显示,住院时间大于30天(OR=29.357)、患有糖尿病(OR=7.203)、使用碳青霉烯类药物(OR=96.072)、入住ICU(OR=28.062)、使用β内酰胺酶复合制剂(OR=4.160)是CRE感染的危险因素(P<0.05),联合使用抗生素(OR=0.085)是CRE感染的保护因素(P<0.05)。mCIM试验与eCIM试验结果显示,114株CRE菌株中产丝氨酸碳青霉烯酶90株、产金属碳青霉烯酶24株。酶抑制剂增强实验结果显示,114株CRE菌株中产丝氨酸碳青霉烯酶90株、产金属碳青霉烯酶20株,既产丝氨酸碳青霉烯酶又产金属碳青霉烯酶4株。结论长时间住院、入住ICU、使用碳青霉烯类药物和β内酰胺酶复合制剂、糖尿病可导致患者更容易被CRE感染;开展耐药表型分析,可指导临床合理使用抗菌药物。

Objective To study susceptibility factors of carbapenem-resistant Enterobacterales(CRE)and its phenotype of carbapenemase.Methods A total of 114 strains of CRE were collected as the study group,and 110 strains of carbapenem-sensitive Enterobacterales(CSE)were selected as the control group.The clinical data of each strain was analyzed.Logistic regression analysis was used to analyze the influencing factors of CRE infection.The phenotype of carbapenemase was analyzed by modified carbapenem inactivation method(mCIM)combined with ethylenediaminetetraacetic acid-modified carbapenem inactivation method(eCIM),supplemented by enzyme inhibitor enhancement test.Results Logistic regression analysis showed that hospitalization time greater than 30 days(OR=29.357),diabetes mellitus(OR=7.203),use of carbapenem(OR=96.072),admission to ICU(OR=28.062),and use of β Lactamase complex(OR=4.160)were risk factors for CRE infection(P<0.05),and combination of antibiotics(OR=0.085)was a protective factor for CRE infection(P<0.05).The results of mCIM test and eCIM test indicated that 114 CRE strains contained 90 strains of serine carbapenemase and 24 strains of metal carbapenemase.The enzyme inhibitor enhancement test showed that 114 CRE strains contained 90 strains of serine carbapenemase,20 strains of metal carbapenemase,and four strains of serine-metal carbapenemase.Conclusions Prolonged hospitalization,admission to ICU,use of carbapenems andβLactamase complex,and diabetes mellitus can cause patients to be more susceptible to CRE infection.The analysis of drug resistance phenotype can guide the rational use of antibiotics in clinical practice.