70岁以上长期住院患者碳青霉烯耐药肠杆菌科细菌的定植情况分析

Study on the colonization of Carbapenem resistant Enterobacteriaceae in long-term hospitalized patients over 70 years old

目的:分析70岁以上长期住院老年患者碳青霉烯耐药肠杆菌科细菌(CRE)定植情况。方法:选取2021年1月—5月在上海市金山区众仁老年护理医院住院时间超过1个月、年龄超过70岁的220例老年患者,使用CRE筛选平板筛选大便中的CRE菌株,采用碳青霉烯酶抑制增强实验检测CRE菌株耐药基因表型,采用PCR的方法检测耐药基因(KPC、NDM、IMP、VIM、OXA-48、OmpC),使用软件WHOnet5.6和SAS9.4进行数据的分析。结果:220例老年患者大便标本中,CRE的定植率为6.81%,主要的菌株为大肠埃希菌。CRE菌株基因表型结果表达A类酶的为5株,表达B类酶的为9株,其中有1株同时表达A类和B类;基因检测的结果显示,7株含有NDM基因,4株含有KPC基因,1株含有IMP基因,1株同时含有KPC和VIM基因型,未发现含有OXA-48和OmpC基因型的菌株。三种菌均未发现对妥布霉素和环丙沙星耐药的菌株;大肠埃希菌对氨曲南的耐药率仅为11.11%,对庆大霉素和头孢吡肟的耐药率为33.33%;未发现对复方新诺明耐药的肺炎克雷伯菌。结论:70岁以上长期住院老年患者的肠道定植的CRE菌株在耐药表型上存在一定特点,70岁以上长期住院老年患者的CRE临床感染率较高,其中主要的菌株为大肠埃希菌,可根据抗生素药物敏感结果,结合实际情况选择肠道CRE菌株的去定植。

Objective To analyze the colonization of Carbapenem resistant Enterobacteriaceae in elderly patients over 70 years old,in order to provide basis for clinical treatment and prevention.Methods 220 elderly patients over 70 years old who were hospitalized in our hospital for more than one month from January to May 2021 were randomly selected as subjects.CRE screening plate was used to screen CRE strains in stool.Carbapenem inhibition enhancement test was used to detect the drug resistance gene phenotype of CRE strains.The drug resistance genes(KPC,NDM,imp,VIM,oxa-48,OmpC)were detected by PCR.The data were analyzed by software whonet 5.6 and sas 9.4.Results The colonization rate of CRE strain in stool samples was 6.81%,and the main strain was Escherichia coli(9/15).The gene phenotype of CRE strain showed that 5 strains expressed class a enzyme and 9 strains expressed class B enzyme,of which 1 strain expressed both class A and class B;The results of gene detection showed that 7 strains contained NDM gene,4 strains contained KPC gene,1 strain contained imp gene,1 strain contained both KPC and VIM genotypes,and no strains containing oxa-48 and OmpC genotypes were found.None of the three strains showed resistance to tobramycin and ciprofloxacin;The resistance rate of Escherichia coli to aztreonam was only 11.11%,and to gentamicin and cefepime was 33.33%;No Klebsiella pneumoniae resistant to cotrimoxazole was found.Conclusion The CRE strains colonized in the intestines of elderly patients over 70 years old have their own characteristics in drug resistance phenotype.According to the results of antibiotic susceptibility,the colonization of intestinal CRE strains should be selected in combination with the actual situation.