江西省新生儿筛查CRKP定植菌株分子流行病学特征

Molecular epidemiological characteristics of colonized CRKP strains in neonates of Jiangxi Province

目的探究新生儿耐碳青霉烯类肺炎克雷伯菌(CRKP)定植株分子流行病学特征。方法对2021年1月1日-12月31日江西省5家医院收治的新生儿患者开展耐碳青霉烯类肠杆菌科细菌(CRE)显色培养基主动筛查,将鉴定为肺炎克雷伯菌(KP)新生儿纳入研究对象,根据碳青霉烯类是否耐药分为CRKP和碳青霉烯敏感KP(CSKP)两组;调查CRKP和CSKP两组新生儿临床特征(包括性别、年龄、发热、入院诊断、炎性指标、抗菌药物应用、抗菌药物使用是否超过7天等),对CRKP与CSKP新生儿临床特征进行对比;同时对CRKP耐药基因进行酶型检测,分析CRKP不同耐药基因的构成情况;对所有CRKP和部分CSKP进行多位点序列分型(MLST)。结果5家医院共筛出CRE阳性标本168份,经质谱仪和纸片法鉴定KP 82株,其中CRKP 25株、CSKP 57株;CRKP新生儿平均日龄(11.64±10.86)d;对比CRKP与CSKP新生儿临床特征,抗菌药物使用时长超过7天能增加CRKP检出率;25株CRKP中产NDM酶14株,产丝氨酸酶1株,不产酶10株,从MLST分型来看,CRKP以ST1564和ST37最为常见(各占20.00%),ST2601和ST11则次之(各占16.00%)。结论新生儿住院患儿CRKP定植率较高,CRKP耐药基因以金属酶、ST1564和ST37最为常见,应加强新生儿CRKP监测和感染防控。

OBJECTIVE To explore the molecular epidemiological characteristics of carbapenem resistant Klebsiella pneumoniae(CRKP)colonization in newborns.METHODS From Jan.1 to Dec.31,2021,active screening of carbapenem resistant Enterobacteriaceae(CRE)chromogenic medium was carried out on neonatal patients admitted to 5 hospitals in Jiangxi region,and neonates identified as Klebsiella pneumoniae(KP)were included in the study,and were divided into CRKP and carbapenem-sensitive K.pneumoniae(CSKP)groups according to whether carbapenem resistant was present.The clinical characteristics(including gender,age,fever,admission diagnosis,inflammatory indicators,antibiotic use,and whether antibiotic were used for more than 7 days)of newborns in the CRKP and CSKP groups were investigated,and the clinical characteristics of newborns with CRKP were compared with those of newborns with CSKP.At the same time,enzyme-type assay for CRKP-resistance genes was carried out to analyze the composition of different CRKP resistance genes;and the multilocus sequence typing(MLST)was performed on all CRKPs and some CSKPs.RESULTS A total of 168 CRE positive specimens were screened from 5 hospitals,and 82 KP strains were identified by mass spectrometry and paper disc method,including 25 CRKP strains and 57 CSKP strains.The average daily age of CRKP newborns was(11.64±10.86)days.Comparing the clinical characteristics of newborns with CRKP and CSKP,the duration of antibiotics use for more than 7 days could increase CRKP detection rate.Among the 25 CRKPs,14 strains were NDM enzymes-producing,1 strain was serine enzyme-producing,and 10 strains were non-enzymatic.In terms of the MLST typing,ST1564 and ST37 were the most common CRKPs(20.00%of each),followed by ST2601 and ST11(16.00%of each).CONCLUSIONS The rate of CRKP colonization was high in neonatally hospitalized children,and CRKP resistance genes were most found in metalloenzymes,ST1564,and ST37.Therefore,neonatal CRKP survellance and infection prevention and control should be strengthened.