摘要目的:调查耐碳青霉烯类肠杆菌科细菌(carbapenem-resistant enterobacteriaceae，CRE)在儿童肝移植患儿中的定植与感染率，分析CRE感染的预后及高危因素。方法:纳入天津市第一中心医院于2017年8月1日至2018年1月31日接受肝移植术的患儿共152例，其中男65例，女87例，平均年龄为7个月；37例为器官捐献全肝移植，113例为活体左外叶肝移植，2例为辅助性肝移植。收集包括术前一般情况、手术情况、术后并发症等资料；在患儿进入ICU以及转出ICU的时刻留取肛拭子细菌培养，筛查是否存在肠道CRE定植，以术后是否出现CRE感染进行分组(术后CRE感染13例，无CRE感染139例)，将患儿分为感染组和非感染组。进行单因素分析及多元Logistic回归分析确定CRE感染的独立危险因素，并对两组患儿的存活率进行分析。结果:所有患儿中，术前CRE感染、术前巨细胞病毒(cytomegalovirus，CMV)感染、术前败血症的发生率在感染组明显高于非感染组，差异具有统计学意义( P<0.005)。两组患儿在术前住院时间、体内留置中心静脉导管、儿童终末期肝病模型(pediatric end-stage liver disease，PELD)评分、术前抗生素暴露以及其他感染性疾病方面差异无统计学意义( P>0.05)。感染组在术中出血量、手术时间方面显著高于非感染组，差异具有统计学意义( P<0.05)。感染组在术后ICU治疗时间、术后非计划手术发生率、术后机械通气>24 h、入ICU前CRE定植的发生率明显高于非感染组，差异具有统计学意义( P<0.05)。与CRE感染高度相关的一些指标，如术后肺炎、肠瘘的发生率、术后1个月的降钙素原(procalcitonin，PCT)水平，在感染组也明显高于非感染组，差异具有统计学意义( P<0.05)。两组患儿在移植肝血管并发症、胆道并发症、各种原因的肝功能不全等方面的差异无统计学意义( P>0.05)。两组均存在CRE肠道定植者，感染组CRE定植12例，其中入ICU前定植9例，入ICU后定植3例；非感染组CRE定植32例，定植率23.0%(32/139)，其中入ICU前定植17例，入ICU后定植15例。Logistic回归分析提示肝移植术后CRE感染的独立危险因素包括术前CRE感染、入ICU前CRE定植、术后ICU治疗时间。感染组4例死亡；非感染组3例死亡，病死率2.2%(3/139)。 结论:CRE感染进展快，预后差，病死率高。因肝移植患儿术后发生CRE感染的独立危险因素包括肝移植术前CRE感染、入ICU前CRE定植等，所以进行肛拭子CRE筛查有利于早期预警CRE感染的发生。

abstractsObjective:To explore the colonization and infection rates of carbapenems resistant enterobacteriaceae (CRE) in pediatric liver transplantation (LT) recipients and analyze the prognosis and risk factors of CRE infection.Methods:We performed a prospective cohort study of all children undergoing LT during 6-month period to define the risk factors associated with CRE infection. Anal swab bacterial cultures were performed when children entered into and discharged from intensive care unit (ICU) for screening CRE colonization. Clinical data of preoperative status and postoperative complications were collected. Liver transplant recipients were divided into CRE infection group (n=13) and non-CRE infection group (n=139). Univariate and multivariate Logistic regressions were performed to determine the independent risk factors for CRE infection and survival rates of two groups analyzed.Results:The incidence of preoperative CRE infection, preoperative cytomegalovirus (CMV) infection, preoperative sepsis, intraoperative blood loss and operative duration were significantly higher in CRE infection group than those in non-CRE infection group ( P<0.005). In CRE infection group, postoperative ICU treatment time, postoperative incidence of unplanned surgery, postoperative frequency of mechanical ventilation>24-hour and CRE colonization prior to ICU were significantly higher than those in non-CRE infection group ( P<0.05). No significant inter-group differences existed in vascular complications, biliary tract complications, acute rejection, drug-induced liver injury or hepatitis recurrence, etc. ( P>0.05). There were 12 cases of CRE colonization in CRE infection group, including prior to ICU (n=9) and within ICU (n=3). There were 32 cases (23.0%, 32/139) of CRE colonization in non-CRE infection group, including prior to ICU (n=17) and within ICU (n=15). Logistic regression analysis indicated that the independent risk factors for CRE infection included preoperative CRE infection, CRE colonization prior to ICU and postoperative ICU treatment time. There were 4 deaths in CRE infection group and 3 deaths (2.2%, 3/139) in non-CRE infection group. Conclusions:Independent risk factors for postoperative CRE infection in pediatric liver transplant recipients include preoperative CRE infection, CRE colonization prior to ICU and postoperative ICU treatment time .CRE infection progresses rapidly with a worse prognosis and higher mortality. Anal swab CRE screening is helpful for early warning of CRE infection.