儿童侵袭性鲍曼不动杆菌感染的危险因素和耐药模式分析

Risk factors and resistance patterns of invasive Acinetobacter Baumannii infection in Children

目的探讨儿童侵袭性鲍曼不动杆菌感染的相关危险因素及耐药模式。方法回顾性研究,收集2016年1月至2018年12月6家医院血流和脑脊液鲍曼不动杆菌培养阳性的98例住院患儿的基本信息、临床资料和抗菌药物敏感试验检测结果进行分析。根据感染菌株对碳青霉烯类的敏感性,分为碳青霉烯类敏感鲍曼不动杆菌(CSAB)组和碳青霉烯类耐药鲍曼不动杆菌(CRAB)组;根据感染可能的来源,分为医院感染组和社区感染组。组间比较采用χ2检验或Fisher确切概率检验、秩和检验进行分析,采用Logistic回归分析儿童侵袭性CRAB感染的危险因素。结果 98例患儿中男56例、女42例,发病年龄8(2,24)月龄,62例(63%)来自农村。87例(89%)为血液感染,12例(12%)为脑膜炎(1例同时合并血流感染)。66例(67%)接受了侵袭性操作或手术,54 例(55%)接受了含碳青霉烯类抗菌药物的治疗。CRAB组24例、CSAB组74例。CRAB组患儿起病年龄低于CSAB组[4(1,9)比10(4,24)月龄,Z=-2.16,P=0.031],CRAB组患儿在重症监护病房住院、接受碳青霉烯类抗菌药物治疗、合并肺炎及发生不良预后的比例均高于CSAB组[6例(25%)比 4例(5%)、18例(75%)比36例(49%)、17例(71%)比 17例(23%)、6例(25%)比4例(5%),χ2=5.61、5.09、18.32、5.61,均P<0.05]。医院感染组77例、社区感染组21例。医院感染组患儿在院内感染高危病房住院的比例、住院时间、接受抗菌药物治疗种类、抗菌药物治疗时间均高于社区感染组(均P<0.05)。Logistic回归分析显示农村地区居住(OR=8.42,95%CI 1.45~48.88)、先前机械通气(OR=12.62,95%CI 1.31~121.76)、先前的抗菌药物治疗(OR=4.90,95%CI 1.35~17.72)是CRAB感染的独立危险因素。CSAB菌株庆大霉素耐药率为20%(13/65),其他抗菌药物的耐药率均<6%,而CRAB分离株对氨苄西林-舒巴坦(20/20)、头孢吡肟(23/23)、派拉西林(17/17)、美罗培南(23/23)和亚胺培南(24/24)耐药率均为100%,其他抗菌药物耐药率也高达42%~96%。结论我国儿童侵袭性鲍曼不动杆菌感染多数为医院感染。侵袭性CRAB感染患儿预后更差,分离到的CRAB菌株耐药率高。农村地区居住、先前机械通气和先前抗菌药物治疗是侵袭性CRAB感染的独立危险因素。应加强院感防控和抗菌药物管理,降低鲍曼不动杆菌的感染。

Objective To understand the risk factors and antibiotics-resistant patterns of invasive Acinetobacter baumannii infection in Children.Methods This retrospective study was conducted in 6 tertiary hospitals from January 2016 to December 2018.The basic information,clinical data and the results of antimicrobial susceptibility testing were collected from the 98 pediatric inpatients with Acinetobacter baumannii isolated from blood or cerebrospinal fluid and analyzed.According to the susceptibility of the infected strains to carbapenems,they were divided into carbapenem-sensitive Acinetobacter baumannii(CSAB)group and carbapenem-resistant Acinetobacter baumannii(CRAB)group.According to the possible sources of infection,they were divided into nosocomial infection group and community infection group.Chi-square test or Fisher exact test were used to analyze categorical variables and rank sum test were used to analyze continuous variables.The risk factors of invasive CRAB infection in children were analyzed by Logistic regression.Result There were 56 males and 42 females in 98 cases.The onset age of patients was 8(2,24)months.There were 62 cases(63%)from rural area.A total of 87 cases(89%)were confirmed with bloodstream infection,and 12 cases(12%)confirmed with meningitis(1 case was accompanied with bloodstream infection).In these patients,66 cases(67%)received invasive medical procedures or surgery,54 cases(55%)received carbapenems-containing therapy.Twenty-four cases were infected with CRAB,and 74 cases with CSAB.The onset age of cases in CRAB group was lower than that in CSAB group(4(1,9)vs.10(4,24)months,Z=-2.16,P=0.031).The proportions of hospitalization in intensive care unit,carbapenem antibiotics using,pneumonia and adverse prognosis in CRAB group were higher than those in CSAB group(6 cases(25%)vs.4 cases(5%),18 cases(75%)vs.36 cases(49%),17 cases(71%)vs.17 cases(23%),6 cases(25%)vs.4 cases(5%),χ2=5.61,5.09,18.32,5.61,all P<0.05).Seventy-seven cases were nosocomial infection and 21 cases were hospital-acquired infection.The proportion of children hospitalized in high-risk wards for nosocomial infections,length of hospitalization,number of antimicrobial therapy received and duration of antimicrobial therapy were higher in the hospital associated infection group than those in the community acquired infection group(all P<0.05).Logistic regression analysis showed that children from rural area(OR=8.42,95%CI 1.45-48.88),prior mechanical ventilation(OR=12.62,95%CI 1.31-121.76),and prior antibiotic therapy(OR=4.90,95%CI 1.35-17.72)were independent risk factors for CRAB infection.The resistance percentage of CSAB isolates to many classes of antibiotics was<6%except to gentamicin,which was as high as 20%(13/65).All CRAB isolates of resistant to ampicillin-sulbactam(20/20),cefepime(23/23),piperacillin(17/17),meropenem(23/23)and imipenem(24/24)were 100%.The resistance percentage to other antibiotics were up to 42%-96%.Conclusions Most of invasive Acinetobacter baumannii infection in children in China are hospital-acquired.The outcome of invasive CRAB infection was poorer than that of CSAB infection.The drug resistance rate of CRAB strains isolated is high.Living in rural area,prior invasive mechanical ventilation and prior antibiotic therapy were independent risk factors for invasive CRAB infection.The prevention and control of nosocomial infection and appropriate use of antibiotics to reduce Acinetobacter baumannii infection.