MALDI-TOF MS is a rapid microbial diagnosis method developed based on MS technology, which has been widely used in clinical microbiology laboratories around the world, due to its accurate and efficient performance in microbial identification. This chapter introduces the specific applications of MALDI-TOF MS in clinical laboratories, including strain identification, antibiotic resistance mechanism tests, bacterial strain typing, and virulence marker detection. Besides, the current situation and development trends of this technique are analyzed and its application prospects are discussed.

海军大部分基层医疗单位分布在舰船、潜艇、岛礁,规模小,科室分工不明确,检验设备老旧,人员技术能力有限,信息系统不完善.通过"深蓝"医联体检验平台硬件设施、人员培养及信息系统的建设,实现海军医疗资源的共用共享,解决海军基层医疗单位医学检验条件匮乏的问题.

目的 了解耐碳青霉烯类肠杆菌科细菌(CRE)的流行状况及耐药特征,为指导临床合理用药及感控部门对多重耐药菌防控提供依据.方法 收集2015年1月至2019年12月临床分离的CRE菌株,采用仪器法(MIC法)和纸片扩散法(K?B法)对上述菌株进行药敏试验,按美国临床实验室标准化协会(CLSI)标准对结果进行判定.采用WHONET 5.6软件和SPSS 23.0统计软件进行数据统计及分析.结果 5年9973株肠杆菌科细菌中共检出CRE菌株887株(8.89％).其中以肺炎克雷伯菌为主(609株,68.66％),其次分别为大肠埃希菌(95株,10.71％)、阴沟肠杆菌复合群(90株,10.15％)、产气克雷伯菌(25株,2.82％)及奇异变形杆菌(23株,2.59％);CRE菌株主要分布在烧伤科(203株,22.89％)、急救科(160株,18.04％)及心外科(102株,11.50％)等.与50岁以下患者相比,50岁以上的患者明显增多(P<0.05).标本主要来源于痰及支气管肺泡灌洗液(338株,38.11％).药敏结果显示,CRE菌株除对哌拉西林/他唑巴坦和头孢吡肟耐药率稍低(58.1％和59.3％)外,对其余临床常用抗菌药物耐药率均>60％.结论 CRE检出率逐年上升,临床分布广泛,对临床常用抗菌药物大多呈现高耐药性,临床医护人员应通过早期筛查CRE、严格执行隔离措施、合理使用抗菌药物等手段来预防和减少CRE院内感染的发生.

目的 了解肺癌患者化疗后肺部感染病原菌的构成及其耐药性,为临床合理用药提供参考.方法 收集2015年1月—2020年12月海军军医大学第一附属医院170例化疗后发生肺部感染的肺癌患者呼吸道样本,分离、鉴定病原菌,并进行体外药物敏感性试验.结果 170例呼吸道样本中共检出202株非重复病原菌,其中革兰阴性菌127株(62.9％),居前3位的依次为铜绿假单胞菌(35株,17.3％)、鲍曼不动杆菌(28株,13.9％)和肺炎克雷伯菌(26株,12.9％);革兰阳性菌56株(27.7％),分离率最高的是金黄色葡萄球菌(35株,17.3％);真菌19株(9.4％).革兰阴性菌中,铜绿假单胞菌、鲍曼不动杆菌、肺炎克雷伯菌对碳青霉烯类抗菌药物的耐药率分别为22.8％、40.7％、3.8％.革兰阳性菌中,金黄色葡萄球菌对青霉素的耐药率为88.6％,未检出对万古霉素和利奈唑胺耐药的革兰阳性菌,耐甲氧西林金黄色葡萄球菌(MRSA)的检出率为28.6％.结论 肺癌患者化疗后肺部感染主要病原菌为革兰阴性菌,主要致病菌的耐药形势不容忽视,临床应合理使用抗菌药物.

目的 了解我院支气管肺泡灌洗液样本中的病原菌分布及其耐药性,为临床合理用药提供参考.方法 收集2016年1月至2019年12月我院送检的615例支气管肺泡灌洗液样本,分离、鉴定病原菌,并进行体外药敏试验.结果 共检出707株非重复病原菌,其中革兰阴性菌593株(83.9％),革兰阳性菌114株(16.1％);构成比占前3位的病原菌分别为铜绿假单胞菌(171株,24.2％)、肺炎克雷伯菌(147株,20.8％)和鲍曼不动杆菌(97株,13.7％).革兰阴性菌中,铜绿假单胞菌对碳青霉烯类抗菌药物的耐药率较高,对亚胺培南和美洛培南的耐药率分别为33.3％(57/171)和30.6％(52/170);肺炎克雷伯菌对碳青霉烯类抗菌药物的耐药率较低(<20％),产超广谱β-内酰胺酶菌株的检出率为16.3％(24/147);鲍曼不动杆菌的耐药率较高,对亚胺培南和美洛培南的耐药率均为85.6％(83/97).革兰阳性菌中,金黄色葡萄球菌对青霉素耐药率达89.4％(76/85),尚未发现对万古霉素和利奈唑胺耐药的革兰阳性菌,耐甲氧西林金黄色葡萄球菌的检出率为32.9％(28/85).结论 我院支气管肺泡灌洗液样本中的主要病原菌为革兰阴性菌,主要病原菌的耐药性不容忽视.支气管肺泡灌洗液病原菌检查对于疾病诊断和指导合理使用抗菌药物具有较高的临床价值.

目的 探讨白细胞(WBC)计数、中性粒细胞百分比(NEUT％)、红细胞分布宽度(RDW)、血清降钙素原(PCT)、中性粒细胞/淋巴细胞比值(NLR)单独和联合检测在血流感染(BSI)早期诊断中的应用价值.方法 回顾性分析海军军医大学附属长海医院2019年同时行血培养、PCT和血常规检测的住院患者的病历资料.根据血培养结果进行分组,以168例血培养阳性患者为感染组,以168例随机选取的血培养阴性患者为对照组,比较2组各项检测指标的差异.采用二元Logistic回归分析将WBC计数、NEUT％、RDW、PCT、NLR在早期诊断BSI中的作用进行方程拟合,采用受试者工作特征(ROC)曲线评价各项指标单独和联合检测早期诊断BSI的效能.结果 感染组WBC计数、NEUT％、RDW、PCT、NLR水平明显高于对照组(P<0.05).二元Logistic回归分析结果显示,PCT预测BSI的比值比(OR)最高(1.246);NEUT％诊断BSI的曲线下面积(AUC)最大(0.785),以86.35％为截断值,其早期诊断BSI的敏感性为68.45％、特异性为73.81％、准确性为71.13％;NEUT％与PCT联合检测,早期诊断BSI的AUC为0.819,以0.461为截断值,2项指标联合检测早期诊断BSI的敏感性为78.57％、特异性为69.64％、准确性为74.11％.结论 NEUT％、PCT、NLR可作为BSI早期诊断的指标,联合检测临床价值更大.

Objective:To investigate the distribution and drug resistance of pathogens causing blood stream infection in patients with pancreatic neoplasms.Methods:Clinical data of patients with pancreatic neoplasms complicated with bloodstream infection with confirmed pathological evidence admitted in the First Affiliated Hospital of Naval Medical University from January 2016 to June 2019 were collected. Bacteria were isolated from blood culture, and microbial sensitivity tests were analyzed by minimum inhibitory concentration and Kirby-Bauer methods. The distribution and drug resistance of pathogens causing blood stream infection in patients with pancreatic neoplasms were analyzed.Results:There were 116 cases (8.5%) with bloodstream infection in 1 372 patients with pancreatic neoplasms. A total of 156 bacterial strains were isolated from blood culture, of which 127 strains (81.4%) were gram negative aerobic bacteria, mainly including Escherichia coli (42 strains), Klebsiella pneumoniae (34 strains), Pseudomonas aeruginosa (12 strains), and 25 strains (16.0%) were gram positive aerobic bacteria, mainly including Enterococcus faecium (11 strains), Enterococcus faecalis (3 strains), Streptococcus angina (3 strains). 4 strains (2.6%) were anaerobic bacteria. The results of antibiotic susceptibility showed that the resistance rate of Escherichia coli to ampicillin was 90.5%, and to cefoperazone-sulbactam was 2.4%. The resistance rate of Klebsiella pneumoniae to piperacillin was 20.6%, and to cefoperazone-sulbactam was 5.9%. The resistance rate of Pseudomonas aeruginosa to imipenem was 41.7%, and no resistant strain was found to cefoperazone-sulbactam. The resistance rate of Enterococcus and Streptococcus pharyngitis to erythromycin were 85.7% and 33.3%, and no strains were resistant to vancomycin.Conclusions:The rate of blood stream infection in patients with pancreatic neoplasms was relatively high. In clinical practice, the distribution of pathogenic bacteria should be understood, the drug resistance should be monitored and antibiotics should be reasonably used, in order to maximally prevent and interfere with the occurrence of blood stream infection.

目的 了解医院耐碳青霉烯类肺炎克雷伯菌(CRKP)的分布特点、耐药性和分子生物学特征,为指导临床合理使用抗菌药物、防控CRKP院内传播提供依据.方法 收集我院2019年1月至12月临床分离的非重复CRKP菌株,采用VITEK 2 Compact全自动微生物分析仪和纸片扩散法(Kirby-Bauer法)进行细菌鉴定和药物敏感试验,采用WHONET 5.6软件对CRKP的检出率、标本来源、临床科室分布等进行统计分析.通过拉丝试验筛选高黏表型菌株,PCR检测碳青霉烯酶耐药基因、荚膜血清型和毒力基因.结果 共检出肺炎克雷伯菌532株,其中CRKP 140株(26.3％).CRKP菌株主要分离自痰/支气管肺泡灌洗液(66株,47.1％),其次为尿液(21株,15.0％).临床科室分布主要为心血管外科ICU(47株,33.6％)、烧伤科ICU(18株,12.9％)和急诊科(18株,12.9％).药物敏感试验结果显示CRKP除对替加环素敏感外,对其他抗菌药物的耐药率均在50％ 以上,其中对第1～4代头孢菌素类抗生素的耐药率均在85％ 以上,对碳青霉烯类药物的耐药率最高可达100.0％.耐药基因检测结果显示,121株CRKP中检出101株(83.5％)携带肺炎克雷伯菌碳青霉烯酶2(KPC-2)1种基因,7株(5.8％)携带苯唑西林酶48(OXA-48)1种基因,2株(1.7％)携带新德里金属 β-内酰胺酶1(NDM-1)1种基因,1株同时携带KPC-2和NDM-1基因,1株同时携带KPC-2和OXA-48基因,9株未检出目的耐药基因.15株(12.4％,15/121)CRKP拉丝试验阳性,其中13株为K64荚膜型,2株为K47荚膜型;14株检测到至少1种毒力基因.结论 我院CRKP临床分离率高,对多种抗菌药物耐药,以K64荚膜型高毒力CRKP为主,提示临床应进一步加强耐药监测,合理使用抗菌药物,以防止耐药菌株和高毒力菌株的传播和流行.

目的 了解耐碳青霉烯类肺炎克雷伯菌(CRKP)的分布特点及其耐药性,为指导临床合理使用抗菌药物提供依据.方法 收集2014年1月至2017年12月临床分离的CRKP菌株,采用自动化仪器法和纸片扩散法(K-B法)对上述菌株进行药物敏感性试验,药物敏感性结果严格按照美国临床和实验室标准化协会(CLSI)和美国食品药品管理局(FDA)标准判定.采用WHONET软件和SPSS 20.0软件对数据进行统计分析.结果 共收集临床分离CRKP菌株403株,主要标本来源为痰/支气管肺泡灌洗液(169株,占41.9％).CRKP首次分离标本来源不同,后续CRKP血流感染的发生率也不同,差异有统计学意义(P<0.05).CRKP来源科室位列前3位的分别为烧伤重症监护病房(30.0％,121/403)、消化科(8.4％,34/403)和急诊重症监护病房(7.2％,29/403).药物敏感性试验结果显示CRKP除对替加环素和磷霉素耐药率较低外,对其余抗生素的耐药率均>60.0％.结论 CRKP对多数常用抗生素呈现高度耐药.应加强对CRKP的耐药性监测,尤其是烧伤重症监护病房等重点科室,并采取有效措施预防和控制CRKP的传播.

目的 探讨血浆(1-3)-β-D葡聚糖检测(G试验)对真菌血流感染的诊断价值.方法 收集海军军医大学(第二军医大学)长海医院2015年1月至2017年12月临床各科室送检的进行真菌血培养和G试验的血液标本.分析264例真菌血培养阳性标本的来源科室分布和菌种分布情况.1678例同时进行真菌血培养和G试验,以真菌血培养阳性为标准,G试验结果>100.5 pg/mL为阳性,计算G试验诊断真菌血流感染的灵敏度、特异度、阳性预测值、阴性预测值;采用SPSS 19.0软件进行统计学分析,以受试者工作特征(ROC)曲线评估G试验对真菌血流感染的诊断价值.结果 2015—2017年共检出血培养阳性真菌264株,主要分布在肝胆外科(81株)、心血管外科(57株)、急救科(24株)、胸外科(22株)、血液科(16株)等科室;病原菌以假丝酵母菌属为主,其中近平滑假丝酵母菌最多(142株,占53.8％),其次为角膜假丝酵母菌(36株,13.6％)、白假丝酵母菌(20株,7.6％)和热带假丝酵母菌(18株,6.8％).1678例同时进行真菌血培养和G试验的患者中,137例真菌血培养结果为阳性.以真菌血培养阳性为标准,G试验诊断真菌血流感染的灵敏度、特异度、阳性预测值、阴性预测值分别为61.3％、87.9％、31.1％、96.2％;ROC曲线分析结果显示,G试验对真菌血流感染的诊断效能较好(曲线下面积为0.771,95％ 置信区间为0.723～0.819).137例真菌血流感染病例中,102例在血培养之前2～5 d进行了G试验,其中71例(69.6％)G试验结果为阳性.结论 血浆G试验诊断真菌血流感染的特异度较高,对真菌血流感染的早期诊断具有较好的阴性预测价值.

目的 分析烧伤患者院内感染病原菌的分布及耐药性,为烧伤患者院内病原菌感染的治疗提供依据.方法 收集2015年1月至2017年12月海军军医大学(第二军医大学)长海医院534例烧伤患者的各类临床标本,分离培养病原菌.使用VITEK 2 Compact全自动微生物分析仪或Microflex基质辅助激光解析飞行时间质谱仪进行细菌鉴定,使用VITEK 2 Compact全自动微生物分析仪进行细菌药物敏感性试验.结果 共分离出1219株病原菌.其中革兰阴性菌877株(71.9％),位列前4位的菌株分别为肺炎克雷伯菌(203株,16.7％)、铜绿假单胞菌(183株,15.0％)、鲍曼不动杆菌(176株,14.4％)和大肠埃希菌(101株,8.3％);革兰阳性菌342株(28.1％),位列前3位的菌株分别为金黄色葡萄球菌(136株,11.2％)、屎肠球菌(72株,5.9％)和粪肠球菌(60株,4.9％).病原菌主要来源于创面分泌物(577株,47.3％)、痰/支气管肺泡灌洗液(341株,28.0％)和尿液(147株,12.1％),93.5％(319/341)的痰/支气管肺泡灌洗液病原菌为革兰阴性菌.534例患者中有311例(58.2％)患者分离出2株及以上细菌.革兰阴性菌中肺炎克雷伯菌对常见抗菌药物的耐药率普遍偏高,呈现多重耐药趋势;铜绿假单胞菌耐药情况不容忽视,对碳青霉烯类抗菌药物的耐药率最高为35.5％;鲍曼不动杆菌对碳青霉烯类药物的耐药率最高达93.2％,对其他大部分抗菌药物耐药率>80.0％.革兰阳性菌中耐甲氧西林金黄色葡萄球菌检出率为69.1％(94/136),肠球菌属对常见抗菌药物的耐药率为38.9％～66.3％,但尚未发现对万古霉素、替加环素和利奈唑胺耐药的革兰阳性菌.结论 烧伤患者院内感染病原菌分布较为复杂,超过一半的患者呈多重细菌感染.最常见的致病菌为肺炎克雷伯菌,呈现多重耐药趋势.革兰阳性菌对万古霉素、替加环素和利奈唑胺敏感.

目的 分析临床真菌血流感染的病原菌分布及耐药特征,为真菌血流感染的诊治提供理论依据.方法 回顾性分析2015年1月～2017年12月临床真菌血流感染的菌株分布及药敏试验结果.结果 共分离264例真菌.近平滑念珠菌检出率最高(53.79％),其次是角膜假丝酵母(13.63％)和白念珠菌(7.58％).检出念珠菌数前三位科室依次为普外科(32.58％)、心血管外科(21.59％)和胸外科(8.33％).对氟康唑、伊曲康唑和伏立康唑的敏感率,白念珠菌均为100％;近平滑念珠菌分别为100％,99.3％和100％;角膜假丝酵母分别为94.4％,19.4％和97.2％.对于5-氟胞嘧啶,白念珠菌敏感率100％,近平滑念珠菌和角膜假丝酵母的敏感率仅为70.4％和11.1％.三者对两性霉素B的敏感率≥95％.结论近平滑念珠菌是该院临床血流感染最常见的真菌,绝大部分念珠菌对抗真菌药物的敏感率较高.要高度重视病原学监测,规范临床抗真菌药物的合理应用.

Objective To evaluate the accuracy of VITEK 2 Compact in the detection of the drug susceptibility of carbapenemresistant Klebsiella pneumoniae (CRKP) to Amikacin.Methods The susceptibility for 147 isolates of SRKP to Amikacin were detected by VITEK 2 Compact,disk diffusion method (K-B method) and E-test method,respectively.Results Among the 147 strains of Klebsiella pneumoniae,the drug susceptibility results were consistent between K B and E-test method.Among the 5 strains,the results were totally consistent by VITEK 2 Compact,K-B method and E test method,of which 4 strains were sensitive,1 strains were resistant.There were 142 strains being not consistent between VITEK 2 Compact and E-test method.The results of VITEK 2 Compact were sensitive or intermediate,while E test were drug resistance.Conclusion VITEK 2 Compact is not reliable for the detection of CRKP to Amikacin,which requires that K B method or other methods should be used for the susceptibility of CRKP to Amikacin.

食酸代尔夫特菌,属丛毛单胞菌科代尔夫特菌属.1999年Wen等学者[1]通过16S rRNA对丛毛单胞菌科的成员和一些未分类的菌株进行基因序列分析,将食酸从毛单胞菌从丛毛单胞菌属中移出,另立新属称为代尔夫特菌属.该菌广泛分布于自然环境中,如:水、土壤等,但在临床患者中较少分离得到,是人类少见的机会致病菌[2].由食酸代尔夫特菌感染引起的脑膜炎在临床上十分罕见,发病率低而不被临床医生熟悉,容易漏诊或误诊,严重影响患者的预后.

[收稿日期] 2018-04-24 [接受日期] 2018-07-11 [基金项目] 国家自然科学基金青年项目(31500721), 上海市科学技术委员会项目(17JC1400900), 上海青年临床医技人才(临床检验专业)培养资 助计划[沪医卫基 (2016)04 号]. Supported by National Natural Science Foundation of China for Young Scientists (31500721), Project of Science and Technology Commission of Shanghai Municipality (17JC1400900), and Training Program for Clinical Youth Medical Talents (Clinical Laboratory Specialty) in Shanghai (HYW201604). [作者简介] 刘 云,硕士,主管技师.E-mail: liuyun1258@163.com 通信作者(Corresponding authors). Tel: 021-31162069, E-mail: zhurrfight@foxmail.com; Tel: 021-31162075, E-mail: qinq78@163.com 器官移植患者院内感染病原体分布及其药敏分析 刘 云,钱 颖,黄晓春,万玉香,马 炜,李亚周,朱荣荣,秦 琴 海军军医大学(第二军医大学)长海医院实验诊断科,上海 200433

Objective To investigate the distribution and antimicrobial susceptibility of the bacteria isolated from bloodstream infections during 2013-2014 in Changhai Hospital for rational use of antibacterial agents.Methods The bacterial strains from blood samples were collected during the period from January 2013 through December 2014,and subjected to antimicrobial susceptibility testing by using automated system or Kirby-Bauer method.The results were interpreted according to CLSI M100-S24 breakpoints or FDA breakpoints.The data were analyzed by WHONET 5.6 software.Results A total of 1 048 nonduplicate isolates were collected,of which Escherichia coli,coagulase-negative Staphylococcus (CNS) and Klebsiella pneumoniae accounted for 29.5％,15.8％ and 13.8％,respectively.Gastroenterology,Hematology,General surgery,Urology and Department of Infectious Diseases are the top 5 departments according to their total number of bacterial isolates.The results of antimicrobial susceptibility testing showed that ESBLs-producing E.coli and K.pneumoniae accounted for 63.8％ and 38.6％,respectively.The prevalence of methicillinresistant CNS (MRCNS) was 77.6％.The E.coli strains isolated from Urology showed higher resistance rates to cephalosporins than the total E.coli strains,while the E.coli strains isolated from Gastroenterology showed higher resistance rates to betalactarn/beta-lactamase inhibitor combinations and carbapenems than the total E.coli strains.Higher prevalence of MRCNS was found in departments of Hematology,Urology and Neurosurgery.All the CNS strains isolated from Neurosurgery were resistant to methicillin.The K.pneumoniae strains isolated from Bum ICU had higher resistance rates to all the antibacterial agents tested than the total K.pneumoniae strains,while the K.pneumoniae strains isolated from Gastroenterology showed higher resistance rates to carbapenems and tigecycline than the total K.pneumoniae strains.Conclusions The pathogenic bacteria isolated from bloodstream infections vary with departments in terms of species distribution and antimicrobial susceptibility profile.It is necessary to strengthen the surveillance of antimicrobial resistance in hospital for rational use of antibiotics.