新生儿耐甲氧西林凝固酶阴性葡萄球菌败血症40例分析

目的：探讨耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）在新生儿败血症中的分布,临床特征及耐药性特点。方法：应用全自动血培养系统（BACTE/9050）,ATB细菌鉴定仪,从80例新生儿血培养阳性瓶中分离出40株MRCNS。应用ATB药敏系统,测定了青霉素等17种抗生素的耐药性。结果：80株细菌中,分离出40株MRCNS（占50%）,其中溶血葡萄球菌17株（42.5%)居首位,表皮葡萄球菌15株（37.5%),其他葡萄球菌8株（20%）。药敏结果显示多重耐药。结论：凝固酶阴性葡萄球菌（CNS）已成为小儿血培养的第一位检出菌,主要为溶血葡萄球菌和表皮葡萄球菌,MRCNS占主导地位（达50%左右）,成为新生儿病房院内感染的主要致病菌。药敏结果显示MRCNS呈多重耐药,万古霉素及其他糖肽类抗生素是治疗MRCNS感染的首选药物,MRCNS在新生儿病房造成院内感染的危害性以及耐药性应引起广泛关注。     

凝固酶阴性葡萄球菌的鉴定

凝固酶阴性葡萄球菌的鉴定广东省雷州市人民医院检验科湛江５２４２００朱道朱海平随着近代医学的进展,在葡萄球菌感染疾病中,逐渐确认了凝固酶阴性葡萄球菌的多致病作用。近十年来,对凝固酶阴性葡萄球菌的鉴定和分类,已由原来的表皮和腐生葡萄球菌扩展到二十余种,其...     

凝固酶阴性葡萄球菌的临床意义

凝固酶阴性葡萄球菌（ＣＮＳ）是医院内感染的重要致病菌,本文介绍了临床标本中病原性ＣＮＳ的检出和鉴定以及测定其对抗生素的敏感性和致病性的最新方法。     

临床分离凝固酶阴性葡萄球菌细菌谱

目的了解玉溪市人民医院临床分离凝固酶阴性葡萄球菌（CNS）的菌种构成和耐药特征。方法对该院近6年来临床分离的808株CNS作回顾性分析。结果808株CNS共有16种;表皮葡萄球菌、腐生葡萄球菌和溶血葡萄球菌占CNS的77.2%;甲氧西林耐药（MRCNS）和甲氧西林敏感（MSCNS）各占63.3%和36.7%;β-内酰胺酶阳性检出率为84.5%,且MRCNS显著高于MSCNS（χ^2=50.88,P〈0.01）;药敏结果：MRCNS除万古霉素、呋喃妥因和利福平外,青霉素、氨苄西林等12种临床常用抗菌药物的耐药率在50.6%-100%,显示了高度的耐药性和多重耐药。结论CNS在临床标本中的检出范围广、种类多,以表皮葡萄球菌、腐生葡萄球菌和溶血葡萄球菌为主,MRCNS的高度耐药和多重耐药形势严重,加强CNS的细菌学监测非常必要。     

凝固酶阴性葡萄球菌感染的临床研究

对细菌学证实的７１例凝固酶阴性葡萄球菌感染病例进行了分析,结果为８个菌种葡萄球菌引起感染,９２％为院内感染,所致疾病以呼吸道感染,败血症,尿路感染及皮肤软组织感染为多见。细菌感染多发生在有基础疾病或免疫功能低下病人,混合菌感染多见,药敏示细菌对常用抗菌药物呈现高度耐药性,抗生素疗效欠佳。     

凝固酶阴性葡萄球菌临床耐药性的连续性研究

目的了解凝固酶阴性葡萄球菌的耐药性情况。方法分析2008年至2010年沈阳军区总医院临床分离的484株凝固酶阴性葡萄球菌的药敏结果。结果 2008年至2010年凝固酶阴性葡萄球菌的分离率分别为4.7%、3.6%和3.1%。耐甲氧西林凝固酶阴性葡萄球菌（MRSCN）分别为76.6%、78.5%和79.9%。青霉素G、红霉素和苯唑西林的耐药率较高,平均分别为91.2%、87.5%和82.6%。万古霉素、替考拉宁和利奈唑胺的耐药率均为0。结论 2008年至2010年凝固酶阴性葡萄球菌检出率相对稳定,对常用抗菌药物的耐药率相对稳定,这为临床用药选择及加强感染控制提供了有力指导。     

凝固酶阴性葡萄球菌分布及耐药性研究

本文对１３６株ＣＮＳ进行ＡＰＩ分类,ＰＣＲ检测ＭＲＣＮＳ及纸片法药敏测定,结果表明ＣＮＳ感染以表皮葡萄球菌（占６１７６％）、溶血葡萄球菌（占２５０％）为主。ＭＲＣＮＳ已成为院内感染重要病原菌,占ＣＮＳ的７８７％。纸片法药敏结果显示ＣＮＳ对青霉素类、喹诺酮类、大环内酯类、磷霉素、氯霉素耐药较高,约为４０～７０％,有些高达８０～９０％,而对利福平、米诺环素、阿米卡星、奈替米星及某些头孢菌素类耐药率较低,对万古霉素、去甲万古霉素全部敏感,且ＭＲＣＮＳ的耐药率显著高于ＭＳＣＮＳ（ｐ＜０００１）。     

426株凝固酶阴性葡萄球菌临床分布及耐药性分析

目的:分析凝固酶阴性葡萄球菌(CNS)的分布及耐药性,为临床合理应用抗菌药物提供理论依据.方法:对我院2005年1月-2007年12月临床分离的CNS采用琼脂纸片扩散法(K-B法)检测药敏.结果:在426株CNS中共分离13种菌,其中表皮葡萄球菌、溶血葡萄球菌、人葡萄球菌分别为218株、103株、46株,各占51.17%、24.18%和10.80%;CNS对氟霉素、阿米卡星的耐药率小于25%,对万古霉素和替考拉宁的耐药率为0%;对青霉素、笨唑西林、红霉素、头孢西丁、哌拉西林、庆大霉素和环丙沙星的耐药率大于50%.从CNS中检出的耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)和甲氧西林敏感的凝固酶阴性葡萄球菌(MSCNS)分别为350株和76株,分别占82.16%和17.84%;MRCNS对多种抗菌药物耐药,与MSCNS相比差异有显著性统计学意义(p＜0.01).结论:需要加强量CNS病原学耐药性监测,了解其分布特点,及时向临床反馈公布,为临床医师合理应用抗菌药物提供依据.     

新生儿凝固酶阴性葡萄球菌败血症血降钙素原、C反应蛋白、白细胞及血小板计数变化及其意义

目的观察新生儿凝固酶阴性葡萄球菌(CNS)败血症患儿血降钙素原(PCT)、C反应蛋白(CRP)、白细胞(WBC)及血小板(PLT)水平的变化,探讨其与新生儿CNS败血症的关系。方法选择2013年至2014年住院的新生儿CNS败血症患儿38例作为观察组,另选同时期收住无感染症状的32例新生儿为对照组,比较两组患儿入院后血PCT、CRP、WBC及PLT水平和阳性率的差异,并观察这些指标诊断新生儿CNS败血症灵敏度和特异度。结果观察组PCT水平、阳性率显著高于对照组(P0.05),两组患儿CRP、WBC、PLT水平及阳性率比较差异无统计学意义(P0.05),PCT诊断新生儿CNS败血症灵敏度高于CRP、WBC及PLT,但特异度低于后三者。结论新生儿CNS败血症无特异性实验室检查方法,PCT对新生儿CNS败血症早期诊断有一定的价值,联合检测PCT、CRP、WBC及PLT能提高诊断的准确率,血培养阳性仍是诊断新生儿CNS败血症的金标准。     

重症监护病房凝固酶阴性葡萄球菌分布及耐药性分析

目的了解重症监护病房(ICU)凝固酶阴性葡萄球菌(CNS)临床分布及耐药情况,以期指导临床合理使用抗菌药物。方法采用VITEK-2细菌鉴定及药敏分析系统,对2009年10月至2010年9月重症监护病房的患者各类标本分离的凝固酶阴性葡萄球菌进行鉴定和药敏试验。结果共检出CNS 189株,以表皮葡萄球菌和溶血葡萄球菌为主,占71.42%。耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)122株,分离率为61.5%,β-内酰胺酶检出率达100%,MRCNS对青霉素、红霉素、苯唑西林耐药率最高,分别达100%、93.44%、91.80%,对复方新诺明、喹诺酮类药的耐药率次之,对利福平、呋西地酸、替考拉宁、喹奴普汀/达福普汀等耐药率均较低;甲氧西林敏感凝固酶阴性葡萄球菌(MSCNS)67株,分离率为38.5%,β-内酰胺酶检出率为61.1%,MSCNS对大多数抗生素敏感;189株CNS中未检测到万古霉素耐药株。结论 ICU分离的CNS以表皮葡萄球菌和溶血葡萄球菌为主,MRCNS检出率高且呈多重耐药,万古霉素、呋西地酸、替考拉宁、喹奴普汀/达福普汀是治疗MRCNS感染的首选药物。     

6类抗生素耐药基因在耐甲氧西林凝固酶阴性葡萄球菌中的分布及分析

目的了解6类抗生素耐药基因在耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）中的分布情况,为抗生素的合理使用及感染控制提供依据。方法应用K-B纸片扩散法对6种抗生素进行药敏试验,聚合酶链反应（PCR）对6类耐药基因进行检测。结果 MRCNS对氨苄西林、红霉素、四环素、庆大霉素和莫匹罗星的耐药率分别为100%、87.50%、30.21%、61.46%和27.08%,未检测出对万古霉素的耐药菌株;mecA、ermB、ermC、msrA、tetM、tetK、aac（6’）/aph（2＂）、aph（3’）-III和mupA耐药基因的阳性检出率分别为100.0%、10.42%、77.08%、46.86%、5.21%、2.08%、75.00%、39.58%和25.00%,未检测出ermA、ant（6’）-I、vanA和vanB耐药基因。结论 MRCNS能同时携带多种抗生素耐药基因,为多重耐药菌。     

Methicillin resistance in Staphylococcus aureus and coagulase-negative staphylococci: epidemiological and molecular aspects

Infections caused by the genus Staphylococcus are of great importance for human health. Staphylococcus species are divided into coagulase-positive staphylococci, represented by S. aureus, a pathogen that can cause infections of the skin and other organs in immunocompetent patients, and coagulase-negative staphylococci (CNS) which comprise different species normally involved in infectious processes in immunocompromised patients or patients using catheters. Oxacillin has been one of the main drugs used for the treatment of staphylococcal infections; however, a large number of S. aureus and CNS isolates of nosocomial origin are resistant to this drug. Methicillin resistance is encoded by the mecA gene which is inserted in the SCC mec cassette. This cassette is a mobile genetic element consisting of five different types and several subtypes. Oxacillin-resistant strains are detected by phenotypic and genotypic methods. Epidemiologically, methicillin-resistant S. aureus strains can be divided into five large pandemic clones, called Brazilian, Hungarian, Iberian, New York/Japan and Pediatric. The objective of the present review was to discuss aspects of resistance, epidemiology, genetics and detection of oxacillin resistance in Staphylococcus spp., since these microorganisms are increasingly more frequent in Brazil.     

老年患者血培养病原菌分布及耐药性调查

目的了解老年患者血液感染的病原菌种类以及对抗菌药物的耐药状况。方法对2290份老年住院患者血培养标本中186例培养阳性检出菌及药敏结果进行统计学分析。结果在分离的172株细菌中,革兰阴性菌、革兰阳性菌及真菌分别占54.7%、34.9%和10.5%;革兰阴性菌中以大肠埃希菌占绝对优势(20.9%),假单胞菌其次(10.5%),革兰阳性菌中以凝固酶阴性葡萄球菌(CNS)占绝对优势(20.9%),金黄色葡萄球菌仅为2.9%。药敏试验表明老年菌血症的病原菌对常用抗菌药物的耐药严重,尤其是CNS及假单胞菌属细菌表现为较高的耐药率及多重耐药性。结论老年菌血症病原菌以机会致病菌感染比例较高,致病菌耐药问题严重,及时监测老年致病菌的变迁和耐药发展趋势以指导临床用药至关重要。     

凝固酶阴性葡萄球菌菌谱与药敏谱调查

目的了解中山大学附属第三医院临床分离凝固酶阴性葡萄球菌（CNS）的菌种构成与耐药性。方法采用MicroScan WalkAway-40全自动微生物鉴定仪及配套阳性菌药敏复合板进行菌种鉴定与药敏试验,nitrocefin法测定β-内酰胺酶。结果表皮葡萄球菌与溶血葡萄球菌共占CNS的70．4％;甲氧西林耐药株（MRCNS）与甲氧西林敏感株（MSCNS）各占77．8％、22．2％;药敏试验结果提示MRCNS仅对万古霉素、呋喃妥因敏感,MSCNS对大多数抗生素敏感,未检出万古霉素耐药与中介株;β-内酰胺酶在MRCNS、MSCNS中的检出率分别为91．7％、78．1％。结论临床分离的CNS以表皮葡萄球菌和溶血葡萄球菌为主,MRCNS多重耐药现象严重,宜密切监测CNS的分离状况与耐药性,并严格限制万古霉素在临床上的应用,以避免耐万古霉素CNS的出现与流行。     

Strict infection control measures do not prevent clonal spread of coagulase negative staphylococci colonizing central venous catheters in neutropenic hemato-oncologic patients

Coagulase negative staphylococci (CoNS) are a main cause of catheter related infections (CRI). Earlier studies (1994-1996) revealed a high incidence of CRI (6 per 1000 catheter days) among neutropenic hemato-oncologic patients in the Erasmus MC Hematology Department (Rotterdam, The Netherlands). This was mainly explained by expansion of two methicillin resistant Staphylococcus epidermidis (MRSE) clones (Nouwen et al., J. Clin. Microbiol. 36 (1998) 2696-2702). In a new, 16-bed unit in the same institution, we investigated the effect of strict clinical isolation measures on the incidence of CRI. During two 6-month screening periods (period I: April 1998-December 1998 and period II: April 1999-October 1999) all patients receiving a central venous catheter were prospectively monitored for the development of CRI. During period I every visitor of the cubicles had to wear hair caps, masks, gowns and gloves. During period II these procedures were abolished, but hands were cleansed using alcohol and masks were worn during both periods in case of coughing and sneezing. All CoNS strains isolated from blood cultures were genetically classifies by pulsed field gel electrophoresis (PFGE). The incidence of CRI during period I was 13.0 per 1000 catheter days, in comparison to 9.6 in period II (P=0.84). During this latter period, 19 CRI were diagnosed, 14 catheter related bacteremia episodes (CRB) and five local infections. Seventy-two percent (n=9) of CRB were due to a CoNS. The mean catheter survival until appearance of a CRI increased from 43 days during period I to 78 days in period II (P=0.39). The mean catheter survival until infection related removal was increased from 43 days to 133 days (P=0.12). During period I less experienced intervention radiologists introduced the catheters, which may have limited the efficacy of the strict hygiene measures. Thus, abolishing strict isolation precautions had no negative effect on the incidence of CRI. After genotyping of 38 MRSE strains isolated from blood and central venous catheter cultures of 12 patients in period II, eight PFGE types were found. Three types were found in more than one patient, but based on epidemiological data patient-to-patient spread could not be proven. No genotypic identity between patient and personnel CoNS isolates was shown and the two major clonal types that were present between 1994 and 1996 were not encountered. However, from December 1998 onwards new MRSE clones could be identified (types E and J). In conclusion, despite a constant rate of CRI and implementation of optimal patient care, clonal spread of MRSE strains was not prevented by strict hygiene measures.     

Ecology and dynamics of coagulase-negative cocci isolated from naturally fermented Italian sausages

Coagulase-negative cocci (CNC) ecology in naturally fermented sausages from Friuli Venezia Giulia region, in the North East of Italy, was investigated. A total of 617 CNC strains, isolated from three different plants during the fermentation process, were identified by traditional methods (biochemical tests) and molecular methods based on species specific PCR, PCR-Denaturing Gradient Gel Electrophoresis (DGGE) and sequencing of the V3 region of the 16S rRNA gene. The identification, by using biochemical tests, was not successful for 130 strains. Moreover, incongruent results were observed comparing the traditional with the molecular identifications. The same species of CNC were found in all three processing plants, but their contribution to the fermentations was different. In two plants Staphylococcus xylosus was the main species involved in fermentation process, while in the third the maturation was carried out equally by three species: S. xylosus, Staphylococcus warneri and Staphylococcus pasteuri.     

206株凝固酶阴性葡萄球菌的临床分布及耐药性分析

目的分析凝固酶阴性葡萄球菌（CNS）的临床分布及耐药情况,指导临床合理用药。方法采用ATB-Expression细菌鉴定系统对厦门市妇幼保健院2009年1月至2009年12月分离的206株CNS进行鉴定,用K-B纸片法检测其对苯唑西林等10种抗菌药物的敏感度。结果206株CNS菌分布于8类临床标本,血液、生殖道标本分离率较高,分别为52．91％、25．24％。耐甲氧西林（MRS）的发生率分别为：模仿葡萄球菌59．09％,溶血葡萄球菌95．83％,表皮葡萄球菌80．00％,人型葡萄球菌85．71％。对青霉素、红霉素耐药率较高,分别为85％和82％以上;对左氧氟沙星、克林霉素耐药性次之;未检出对万古霉素、替考拉宁耐药菌株。结论该院分离的CNS耐药性严重,MRS发生率高达59％以上,对红霉素、克林霉素高度耐药,临床应尽量减少青霉素、红霉素等药物的经验性用药,依据药敏结果选择抗菌药物进行治疗,防止耐药菌株爆发院感流行。