应用随机扩增多态性DNA技术分型产气肠杆菌

目的：建立产气肠杆菌(EA)随机扩增多态性DNA(RAPD)技术基因分型谱。方法：以优化的反应体系和单一随机引物对临床分离的108株EA进行RAPD法基因分型并绘制基因分型图谱。结果：108株临床分离EA共得72种RAPD型。结论：RAPD技术可将临床分离的EA分为72型。     

产气肠杆菌临床分布及耐药性检测

目的了解医院感染产气肠杆菌临床分布及耐药情况,为临床用药提供参考。方法采用临床标本检验和药敏试验方法,对某医院2013年住院患者送检标本进行病原菌检测和药敏试验。结果从患者送检标本中分离到产气肠杆菌111例,主要分布于神经外科、肝胆外科和重症医学科的痰液和胆汁中。临床分离的产气肠杆菌对头孢西丁和头孢唑啉几乎100%耐药,对第四代头孢类比较敏感;对氨曲南产生耐药,但对亚胺培南和美罗培南等碳青霉烯类均比较敏感。结论该医院分离的产气肠杆菌耐药现象日益严重,对高危病区应完善和落实各项预防措施,严格无菌操作,加强对易感患者的监测。     

High-dose cefepime as an alternative treatment for infections caused by TEM-24 ESBL-producing Enterobacter aerogenes in severely-ill patients

This study evaluated retrospectively the efficacy of treatment with cefepime vs. a carbapenem, in combination with amikacin or ciprofloxacin, for seriously-ill patients infected with ESBL-producing Enterobacter aerogenes who were admitted to an intensive care unit. Forty-four episodes of infection were investigated in 43 patients: 21 treated with cefepime; 23 with a carbapenem. The two treatment groups did not differ statistically in terms of age, APACHE II scores, and infection sites, but the average duration of antibiotic exposure was significantly shorter in the cefepime group (8.5 days vs. 11.4 days; p 0.04). Clinical improvement was seen in 62% of patients receiving cefepime vs. 70% of patients receiving a carbapenem (p 0.59). Bacteriological eradication was achieved in 14% of patients receiving cefepime vs. 22% of patients receiving a carbapenem (p 0.76). The 30-day mortality rates related to infection were 33% in the cefepime group and 26% in the carbapenem group (p 0.44). Thus, outcome parameters did not differ significantly between the two groups. Nevertheless, a statistically significant increase in failure to eradicate ESBL-producing E. aerogenes was observed as the MICs of cefepime rose (p 0.017). Pulsed-field gel electrophoresis revealed three distinct clones, but one predominant clone harbouring the bla(TEM-24) gene was associated with most (42/44) of the episodes of infection. It was concluded that cefepime may be an alternative agent for therapy of severe infections caused by TEM-24 ESBL-producing E. aerogenes, although further studies are required to confirm these observations.     

42例产气肠杆菌肺炎临床分析

目的探讨产气肠杆菌肺炎的临床特点和抗生素敏感的分布;方法对42例产气肠杆菌肺炎的临床资料进行分析,同时以K-B法测定微生物的敏感性;结果≥70岁的患者32例(76.1%);有基础疾病的35例(83.3%),其中有肺基础疾病者18例(42.9%),院内感染22例(52.4%);临床主要表现为咳嗽、咳痰伴有发热18例(42.9%);胸片、CT以片状渗出为主要表现有40例(95.2%);药敏结果显示除对亚胺培南100%敏感,对头孢哌酮-舒巴坦95%敏感,头孢吡肟93%敏感,阿米卡星90%敏感外,对第三代头孢菌素的敏感性也在45%左右;结论产气肠杆菌肺炎好发于老年人,且大都伴有基础疾病,对抗生素敏感性差,应及早选择敏感抗生素以改善预后。     

随机扩增多态性DNA对新生儿病房产气肠杆菌基因分型

目的：建立产气肠杆菌随机扩增多态性DNA（RAPD）分析技术，用于新生儿病房产气肠杆菌流行病学调查。方法：对从新生儿病房两次集中分离出的产气肠杆菌进行抗生素最低抑菌浓度试验（MIC）和RAPD分析，结合患儿的临床及流行病学资料进行分析。结果：药敏谱分型与RAPD分型不完全一致。16株产气肠杆菌的RAPD分型分为9型。RAPD分型为Ⅰ、Ⅲ、Ⅷ型的10株产气肠杆菌是流行相关菌株，均为医院内获得，分别导致3次各不相关的水平传播。结论：药敏谱分型不能很好地区分菌株的株间差异。RAPD分型准确、操作简便，在48h内可确定流行株，是研究产气肠杆菌分子流行病学的有力工具。     

能量抑制剂CCCP对环丙沙星在阴沟肠杆菌内聚积的影响

目的：研究临床分离阴沟肠杆菌对环丙沙星的聚积以及能量抑制剂间苯腙氯羰氰（CCCP）对细菌摄取环丙沙星的影响,探讨主动泵出机制在细菌对喹诺酮耐药性产生中的作用.方法：应用荧光光度法测定阴沟肠杆菌细胞内环丙沙星的浓度,并对应用CCCP前后细菌细胞内环丙沙星聚积稳态浓度进行比较.结果：受试菌对环丙沙星的摄取均在5 min内达到稳态浓度,耐药菌株的稳态浓度低于敏感菌株,应用CCCP后耐药菌细胞内的环丙沙星聚积浓度明显增加.结论：细菌细胞内能量依赖的环丙沙星聚积浓度的减少,在阴沟肠杆菌对环丙沙星产生的耐药性中具有一定作用.     

阴沟肠杆菌耐药性观察

目的：监测阴沟肠杆菌的耐药性，探讨其变化规律，为有效控制感染和临床治疗提供依据。方法：对2001至2004年本院分离的革兰阴性杆菌使用VITEK2系统鉴定菌种，并用K-B纸片扩散法及微量肉汤稀释法（VITEK2系统测MIC）检测阴沟肠杆菌的体外耐药情况。结果：4年间阴沟肠杆菌的耐药率明显增高，头孢哌酮／舒巴坦、头孢他啶、头孢曲松、头孢吡肟等耐药率均有不同程度增高。到2004年底，亚胺培南仍保持着对阴沟肠杆菌的100％敏感率。结论：阴沟肠杆菌耐药现象日趋严重，须引起高度重视。     

Cleaning and disinfection of blenders used in hospital kitchens

The efficiency of a range of methods used to clean and disinfect blenders was compared. Blenders with metal, plastic and glass goblets were experimentally contaminated with Klebsiella aerogenes after which they were cleaned and disinfected by (a) cold water rinse, (b) detergent wash, (c) detergent wash and disinfectant soak, (d) detergent wash and boiling water rinse and (e) autoclaving. Autoclaving was the only procedure that sterilized the blenders but this could only be used for blenders with metal goblets. A detergent wash with or without chemical disinfection followed by a boiling water rinse was found to be the most effective method of cleaning and disinfecting all three types of blender.     

Cloning and sequencing of Enterobacter aerogenes OmpC-type osmoporin linked to carbapenem resistance

Using outbreak-related strains of Enterobacter aerogenes, we cloned and sequenced ompK39, the structural gene coding for outer membrane protein OmpK39. Its lack of expression was closely associated with a phenotype exhibiting low-level carbapenem resistance. Detailed alignment of the predicted amino acid sequence revealed that OmpK39 is a member of the OmpC subclass of enterobacterial porins, with the highest degree of homology to Klebsiella pneumoniae OmpK36. Based on a computerized alignment including Escherichia coli PhoE and OmpF, the 3D structures of which are known from X-ray studies, OmpK39 can be assumed to form the typical beta-barrel structure which is common to all enterobacterial porins. Since no inhibitory DNA sequences could be detected in ompk39 in the resistant strains, porin deficiency leading to carbapenem resistance seems to involve alterations in key regulatory genes and/or the promotor sequence rather than a direct mutation in the structural gene.     

综合ICU多重耐药产气肠杆菌流行特点分析

目的 了解笔者医院综合ICU病房多重耐药产气肠杆菌的流行特点.方法 收集笔者医院2014年5月1日~7月30日综合ICU病房内检出产气肠杆菌的患者,统计其相关临床资料,并对检出菌株进行药敏分析.结果 24例患者共检出33株产气肠杆菌,其主要来源为呼吸道标本,占72.7%(24/33).其中多重耐药菌株(multi-drug resistant,MDR)检出32株,占97.0%,广泛耐药(extensive-drug resistant, EDR)菌株检出7株,占21.2%.产气肠杆菌除对替加环素全部敏感外,对喹诺酮类、氨基糖苷类、β内酰胺复合制剂及β-内酰胺类抗生素的耐药率分别达到97.0%、78.8%、93.9%及90.9%.对碳青酶烯类抗生素亚胺培南、厄他培南及美罗培南的耐药率分别达到93.9%、90.9%和100%.结论 多重耐药产气肠杆菌对常用抗生素均具有很高的耐药率,临床工作者应予以重视并采取积极措施降低其耐药率.