老年患者革兰阴性杆菌性肺炎的菌群分布及耐药性

目的 调查老年患者革兰阴性杆菌性肺炎的菌群分布及耐药性,为临床医师合理用药提供科学依据.方法 细菌培养和鉴定严格按照《全国临床检验操作规程》进行;药敏试验采用K-B法.结果 211株革兰阴性杆菌构成比依次为肺炎克雷伯菌占28.0％、铜绿假单胞菌占20.9％、大肠埃希菌占15.6％、鲍氏不动杆菌占10.0％等;主要革兰阴性杆菌对常用抗菌药物均产生了耐药性,肠杆菌科细菌对碳青霉烯类抗菌药物100.0％敏感,而铜绿假单胞菌及鲍氏不动杆菌对碳青霉烯类抗菌药物已产生了11.4％～14.3％的耐药率.结论 老年患者革兰阴性杆菌性肺炎的病原菌耐药性不断增强,应加大监测与控制力度.     

老年肺炎患者的病原菌分布及耐药性分析

目的 探讨老年患者革兰阴性杆菌肺炎的病原菌构成比及耐药性,为临床医师选择使用抗菌药物提供参考依据.方法 对277例老年革兰阴性杆菌肺炎患者的痰及下呼吸道分泌物进行常规细菌培养,用K-B法进行药物敏感试验并统计分析.结果 铜绿假单胞菌(PAE)分离率居首位,达26.7％;鲍氏不动杆菌(ABA)第2位,占23.5％;分离率居前5位的病原菌均显示了严重的耐药性,其中PAE、ABA泛耐药株检出率分别为18.9％、21.5％,嗜麦芽寡养单胞菌对亚胺培南100.0％耐药.结论 医院务必加强合理使用抗菌药物的管理工作,遏制细菌耐药性快速增长的不良趋势.     

基层医院多重耐药革兰阴性杆菌血行感染对患者住院结局的影响

目的 探讨多重耐药（MDR）革兰阴性杆菌血行感染与患者住院结局的相关性.方法 回顾分析2011-01-2012-12共254例革兰阴性杆菌血行感染的患者,其中89例为MDR革兰阴性杆菌感染.通过对比感染MDR革兰阴性杆菌和感染非MDR革兰阴性杆菌患者的住院时间、住院费用、ICU住院时间等住院结局相关事件,分析MDR革兰阴性杆菌血行感染与患者住院结局的相关性.结果 （1）感染MDR革兰阴性杆菌患者约占所有患者的35.0％;（2）在感染MDR革兰阴性杆菌的患者中,入院前使用抗生素治疗、合并腹部手术患者比例较高（均P＜0.01）,不恰当使用初始经验性抗生素比例较高（P＜0.01）,入住ICU的比例更高（P＜0.05）;（3）感染MDR革兰阴性杆菌的患者具有较高的30d病死率和较长的ICU住院时间,且抗生素治疗费用明显高于感染非MDR患者（均P＜0.05）;（4）多因素回归分析显示,感染MDR革兰阴性杆菌是患者院内死亡（OR=1.88,95％Cl=1.43～8.33,P=0.022）、较高抗生素治疗费用的独立因素（OR=1.54,95％ Cl=1.11～4.55,P=0.034）.结论 院内感染MDR革兰阴性杆菌使住院患者的病死率升高,增加了患者的住院费用,对患者的住院结局具有不良影响.     

Spontaneous bacterial peritonitis caused by Gram-negative bacteria: an update of epidemiology and antimicrobial treatments

ABSTRACT

Introduction: Spontaneous bacterial peritonitis (SBP) is a main infectious complication in end-stage liver disease (ESLD) patients. The increasing trend of bacterial resistance in ESLD patients with SBP has been associated with low treatment efficacy of traditional therapy. Cephalosporin use has been restricted to community-acquired infections and in areas/health care settings with low rates of multidrug-resistant (MDR) bacteria. To date, several changes are necessary with regard to empiric therapy recommendations in areas/health care settings with high rates of MDR bacteria.

Areas covered: An overview of the epidemiology and antimicrobial treatments of SBP caused by Gram-negative bacteria.

Expert opinion: Broad-spectrum antibiotics have been recommended as empiric therapy for suspected SBP in areas/health care settings with high rates of MDR bacteria and secondary treatment, with newer antibiotics, for SBP caused by MDR-Gram-negative bacteria (i.e. new beta-lactam/beta-lactamase inhibitor combinations, cefiderocol, plazomicin, and eravacycline) either alone or in combination.     

Combination therapy for Gram-negative bacteria: what is the evidence?

The treatment of infections caused by multidrug-resistant Gram-negative bacteria is challenging given the limited options for effective therapy. Combination therapy has garnered great interest recently, with the goals of ensuring appropriate therapy with at least one active agent, and achieving synergistic activity among the anti-microbials used. In this review, we evaluate the data supporting the use of combination therapy against Pseudomonas aeruginosa, carbapenem-resistant Enterobacteriaceae, Acinetobacter species and Stenotrophomonas maltophilia. Various regimens have been tried with promising results; however, the data are mostly derived from in vitro synergy studies. While these reports suggest an advantage of combination therapy over monotherapy, clinical data are scarce, and are comprised of retrospective and a few prospective observational studies. Well-designed randomized trials are needed to better elucidate the efficacy of the various combination regimens. Until then, this review offers a critical appraisal of the published literature and provides recommendations based on the available evidence.     

Mechanism of action and initial evaluation of a membrane active all-D-enantiomer antimicrobial peptidomimetic

Development of therapy against infections caused by antibiotic-resistant pathogens is a major unmet need in contemporary medicine. In previous work, our group chemically modified an antimicrobial peptidomimetic motif for targeted applications against cancer and obesity. Here, we show that the modified motif per se is resistant to proteolytic degradation and is a candidate antiinfective agent. We also show that the susceptibility of microorganisms to the drug is independent of bacterial growth phase. Moreover, this peptidomimetic selectively interferes with the integrity and function of the microbial surface lipid bilayer, data indicative that bacterial death results from membrane disruption followed by dissipation of membrane potential. Finally, we demonstrate two potential translational applications: use against biofilms and synergy with antibiotics in use. In summary, we introduce the mechanism of action and the initial evaluation of a prototype drug and a platform for the development of D-enantiomer antimicrobial peptidomimetics that target bacterial membranes of certain Gram-negative problem pathogens with promising translational applications.     

分泌带有PGL-I末端三糖内影像的单克隆抗独特型抗体杂交瘤的建立

用抗-PGL-Ⅰ末端三糖的单克隆抗体E_(10)F_1(MAb_1)免疫BALB/c鼠,取脾细胞与SP2/O骨髓瘤细胞融合,建立了两株分泌抗PGL-Ⅰ末端三糖的抗独特型抗体杂交瘤,命名为F_7B_7和F_7B_9。对F_7B_7做了鉴定,得以下结果:①F_7B_7能与E_(10)F_1发生特异反应;②交叉ELISA中和试验呈阳性反应:抗三糖阳性血清与含在半合成抗原NT-O-BSA中的三糖结合时受F_7B_7的抑制,其抑制程度呈剂量依赖关系;抗三糖阳性血清与F_7B_7的结合受NT-O-BSA的抑制,其抑制程度也呈剂量依赖关系。以上结果提示:杂交瘤F_7B_7是能分泌带有PGL-Ⅰ上三糖内影像的单克隆抗独特型抗体。对F_7B_7为替代抗原,作麻风病患者的血清学诊断的可能性和优越性进行了讨论。     

下呼吸道感染病原菌分离谱和细菌耐药性的变迁

目的:了解下呼吸道感染临床分离菌谱及其耐药性的变化趋势。方法:临床分离菌株经API系统鉴定分类,然后采用NCCLs琼脂二倍稀释法行药敏检测。采用WHONET5.3.SPSS12.0软件进行数据分析。结果:1995、1998年G-杆菌分别占当年总菌株数的73.9%和50.6%.2004年G+球菌占总菌株数的47%,经统计学比较发现G杆菌、G+球菌的构成比变化有显著差异(P<0.005),(G+球菌的感染率有升高。统计发现,G-杆菌以铜绿假单胞菌和肺炎克雷伯菌为主,两者对亚胺培南敏感率无变化(P<0.05);G+球菌以金黄色葡萄球菌、肠球菌属、凝固酶阴性葡萄球菌为主,3者对万古霉素、替考拉宁敏感率无变化,对苯唑西林耐药性增加(P<0.05)。2004年耐甲氧西林金葡菌的检出率为75%,凝固酶阴性葡萄球菌的分离率呈增高趋势。结论:本组资料对下呼吸道细菌性感染的治疗和抗菌药物的选择有参考价值。应重视下呼吸道感染病原菌的变化及耐药性监测,抗菌药物的选择应在体外细菌药敏试验指导下进行。     

Presental Cellulitis Caused by Mycobacterium intracellulare

A case of preseptal cellulitis caused by Mycobacterium intracellulare is presented. A 56-year-old white woman developed erythema, induration, and tenderness of the lids of her right eye after chalazion removal, which did not respond to three weeks of broad spectrum antibiotics. Incision and drainage with biopsy revealed granuloma, and acid-fast bacilli were seen. Mycobacterium intracellulare was isolated on culture, resistant to all the antimicrobials that the patient was given. Antimicrobial therapy was discontinued, and the infection resolved over 15 months.     

Septicemia in the newborn due to gram-negative bacilli

The case histories of 17 newborns developing septic shock due to gram-negative bacilli were studied for pre- and perinatal risk factors, clinical symptoms, and hematologic changes.Immaturity, resuscitation procedures, and hypothermia on admission were found to be the risk factors most frequently preceding septicemia. A skin color fading and changing from reddish-pink to yellow-green was the most early noticeable clinical symptom in all patients. The total leukocyte counts as well as the relative proportion of bands increased significantly at the onset of illness. When septicemia advanced, a marked drop of leukocytes was found, while the relative proportion of bands increased further. Only 1 in 12 cases showed a decrease in the platelet counts at the height of septicemia.A procedure for the early diagnosis of a neonatal septicemia is proposed: (1) Registration of perinatal risk factors. (2) With perinatal risk factors a skilled and attentive clinical observation is necessary. Particular attention should be paid to changes of skin color. (3) White blood cell picture: (a) every day in patients with perinatal risk factors and (b) every 6 h in patients showing suspicious symptoms.