下呼吸道多重耐药性革兰氏阴性杆菌监测及临床意义

目的：监测多重耐药性革兰氏阴性杆菌（ＭＲＧＮＢ）,做到合理用药,提高感染治愈率。方法：１９９６年１月至１９９７年１２月至在上海第二医科大学新华医院,临床痰液标本中分离出８４１株革兰氏阴性杆菌（ＧＮＢ）。应用美国ＢＥＣＴＯＮ－ＤＩＣＫＩＮＯＮ公司的药敏检测板（ＭＩＣ法）,按ＮＣＣＬＳ标准判定敏感性。结果：８４１株ＧＮＢ同期细菌总数７１．５４％,ＮＢ中非发酵菌占６９．４６％,其中以铜绿假单胞菌最多见,     

Therapy of infections in neutropenic patients: Results with gentamicin in combination with cephalothin or chloramphenicol

Gentamicin in combination with cephalothin (Gent-Ceph) or with chloramphenicol (Gent-Chloro) was utilized in the treatment of 55 infections occurring in 49 cancer patients. Responses were obtained in 78% of the infections treated with Gent-Ceph and in 64% of those treated with Gent-Chloro. Pneumonia and septicemia were the most common infections in this study. Among the cases of pneumonia, 64% responded to Gent-Ceph and 67% to Gent-Chloro. Among the cases of septicemia, 88% responded to Gent-Ceph and 50% to Gent-Chloro. All of the identified organisms producing infection were gram-negative bacilli. Of these, E. coli was the most common. All organisms were resistant to cephalothin in vitro, and only 41% of them were resistant to chloramphenicol. However, resistant organisms responded significantly better to the Gent-Ceph combination (p < 0.025). Also, response to therapy among patients with severe neutropenia (< 100 neutrophils/mm³) was better for those patients treated with Gent-Ceph (p = 0.07). The combination of gentamicin with cephalothin or with chloramphenicol did not increase the frequency of side effects expected from gentamicin alone. No significant hematological toxicity was seen among those patients treated with chloramphenicol. Gentamicin in combination with cephalothin or chloramphenicol is an effective and safe antibiotic combination against gram-negative bacilli infections occurring in cancer patients. The efficacy of Gent-Ceph in patients with severe neutropenia is particularly advantageous.     

The impact of early adequate antimicrobial therapy on 14-day mortality in patients with monomicrobial Pseudomonas aeruginosa and Acinetobacter baumannii bacteremia

The impact of colistin therapy for early adequate antimicrobial therapy on clinical outcomes has rarely been evaluated in patients with Pseudomonas aeruginosa bacteremia (PAB) or Acinetobacter baumannii bacteremia (ABB). We investigated the impact of early adequate antimicrobial therapy on 14-day mortality in 149 patients with monomicrobial PAB and ABB at two medical centers where colistin treatment was frequently used. Patients who survived the first 14 days of PAB/ABB received adequate antimicrobial therapy within 3 days of bacteremia more frequently than those who died (53.3 vs. 38.6 %), although this finding is not statistically significant (p = 0.10). After excluding patients who received adequate colistin therapy, the difference was statistically significant (94.6 vs. 58.8 %, p = 0.001). In a multiple regression model excluding patients who received colistin therapy, adequate antimicrobial therapy within 3 days of bacteremia was a preventive factor for 14-day mortality (adjusted OR = 0.23, 95 % CI = 0.07–0.80, p = 0.02). In another multiple regression model including patients who received colistin, compared to inadequate antimicrobial therapy, adequate non-colistin therapy was a preventive factor for 14-day mortality (aOR = 0.22, 95 % CI = 0.07–0.78, p = 0.019), but adequate colistin therapy was not (aOR = 8.20, 95 % CI = 1.07–62.90, p = 0.043). The favorable impact of early adequate antimicrobial therapy on 14-day mortality in patients with monomicrobial PAB/ABB may be lessened in the clinical practice of using colistin frequently. Further studies may be needed to evaluate the clinical impact of colistin therapy in patients with PAB or ABB.     

Tn5090-like class 1 integron carrying blaVIM-2 in a Pseudomonas putida strain from Portugal

Three Pseudomonas putida strains containing bla_VIM-2 were isolated from an inanimate surface of a female ward sanitary facility in the Hospital Infante D. Pedro, Aveiro. A novel class 1 integron was found in strain Pp2 (aacA41bla_VIM-2/aac6'-IIc disrupted by an insertion sequence IS1382), and strain PpI was found to carry a class 1 integron (aacA7/bla_VIM-2/aacCl/aacA4), which is described for the first time in this species. Strain PFI carries a class 1 integron associated with a Tn5090-like transposon, constituting the first finding of this type of arrangement in a strain from Portugal. This association highlights further dissemination of bla_VIM-2 in environmental hospital isolates.     

5年感染病原菌分布与耐药性变化分析

目的探讨近5年医院急诊科感染病原菌的构成及耐药谱的动态变化,以指导临床医师合理应用抗菌药物。方法留取2004~2008年入住医院急诊ICU和急诊病房的感染患者可疑感染部位的痰液、血液、尿液、局部引流物和分泌物标本,应用法国生物梅里埃公司API系统鉴定菌种,采用K-B法测定20种抗菌药物敏感性。结果共收到标本2498份,检出阳性标本819份,总菌株培养检出阳性率为32.8%;分离出病原菌710株,其中革兰阴性杆菌487株,革兰阳性球菌223株,真菌109株,分别占59.5%、27.2%和13.3%;检出菌株前5位依次为大肠埃希菌、鲍氏不动杆菌、铜绿假单胞菌、金黄色葡萄球菌和白色假丝酵母菌;真菌感染有明显上升的趋势;药敏测定结果表明,革兰阴性杆菌和革兰阳性球菌的耐药率逐渐增加,亚胺培南和万古霉素对革兰阴性杆菌和革兰阳性球菌的耐药率较低。结论调查结果显示,医院科室感染患者中分离的病原菌耐药率较高且呈多药耐药,临床医师应参考药敏结果合理选用抗菌药物。     

老年病人产超广谱β-内酰胺酶革兰阴性杆菌感染的临床分析

目的　了解老年病人革兰阴性杆菌产超广谱 β 内酰胺酶菌的感染情况 ,指导临床合理使用抗生素。 方法　对本院1997年 1月— 2 0 0 0年 12月 5 4 1份老年患者的痰、尿、分泌物、血及各类导管标本中分离出的革兰阴性菌进行分析 ,采用双纸片协同试验检测产超广谱 β 内酰胺酶菌株 ,纸片扩散法测定产超广谱 β 内酰胺酶菌株对 17种抗生素的敏感性。 结果　老年病人革兰阴性杆菌产超广谱 β 内酰胺酶菌株的总检出率为 19 6 % ,分泌物和尿的检出率分别为 4 2 9%和30 8%。产超广谱 β 内酰胺酶菌株伊米配能和头孢哌酮 /舒巴坦的敏感性均达 10 0 %。 结论　对老年病人产超广谱 β 内酰胺酶菌株的感染临床宜选用伊米配能和头孢哌酮 /舒巴坦治疗     

Antimicrobial and antifungal activities of a novel cationic antimicrobial peptide, omiganan, in experimental skin colonisation models

Omiganan pentahydrochloride is a novel, synthetic, cationic, antimicrobial peptide that is being developed for the prevention of catheter-related infections and the treatment of acne and rosacea. In this study, the efficacy of topical omiganan gel was evaluated in two skin colonisation models (ex vivo pig skin and in vivo guinea pig skin). When tested in the ex vivo pig skin colonisation model, omiganan 0.1–2% gels exhibited potent dose-dependent activity against Gram-positive and Gram-negative bacteria and yeasts; the maximum effect was observed at 1–2%. No significant difference was noted in activity toward meticillin-resistant and meticillin-sensitive Staphylococcus aureus, and drug activity was not affected by the inoculum size. The antimicrobial activity of omiganan 1% gel was rapid, with a 2.7 log₁₀ colony-forming unit (CFU)/site reduction in Staphylococcus epidermidis counts at 1 h post application and a 5.2 log₁₀ CFU/site reduction at 24 h. Additional studies in the guinea pig skin colonisation model confirmed the potent antimicrobial and antifungal activities of omiganan 1% gel. In conclusion, omiganan gels have been demonstrated to be rapidly bactericidal and fungicidal, with significant dose-dependent activity against a broad spectrum of infectious organisms. These results further confirm that the drug has the potential as a topical antimicrobial agent.     

大鼠百日咳菌液脑水肿脑组织肿瘤坏死因子-α变化

目的　了解肿瘤坏死因子 α (TNF α)在百日咳菌液导致的感染性脑水肿 (感脑 )时的变化及与感脑脑损害的关系。方法　 99只大鼠随机分成空白对照组 (C组 ,n =11) ;生理盐水组 (NS组 ,n =44 ) ;百日咳菌液脑水肿组 (PB组 ,n =44 )。NS组和PB组又分为 30 ,6 0 ,12 0 ,2 40min 4个亚组。用RT PCR和ELISA方法检测不同时间大鼠感脑脑组织匀浆中的TNF αmRNA表达及蛋白质生成水平。结果　TNF α含量在PB 2 40min组 (76 8.4± 86 .3pg/ g)显著增加 ,分别与C组 (318.1± 31.1pg/ g) ,NS 30min(32 4.2± 6 5 .6 pg/ g) ,6 0min(32 2 .1± 73.4pg/g) ,12 0min(316 .8± 49.1pg/g) ,2 40min(32 9.9± 77.6 pg/g)及PB 30min(36 0 .3± 6 6 .6 pg/g) ,6 0min(35 8.5±49.1pg/ g) ,12 0min(35 6 .0± 5 2 .3pg/ g)组比较差异均有非常显著性 (P <0 .0 1)。TNF αmRNA表达信号在PB6 0min组开始增加 ,并随注菌后时间的增加 ,而逐渐增强 ,2 40min达高峰。结论　感脑时脑组织中的TNF α含量显著增加 ,提示TNF α与感脑脑损害密切相关。     

头孢吡肟等抗生素对革兰阴性杆菌体外敏感性连续四年耐药性监测分析

目的监测和了解头孢吡肟对临床常见革兰阴性菌体外抗菌活性。方法从1999～2002年收集的临床常见革兰阴性杆菌50528株(主要为尿液、痰、伤口及其分泌物标本)，连续监测4年。药物敏感性试验采用纸片扩散法，WHONET5软件进行结果分析。结果1999～2002年头孢吡肟对肠杆菌科细菌的敏感性为70．0％-95．2％；对铜绿假单胞菌敏感性为73．9％-77．5％。1999-2002年肠杆菌科细菌临床分离株对头孢噻肟、头孢他啶和头孢吡肟耐药性变迁的比较表明，头孢吡肟耐药率增加幅度低于头孢噻肟、头孢他啶；铜绿假单胞菌对头孢吡肟耐药率增加幅度明显低于哌拉西林、阿米卡星和头孢他啶。结论头孢吡肟对大肠埃希菌、肺炎克雷伯菌、弗劳地枸橼酸杆菌、产气肠杆菌、阴沟肠杆菌、奇异变形杆菌、铜绿假单胞菌和鲍曼不动杆菌有较好的体外抗菌活性。     

169例非发酵革兰阴性杆菌所致院内获得性肺炎的危险因素及耐药性分析

目的了解呼吸病房非发酵革兰阴性杆菌所致院内获得性肺炎的危险因素及耐药性,为临床医生治疗感染性疾病抗菌素的选择提供依据。方法细菌鉴定采用常规方法,API系统补充鉴定,药敏试验采用纸片扩散法,对169例非发酵革兰氏阴性杆菌引起的院内获得性肺炎患者的危险因素及耐药性的临床资料进行了回顾性分析。结果非发酵革兰阴性杆菌分离率62%,其中铜绿假单胞菌35.8%,不动杆菌12.8%,嗜麦芽窄食单胞菌6.9%,洋葱假单胞菌6.4%。临床资料显示,高龄、有严重的基础疾病、免疫功能受损、机械通气、以及高效、广谱抗菌素的应用,是非发酵革兰阴性杆菌定植的危险因素。而药敏试验显示,该组细菌对头孢菌素耐药率极高,对加酶抑制剂复方制剂、亚胺培南、丁胺卡那、头孢他啶、环丙沙星耐药率较低。结论非发酵革兰阴性杆菌是院内获得性肺炎的主要致病菌群,其耐药率高、难治性强,因此,建立系统防范措施,合理应用抗生素,控制高危因素是降低其感染发生的重要因素。