Antimicrobial resistance among clinical isolates of Pseudomonas aeruginosa from patients in a teaching hospital, Riyadh, Saudi Arabia, 2001-2005

Antimicrobial resistance to nine anti-pseudomonal agents (azteronam, ceftazidime, cefepime, piperacillin/tazobactam, imipenem, meropenem, ciprofloxacin, amikacin and gentamicin), the magnitude of multidrug resistance, associated underlying conditions, and mortality among patients with Pseudomonas aeruginosa isolates from King Khalid University Hospital, Riyadh, Saudi Arabia from 2001 to 2005 were determined. The results showed that antimicrobial resistance among P. aeruginosa is gradually increasing for most anti-pseudomonal agents, particularly aztreonam, ceftazidime, piperacillin/tazobactam and imipenem. There were 19 (3%) and 12 (2%) multidrug-resistant (MDR) P. aeruginosa patients in 2004 and 2005, respectively, and MDR P. aeruginosa was more commonly found in non-intensive care unit (ICU) patients. Most MDR isolates were from surgical and diabetic patients. The mortality rate was higher among ICU patients.     

呼吸机相关性肺炎病原学与细菌耐药性变迁的临床研究

目的调查安徽省铜陵市人民医院近10年来呼吸机相关性肺炎（VAP）病原学构成与细菌耐药性的变迁。方法比较两个不同时间段（1996年6月～2001年6月和2001年7月～2006年6月）病原学分布特点及细菌耐药性的变迁。结果10年间，有完整病历资料、接受有创机械通气的患者共1236例，VAP发生率为44．34％（538／1236）；在538例VAP中，2种及2种以上致病菌感染占56．51％；革兰阴性细菌中，铜绿假单胞菌和不动杆菌属为VAP的主要致病菌（68．63％）（385／561）；表皮葡萄球菌感染为VAP的主要革兰阳性致病菌（75．40％）（95／126）；真菌占20．98％（183／872）；铜绿假单胞菌在两个时间段所占比例无明显变化，不动杆菌属的检出率呈上升趋势（8．23％～15．23％）；铜绿假单胞菌和不动杆菌属对亚胺培南、头孢他啶的敏感性明显下降，耐苯唑西林表皮葡萄球菌的检出率显著升高（18．75％～71．43％）。结论铜绿假单胞菌和不动杆菌属是我院VAP的主要革兰阴性致病菌，10年间，致病菌的分布及细菌耐药菌性已经发生了明显的变化，临床初始经验性治疗面临更大的难度。     

1998年上海地区细菌耐药性监测

目的 对上海医院中临床分离菌进行耐药性监测,指导临床合理用药。方法 用Ｋｉｒｂｙ－Ｂａｕｅｒ法进行药敏试验,根据１９９７年ＮＣＣＬＳ判断结果。结果 临床分离菌中革兰阳性球菌有增多趋势。金黄色葡萄球菌（ＳＡ）和凝固酶阴性葡萄球菌（ＣＮＳ）中耐甲氧西林ＳＥＡ（ＭＲＳＡ）和耐甲氧西林ＣＮＳ（ＭＲＣＮＳ）分别约占７０．７％和５４．９％但对万古霉素均敏感,肠球菌属中万古霉素耐药株约５％,克雷白菌属,沙雷菌属     

PCR identification and automated ribotyping of Pseudomonas aeruginosa clinical isolates from intensive care patients

Nosocomial isolates of Pseudomonas aeruginosa exhibit high rates of resistance to antibiotics, and are often multidrug resistant. P. aeruginosa clinical isolates (n = 56) were obtained from ICU patients in a hospital in Pakistan over a 3-y period. Antimicrobial susceptibility of the 56 P. aeruginosa clinical isolates was investigated using 7 antibiotics and the resistance rates were as follows: aztreonam (68% resistant), ceftazidime (67%), imipenem (66%), ofloxacin (59%), amikacin (56%), gentamicin (44%), and piperacillin-tazobactam (27%) (p < 0.01). In addition, 55% of the P. aeruginosa clinical isolates were resistant to 4 or more antibiotics. Imipenem-resistant strains were frequently associated with ceftazidime, ofloxacin, aztreonam, and more strikingly, amikacin resistance (p < 0.05). PCR (using P. aeruginosa-specific primers VIC1 + VIC2 and P1 + P2, respectively) was highly specific and sensitive, and was positive for all 56 P. aeruginosa isolates tested. Automated ribotyping was used to investigate the clonal diversity of the 56 P. aeruginosa isolates. Automated ribotyping indicated that the clinical isolates were clonally related and could be clustered into 4 major ribogroups based on their similarity index, with ribogroup II being the dominant one. The P. aeruginosa isolates in ribogroup II were correlated with their antibiotic resistance pattern and, interestingly, there seemed to be a gradual acquisition of multiple antibiotic resistance associated with the isolates within this group over time. The ribotyping data, together with the antibiotic resistance profile, provide valuable molecular epidemiology information for the control of hospital-acquired P. aeruginosa infections.     

Ventilator-associated pneumonia due to colistin susceptible-only microorganisms.

Acinetobacter spp. and Pseudomonas aeruginosa are common pathogens of ventilator-associated pneumonia (VAP). The presentation and outcome of VAP due to Acinetobacter spp. and P. aeruginosa susceptible to carbapenems (Carb-S; imipenem and/or meropenem) and to colistin only (Col-S) were compared in the present retrospective study in three intensive care units. A total of 61 episodes of VAP caused by Acinetobacter spp. or P. aeruginosa were studied, of which 30 isolates were Carb-S and 31 were Col-S. Demographics, worsening of renal function and mortality were not different. The univariate analysis showed that a later onset and a previous episode of VAP, prior antimicrobial therapy for >10 days and previous therapy with carbapenems during the present admission were more frequent in patients with Col-S strains. On multivariate analysis, prior antimicrobial therapy for >10 days and a previous episode of VAP remained significantly associated with Col-S VAP. Approximately 41% of the infections caused by Col-S isolates, but none of those due to Carb-S isolates, had received prior carbapenem therapy. Colistin-susceptible ventilator-associated pneumonia episodes can be effectively treated using colistin without significant renal dysfunction. This susceptibility pattern could be suspected in patients with a previous ventilator-associated pneumonia episode or prior antibiotic therapy for >10 days preceding the present ventilator-associated pneumonia episode.     

Occurrence and antimicrobial resistance pattern of inpatient and outpatient isolates of Pseudomonas aeruginosa in a Saudi Arabian hospital: 1998-2003.

OBJECTIVES: The objective of this study was to describe the pattern and trends of antibiotic resistance of Pseudomonas aeruginosa over a six-year period in a Saudi Arabian hospital. METHODS: This was a retrospective study of the antibiotic resistance of outpatient and inpatient isolates of P. aeruginosa. Only one isolate per patient per year was included in the study. RESULTS: During the study period a total of 2679 isolates of P. aeruginosa were available for analysis. Outpatient isolates constituted 48% of the total number, and of these 23.4% were obtained from wound cultures. For the inpatient isolates, 33.6% and 30% were obtained from the respiratory tract and wounds, respectively. There was no significant increase in the resistance rates of outpatient isolates to the tested antibiotics over time. On the other hand, inpatient isolates showed a statistically significant increase in resistance rates to piperacillin, ceftazidime, imipenem, and ciprofloxacin (p<0.001). Over the study period, the resistance rates of outpatient and inpatient isolates to piperacillin, ceftazidime, imipenem, and ciprofloxacin were 4.6% and 11.5%, 2.4% and 10%, 2.6% and 5.8%, and 3% and 6%, respectively. Gentamicin demonstrated the highest resistance among all tested aminoglycosides for outpatient isolates (6%) and inpatient isolates (6.7%). Resistance to more than two classes of antibiotics was present in 1-2% of inpatient isolates and in 0% of outpatient isolates. CONCLUSION: Antibiotic resistance continues to be a problem especially in inpatient isolates and is likely to be related to increased antibiotic use. Thus, continued monitoring of antibiotic resistance is of great importance to ensure the proper use of antibiotics and to detect any increasing trends in resistance.     

急诊监护病房呼吸机相关性肺炎影响因素及其病原菌特点分析

目的 分析急诊监护病房中呼吸机相关性肺炎(ventilator-associated pneumonia,VAP)的影响凶素和致病菌耐药状况.方法 收集2005年5月至2008年5月VAP患者的病原学资料,并与同期未出现VAP患者进行比较.结果 ①机械通气(mechanical ventilation,MV)≥48 h患者178例,65例患者出现VAP(36.5%),18例死亡(病死率27.7%),VAP组病死率明显高于非VAP组(P=0.001);②VAP主要的致病菌以革兰阴性杆菌为主(占77.1%),尤其是绿脓杆菌和鲍曼不动杆菌分离率居多并显示多重耐药:77.3%绿脓杆菌显示出对头孢他啶耐药,72.7%对左氧氟沙星耐药,18.2%对亚胺培南耐药;75.0%的鲍曼不动杆菌对头孢他啶耐药,80.0%对左氧氟沙星耐药,25.0%对亚胺培南耐药;③logistic分析结果显示MV≥7d、应用激素与VAP存在相关性(P<0.05).而广谱抗生素或接触抗生素在3种以上者与VAP致病菌的多重耐药存在显著的相关性(P<0.001).结论 VAP患者具有MV时间长、住院时间长、病死率高等特点;MV≥7 d、应用激素容易导致VAP的发生;VAP的致病菌以多重耐药的革兰阴性细菌为主,广谱抗生素或3种以上抗生素的应用是VAP耐药菌产生的独立危险因素.     

ICU呼吸机相关性肺炎病原菌分布和耐药性分析

目的了解我院ICU呼吸机相关性肺炎(ventilator-associated pneumonia,VAP)的病原菌分布和耐药性状况,为临床合理应用抗菌药物提供病原学依据。方法回顾性分析2014年1月—2016年12月我院ICU诊断为VAP的118例患者的基本资料,并分析气管深部分泌物的病原菌的构成比和药敏试验结果。结果从118例VAP确诊患者气管深部分泌物中共检出130株病原菌。其中革兰阴性菌103株(79.23%),革兰阳性菌20株(15.38%),真菌7株(5.38%)。革兰阴性菌主要包括:鲍曼溶血不动杆菌33株(32.04%),粘质沙雷菌20株(19.42%)、肺炎克雷伯杆菌18株(17.47%),铜绿假单胞菌11株(10.68%),大肠埃希菌10株(9.71%);革兰阳性菌主要为金黄色葡萄球菌10株(50.00%)。其中粘质沙雷菌、肺炎克雷伯菌、铜绿假单胞菌和大肠埃希菌对亚胺培南和阿米卡星的耐药率均低于10.00%,而鲍曼溶血不动杆菌对多种常见抗生素的耐药率均超过80.00%(美罗培南81.97%、阿米卡星83.61%、头孢曲松88.33%、左氧氟沙星80.33%)。金黄色葡萄球菌对万古霉素、利奈唑胺和替考拉宁均敏感。结论我院ICU中VAP患者感染主要以革兰阴性菌为主,且存在多重耐药现象。了解VAP的病原菌分布和耐药性,对于合理应用抗生素、提高治愈率等方面有极大帮助。     

重症监护病房鲍曼不动杆菌的耐药性分析

目的对近年重症监护病房（ICU）中的鲍曼不动杆菌的耐药性进行分析,指导经验应用抗生素。方法回顾2000年1月至2004年12月自ICU患者分离的鲍曼不动杆菌,分析其药敏结果。结果5年共分离的鲍曼不动杆菌156株,以痰标本为主,占91％。常用抗生素中亚胺培南对鲍曼不动杆菌保持较高的抗菌活性（87％～90％）,对阿米卡星、氨苄西林／舒巴坦、头孢他啶、哌拉西林、环丙沙星等多种抗生素的耐药性较高,且有逐年增高的趋势。结论ICU中鲍曼不动杆菌表现为多重耐药。应重视医院致病菌的耐药性监测,根据其结果应用抗生素。     

Antibiotic sensitivity pattern of the bacteria isolated from nosocomial infections in ICU

The incidence of nosocomial infections in ICU is 4-5 times greater than in general ward. Critically ill patients are always at higher risk of developing nosocomial infections with resistant strains. This study is an attempt to know the antibiotic sensitivity pattern of the common isolates in ICU. Samples comprising urine, blood, endotracheal secretions and throat swabs were collected from 102 ICU patients of them, 56 patients showed evidence of nosocomial infection (54.9%), from whom 120 different organisms were isolated. Antibiotic sensitivity test was done according to Kirby Bauer method. Klebsiella pneumoniae were the most prevalent isolates from respiratory tract infections followed by Proteus spp, Escherichia coli, Staphylococci spp. and Acinetobacter spp. The gram negative enteric bacilli were uniformly resistant to betalactam antibiotics as well as betalactam-betalactamase inhibitors. Resistance to Ciprofloxacin and Ceftriaxone ranged from 50-100% and 25-83.3% respectively. Staphylococci were 100% resistant to penicillin and tetracycline, 80% to cotrimoxazole, 60% to erythromycin and gentamicin and 40% to amikacin. Acinetobacter spp. were highly resistant to most of the antibacterial agents except gentamicin while Pseudomonas spp. showed 75% resistance to it. The increased prevalence of resistant organisms in ICU probably reflects lack of proper antibiotic policy resulting in prolonged and indiscriminate use of antimicrobial agent.     

High antibiotic susceptibility among bacterial pathogens in Swedish ICUs. Report from a nation-wide surveillance program using TA90 as a novel index of susceptibility

Local infection control measures, antibiotic consumption and patient demographics from 1999-2000 together with bacteriological analyses were investigated in 29 ICUs participating in the ICU-STRAMA programme. The median antibiotic consumption per ICU was 1147 (range 605-2143) daily doses per 1000 occupied bed d (DDD1000). Antibiotics to which > 90% of isolates of an organism were susceptible were defined as treatment alternatives (TA90). The mean number of TA90 was low (1-2 per organism) for Enterococcus faecium (vancomycin:VAN), coagulase negative staphylococci (VAN), Pseudomonas aeruginosa (ceftazidime:CTZ, netilmicin: NET) and Stenotrophomonas maltophilia (CTZ, trimethoprim-sulfamethoxazole: TSU), but higher (3-7) for Acinetobacter spp. (imipenem:IMI, NET, TSU), Enterococcus faecalis (ampicillin:AMP, IMI, VAN), Serratia spp. (ciprofloxacin:CIP, IMI, NET), Enterobacter spp. (CIP, IMI, NET, TSU), E. coli (cefuroxime:CXM, cefotaxime/eftazidime:CTX/CTZ, CIP, IMI, NET, piperacillin-tazobactam:PTZ, TSU), Klebsiella spp. (CTX/CTZ CIP, IMI, NET, PTZ, TSU) and Staphylococcus aureus (clindamycin, fusidic acid, NET, oxacillin, rifampicin, VAN). Of S. aureus isolates 2% were MRSA. Facilities for alcohol hand disinfection at each bed were available in 96% of the ICUs. The numbers of TA90 available were apparently higher than in ICUs in southern Europe and the US, despite a relatively high antibiotic consumption. This may be due to a moderate ecological impact of the used agents and the infection control routines in Swedish ICUs.     

常见非发酵菌的耐药性分析

目的 了解常见非发酵菌的临床分布及耐药情况，指导临床合理使用抗菌药物。方法 2003年1月～2004年12月临床分离的铜绿假单胞菌281株、不动杆菌属190株及嗜麦芽窄食单胞菌63株，用Kirby—Bauer法进行药敏试验。结果 591株非发酵菌中以铜绿假单胞菌（47．5％）、不动杆菌属（32．1％）及嗜麦芽窄食单胞菌（10．7％）为主；主要分布于痰液（62．4％）、皮肤软组织创面分泌物（22．7％）中；耐药性分析显示铜绿假单胞菌对亚胺培南的敏感性最高（92．9％），其它依次为头孢他啶（78．3％）、环丙沙星（78．1％）、头孢吡肟（74．4％）、阿米卡星（70．5％）、哌拉西林-他唑巴坦（70．1％）、头孢哌酮-巴坦（67．9％）、哌拉西林（60．3％）、氨曲南（57．5％）、头孢哌酮（57．1％）、替卡西林-克拉维酸（55．7％）；不动杆菌属对亚胺培南的敏感性也最高（95．7％），其它依次为头孢哌酮-舒巴坦（66．7％）、头孢吡肟（59．3％）、替卡西林-克拉维酸（57．4％）、阿米卡星（55．0％）、哌拉西林-他唑巴坦（51．6％）；嗜麦芽窄食单胞菌对头孢哌酮-舒巴坦的敏感性最高（75．6％），其它依次为头孢他啶（75．5％）、复方磺胺甲嗯唑（74．5％）、替卡西林-克拉维酸（73．7％）、环丙沙星（69．8％）、头孢吡肟（63．4％）、哌拉西林-他唑巴坦（56．8％），对包括亚胺培南在内的其它常用抗菌药物均高度耐药。结论 细菌耐药有一定的地区性，定期对本地区细菌耐药性进行监测，对合理使用抗菌药物、减少耐药菌株的产生和流行有重要的临床指导价值。     

Need for improved antimicrobial and infection control stewardship in Vietnamese intensive care units

Objective Survey of antibiotic consumption, microbial resistance and hygiene precautions in the intensive care units of three hospitals in northern Vietnam. Methods Observational study. Data were collected from the microbiological laboratories. Antibiotic consumption was determined based on quantities of drugs delivered from the pharmacy. A protocol to observe the application of hygiene precautions was developed and used. Bacteria were typed and tested for drug susceptibility using the disc‐diffusion method. Results The mean antibiotic consumption was 811 defined daily doses per 1000 occupied bed days. The most commonly used antibiotics were third‐generation cephalosporins, followed by carbapenems, amoxicillin and ampicillin. Eighty per cent of bacterial isolates were Gram‐negative. The most common pathogens found in blood cultures were Escherichia coli and Klebsiella spp., Pseudomonas spp., Acinetobacter spp., Staphylococcus aureus and Enterococcus faecalis. Acinetobacter and Pseudomonas spp. were the two most frequently isolated bacteria from the respiratory tract and all other sources together. Seventy per cent of Acinetobacter species showed reduced susceptibility to imipenem, 80% to ciprofloxacin and 89% to ceftazidime. Forty‐four per cent of Pseudomonas spp. showed reduced susceptibility to imipenem, 49% to ciprofloxacin and 49% to ceftazidime. Escherichia coli was fully susceptible to imipenem, but 57% of samples were resistant to both ciprofloxacin and cefotaxime. Hygiene precautions were poor, and fewer than 50% of patient contacts incorporated appropriate hand hygiene. Conclusion Low antibiotic consumption, poor hygiene precautions and the high level of antibiotic resistance indicate that there is room for improvement regarding antibiotic use and infection control.     

头孢哌酮－舒巴坦体外抗菌作用研究

为评价头孢哌酮（ｃｅｆｏｐｅｒａｚｏｎｅ，ＣＰＺ）－舒巴坦（ｓｕｌｂａｃｔａｍ，ＳＢＴ）合剂的体外抗菌作用，观察了ＣＰＺ－ＳＢＴ对１１４６株临床分离菌的抗菌活性，并与ＣＰＺ及其他抗菌药物进行比较。ＣＰＺ－ＳＢＴ对产β－内酰胺酶菌株的抗菌活性高于ＣＰＺ，在需氧革兰阴性杆菌８３４株中，对ＣＰＺ耐药者１６５株，其中９４株（５７．０％）对ＣＰＺ－ＳＢＴ呈现敏感。ＣＰＺ－ＳＢＴ扩大了抗菌谱，其对不动杆菌属、脆弱类杆菌等具有良好抗菌作用。与受试的其他抗菌药物相比，该合剂对肠杆菌科、绿脓杆菌和不动杆菌属等的抗菌活性与头孢他啶、阿米卡星、环丙沙星相仿，较亚胺培南略差；对脆弱类杆菌等厌氧菌的作用则与亚胺培南、替门汀和甲硝唑相仿。上述结果提示ＣＰＺ－ＳＢＴ为一新的广谱抗菌药，具有良好的临床应用前景，可用于耐头孢哌酮革兰阴性杆菌（包括绿脓杆菌）而对本合剂呈现敏感菌所致的严重感染的治疗。     

Epidemiology and clinical outcomes of patients with multiresistant Pseudomonas aeruginosa.

We conducted a case-series study of multiresistant Pseudomonas aeruginosa in patients who did not have cystic fibrosis. Patient characteristics, antibiotic exposures, time course of emergence of resistance, and clinical outcomes were examined. Twenty-two patients were identified from whom P. aeruginosa resistant to ciprofloxacin, imipenem, ceftazidime, and piperacillin was isolated. Nineteen (86%) had clinical infection. Patients received prolonged courses of antipseudomonal antibiotics before isolation of multiresistant P. aeruginosa. Nine of 11 patients with soft-tissue infection exhibited resolution of clinical infection but usually required surgical removal of infected tissue with or without revascularization. Overall, three patients died. In two instances in which multiple isolates with different susceptibility profiles from the same patient were available, pulsed-field gel electrophoresis profiles of serial isolates were indistinguishable or closely related. This study illustrates that multiresistant P. aeruginosa emerges in a stepwise manner after exposure to antipseudomonal antibiotics and results in adverse outcomes.     

沧州地区重症监护病房呼吸机相关性肺炎病原学分析及防治

目的 对沧州地区呼吸机相关性肺炎(ventilator-associated pneumonia,VAP)的病原菌分布、耐药情况及预后进行临床研究,以期指导临床治疗.方法 对2008年1～12月在沧州市3家三级甲等医院261例行机械通气治疗患者中发生VAP的106例患者进行临床病例的统计,对致病菌进行细菌鉴定,采用纸片扩散法检测其耐药性,采用单因素分析方法 进行预后分析.结果 VAP平均发病时间为机械通气后7 d,VAP发生率41.0%,病死率35.0%.106例VAP患者呼吸道分泌物中分离出病原菌共126株.其中革兰阴性细菌103株(81.7%),革兰阳性细菌18株(14.3%),真菌5株(4.0%).铜绿假单胞菌37株(29.3%),鲍曼不动杆菌26株(20.6%),肺炎克雷伯菌18株(14.3%),洋葱假单胞菌9株(7.2%),大肠埃希菌9株(7.2%).嗜麦芽窄食单胞菌6株(4.8%),阴沟肠杆菌2株(1.6%),脑膜脓毒性黄杆菌2株(1.6%),金黄色葡萄球菌9株(7.1%),凝固酶阴性葡萄球菌5株(3.9%),肠球菌3株(2.4%),依次为沧州地区VAP患者最常见的病原菌.致病菌仍以细菌尤其是革兰阴性杆菌为主,铜绿假单胞菌居首位.革兰阴性细菌对头孢菌素等各种常见抗菌药物耐药情况均十分严重.本研究中VAP大多数病例为迟发性VAP.机械通气时间>7 d的VAP发生率显著高于<7 d组.>60岁患者发生VAP明显高于≤60岁患者.应用H2受体阻滞剂组的VAP发生率较未用组高.气管插管VAP发生率显著低于气管切开.VAP总病死率为35%,其中严重低白蛋白血症,肾功能衰竭合并葡萄球菌感染和抗生素治疗不当为预后不良的危险因素.结论 沧州地区VAP病原菌耐药严重,病死率高,须加强预防及合理进行经验性抗生素治疗.     

Prevalence and antibiotic susceptibility of Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae in Estonian intensive care units in comparison with European data

This prospective cohort study was performed from April to December 2003 for the purpose of collecting a maximum of 50 non-duplicate isolates of Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae from each of 4 ICUs to determine minimum inhibitory concentrations. The most prevalent species were Enterobacteriaceae (13%), K. pneumoniae and A. baumannii (both 12%). 60% of A. baumannii strains were susceptible to ampicillin/sulbactam and cefepime, 95% to meropenem and imipenem, and 75% to amikacin. 79% of P. aeruginosa strains were piperacillin/tazobactam, 58% ceftazidime, 81% meropenem, 72% imipenem, 69% ciprofloxacin and 97% amikacin susceptible. The susceptibility of K. pneumoniae to meropenem and imipenem was 99%, to ciprofloxacin was 91% and to amikacin was 98%. Gram-negative bacteria (especially K. pneumoniae and A. baumannii) were prevalent in our ICUs compared to other European studies. Carbapenem susceptibility of Estonian strains was higher, but P. aeruginosa sensitivity to ceftazidime was lower, compared to other EU countries.     

Antimicrobial resistance among Gram-negative bacteria isolated from intensive care units in a Cardiology Institute in Istanbul, Turkey

Antibiotic resistance among Gram-negative rods (GNRs) causing hospital-acquired infections poses a threat, particularly to intensive care unit (ICU) patients. This study was undertaken in order to achieve the following: to detect the frequency of GNRs isolated from coronary and surgical ICUs at the Institute of Cardiology, Istanbul University, between January 2000-December 2002; to compare the resistance of these GNRs to selected antibiotics; and to determine the prevalence of extended-spectrum beta-lactamases (ESBLs). A total of 367 isolates were obtained from 171 patients. Susceptibility testing and detection of ESBLs were performed using the E-test method. Ceftazidime-clavulanate was used for the detection of ESBLs. The majority of microorganisms were isolated from the respiratory tract (45.5%) and blood (36.7%). Acinetobacter baumannii was the most frequently isolated GNR (24.5%), followed by Pseudomonas aeruginosa (22%). ESBL positivity was found to be 21.1%. High rates of the ESBLs of Escherichia coli and Klebsiella pneumoniae were observed, i.e., 27.7 and 57.5%, respectively. High rates of resistance to all antibiotics studied were observed. The most active agent against the majority of the isolates was imipenem (79.2%), followed by levofloxacin (77%) and ciprofloxacin (71%).     

Evolution, incidence, and susceptibility of bacterial bloodstream isolates from 519 bone marrow transplant patients.

Bacteria remain an important cause of infection in bone marrow transplants. To examine shifts in the etiology and susceptibility of bacterial isolates from transplants, we reviewed the incidence and susceptibility of blood isolates during a 7-year period. The infection rate fell dramatically during this time. Gram-positive organisms were isolated more often than gram-negative organisms, but the trend is reversing. Streptococci surpassed staphylococci for 5 years as the leading pathogen. Increasing resistance to penicillin, ciprofloxacin, and imipenem was noted in Streptococcus species. With the exception of type 1 beta-lactamase-producing bacteria and Pseudomonas aeruginosa, gram-negative isolates remained overall susceptible to ceftazidime. Increased antibiotic prophylaxis coincided with the reduction in percentage of infected patients and increase in resistance to beta-lactam antibiotics. Mortality attributed to bacteremia was low except for infections caused by P. aeruginosa and the Enterobacter, Serratia, Citrobacter group. There was no mortality attributable to gram-positive organisms such as Staphylococcus aureus and viridans streptococci.     

老年VAP嗜麦芽寡养单胞菌感染及耐药性分析

目的研究老年VAP嗜麦芽寡养单胞菌(SMA)感染及耐药特征。方法从161例老年患者分离的30株嗜麦芽寡养单胞菌采用纸片扩散法进行药敏试验,并对抗生素耐药结果进行回顾性分析。结果30株嗜麦芽寡养单胞菌对氨苄西林、亚胺培南、美罗培南、头孢唑啉、氨曲南、庆大霉素、阿米卡星高度耐药(100%,96.67%,96.67%,93.33%,80.00%,73.33%);对头胞吡肟,头胞他啶,头胞噻肟耐药率较高(50.00%,50.00%and60.00%),对左氧氟沙星,环丙沙星耐药率接近50%(40.00%,46.67%);但对复方新诺明、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦耐药率较低(3.33%, 10.00 %,16.67%)。结论嗜麦芽寡养单胞菌对常用抗菌药物呈多重耐药,在老年VAP感染已十分严重,它的首选药物为复方新诺明、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦。