临床标本革兰阴性杆菌的分布及药物敏感性研究

目的 分析医院临床分离革兰阴性(G-)杆菌的分布及药物敏感性, 指导临床使用抗生素.方法 回顾性分析医院2005年7月至2006年11月临床分离G-杆菌资料.结果 在分离出848株细菌中,检出G-杆菌共566株,阳性率为66.7%,G-杆菌前4种细菌依次是铜绿假单胞菌、大肠埃希菌、肺炎克雷伯菌和醋酸钙-鲍曼复合不动杆菌.15种抗生素的敏感率显示:亚胺培南的敏感率最高(大于87.7%),头孢曲松与头孢他啶分别为53.0%和78.8%以下.氨苄西林、氨苄西林/舒巴坦、头孢唑啉和复方新诺明对G-杆菌前4种细菌敏感率为43.2%以下,头孢曲松、呋喃妥因对铜绿假单胞菌敏感率小于4.0%,亚胺培南是治疗铜绿假单胞菌的特效抗生素,敏感率为87.7%,其耐药性有升高趋势.结论 铜绿假单胞菌是G-杆菌引起医院感染的首位病原菌,醋酸钙-鲍曼复合不动杆菌引起的感染稳步上升.近年来,细菌多重耐药性且耐药率有上升趋势,对第3代头孢菌素和亚胺培南的耐药性明显增强.临床应选用细菌培养敏感的抗生素,以减少细菌耐药性的产生,提高治疗效果.     

下呼吸道感染分离革兰阴性杆菌的耐药性分析

目的分析我院下呼吸道感染患者临床分离常见革兰阴性细菌对常用抗菌药物的耐药性,指导临床合理使用抗菌药物。方法收集下呼吸道感染患者痰或支气管肺泡灌洗液,常规细菌培养、分离后,经VITEK-AMS 60自动分析仪鉴定,应用K-B法测定对抗菌药物的敏感性。结果临床分离常见革兰阴性杆菌前3位依次为不动杆菌属（25.4%）、铜绿假单胞菌（16.2%）、肺炎克雷伯杆菌（15.4%）。不动杆菌属细菌对第3代头孢菌素中的头孢哌酮/舒巴坦（4.0%）和头孢他啶（4.0%）、第4代头孢菌素（4.0%）、氟喹诺酮类（10.8%）、氨基糖甙（10.8%）及亚胺培南（9.5%）耐药率较低。铜绿假单胞菌对头孢吡肟耐药率最低（4.3%）,其次分别是左氧氟沙星（19.1%）、阿米卡星（25.2%）、环丙沙星（25.5%）,对亚胺培南的耐药率高达55.3%。肺炎克雷伯杆菌除哌拉西林耐药率19.1%外,对常用抗生素的耐药性相对较低。结论我院下呼吸道感染分离革兰阴性杆菌以不动杆菌位居首位,常见革兰阴性杆菌对抗生素呈不同程度耐药性。铜绿假单胞菌对亚胺培南耐药现象十分严重,应根据药敏结果用药。加强对院内感染和本地区、本院及本病区临床分离菌的耐药监测,对合理经验选择抗生素非常重要。     

医院内感染非发酵革兰阴性杆菌的病原学与耐药性监测研究

目的了解医院内感染病例中非发酵革兰阴性杆菌(NFGNB)的分离分布情况及耐药性。方法分析和总结3年来全国医院感染监控网医院报告的NFGNB资料。结果NFGNB占同期报告医院感染病原体的19．68％，占G-杆菌的42．41％。铜绿假单胞菌、不动杆菌属、嗜麦芽窄食单胞菌分别占NFGNB的46．53％、19．88％、7．35％；3年间，鲍曼不动杆菌由13．27％上升至23．50％、嗜麦芽窄食单胞菌由5．93％上升至8．44％；不同NFGNB耐药性存在明显差异，铜绿假单胞菌对亚胺培南、头孢他啶、头孢哌酮，不动杆菌对亚胺培南、环丙沙星及嗜麦芽窄食单胞菌对SMZ、环丙沙星、头孢哌酮耐药性均较低。结论NFGNB是医院感染主要病原菌之一，特别是铜绿假单胞菌、不动杆菌、嗜麦芽窄食单胞菌。     

引起医院内感染的革兰阴性杆菌96株统计分析

目的 了解引起本院医院内感染的革兰阴性杆菌的菌群分布和耐药率变化情况,指导临床合理使用抗生素,有效地控制医院内感染.方法 统计分析本院连续两年分离的引起医院内感染的96株革兰阴性杆菌的菌群分布和它们对11种抗生素的耐药率.结果 各病区分离率最高的医院内感染革兰阴性杆菌为大肠埃希菌(33.3%),其他依次为铜绿假单胞菌(18.7%),克雷伯菌属细菌(17.7%),不动杆菌属细菌(16.6%),肠杆菌属细菌(11.5%),嗜麦芽寡养假单胞菌(2.1%).呼吸道标本分离率最高(60.4%),其他标本依次为尿液(14.6%)、分泌物(11.5%)、胆汁(7.3%)、引流液(5.2%)、血液(1.0%).两年中,总耐药率最低的抗生素是亚胺培南(13.4%),其他耐药率较低的抗生素为头孢哌酮/舒巴坦(13.6%),阿米卡星(20.5%),头孢吡肟(25.3%).大肠埃希菌和肺炎克雷伯菌中的超广谱β-内酰胺酶的发生率从2009年的49.0%和38.2%升高到2010年的53.2%和55.1%.结论 经呼吸道、尿路、手术产生的医院内感染占有较大比重,应加强对环境卫生、介入治疗、手术治疗的监控力度.大肠埃希菌、不动杆菌属细菌和肠杆菌属细菌均对亚胺培南保持很高的敏感性,铜绿假单胞菌对头孢他啶和阿米卡星的敏感性也较高,在临床工作中应加强对抗生素使用的监督.     

In vitro activity of doripenem (S-4661) against multidrug-resistant gram-negative bacilli isolated from patients with cystic fibrosis

Doripenem 50% inhibitory concentrations (MIC50) and 90% inhibitory concentrations (MIC90) for multidrug-resistant strains of mucoid Pseudomonas aeruginosa (n=200 strains), nonmucoid P. aeruginosa (n=200), and Burkholderia cepacia complex (n=200) isolated from patients with cystic fibrosis were 8 and 32, 8 and 64, and 8 and 32 microg/ml, respectively. Doripenem had somewhat better activity than established antimicrobial agents.     

下呼吸道感染中非发酵菌耐药性分析

目的：探讨非发酵菌所致下呼吸道感染的临床特点及细菌耐药性。方法：分析天津市区10所医院呼吸科收治的494例非发酵菌致下呼吸道感染资料。结果：所收治的494例中．社区获得性肺炎占多数。高龄、重症基础疾病、长期应用抗生素或激素、气管插管及导管留置时间过长是非发酵菌导致下呼吸道感染的危险因素。其临床表现缺乏特异性。检出非发酵菌各属细菌的比例依次为不动杆菌属(57．3％)、铜绿假单胞菌(33．5％)、嗜麦芽窄食单胞菌(4．6％)、其他假单胞菌(2．4％)和其他(2．2％)。药敏结果显示非发酵菌严重耐药，亚胺培南耐药性最低。非发酵菌对第三代头孢菌素及氨曲南、氨苄西林高度耐药。加用β内酰胺酶抑制剂的第三代头孢菌素的耐药率大大低于未加用者。结论：非发酵菌致下呼吸道感染临床表现无特异性．治疗时应根据药敏结果选择应用抗生素。     

In vitro activity of cefpiramide (SM-1652) against gram-negative bacilli

The susceptibilities of 317 gram-negative bacilli to cefpiramide, cefotaxime, and piperacillin were determined by standardized microdilution and disk diffusion tests. Cefpiramide and piperacillin were more consistently active against nonfermenters than against Enterobacteriaceae, whereas cefotaxime was more active against Enterobacteriaceae. Inhibitory zone diameters of approximately 75-micrograms cefpiramide disks correlated well with minimal inhibitory concentrations (r = 0.85); breakpoints for defining susceptibility and resistance were recommended.     

Fourth-generation cephalosporins: in vitro activity against nosocomial gram-negative bacilli compared with beta-lactam antibiotics and ciprofloxacin

The in vitro activity of two new expanded spectrum fourth-generation cephalosporins, cefepime and cefpirome, was compared with that of five antibacterial agents, ceftazidime, cefoperazone, cefotaxime, imipenem, and ciprofloxacin, that are commonly used in the treatment of serious infections caused by aerobic gram-negative bacteria. The agar dilution method described by the US National Committee for Clinical Laboratory Standards was used to determine the minimum inhibitory concentrations of antibiotics tested. Three hundred and two clinical isolates, representing a cross-section of Klebsiella and Enterobacter species and Pseudomonas aeruginosa were tested. The most potent beta-lactams were imipenem, cefepime, and cefpirome, which demonstrated significant activity against the majority of strains in all three genera of bacteria, as did ciprofloxacin. Ceftazidime was active against P. aeruginosa, but was less potent against Klebsiella and Enterobacter species. Cefoperazone and cefotaxime were less active than ceftazidime against P. aeruginosa. Cefepime had slightly greater activity than cefpirome against the gram-negative bacteria tested. These data indicate that cefepime and cefpirome are highly active against many frequently resistant nosocomial bacterial strains that are traditionally responsible for difficult-to-treat infections.     

常见革兰阴性杆菌临床分离株对碳青霉烯类等抗菌药物的耐药性分析

目的 调查常见革兰阴性杆菌临床分离株对碳青霉烯类等抗菌药物的耐药性,为临床治疗提供依据。 方法 采用回顾性分析方法,调查2009年1月至2011年12月从温州医学院附属第一医院住院患者分离的2361株革兰阴性杆菌对碳青霉烯类等抗菌药物的耐药性,其中肠杆菌科细菌1832株,非发酵菌529株。 结果 肠杆菌科细菌对碳青霉烯类抗菌药物的耐药较低。大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌、产气肠杆菌、粘质沙雷菌、摩根摩根菌和产酸克雷伯菌对亚胺培南的耐药率分别为0.2%(2/1053)、3.0%(15/504)、2.9%(3/102)、9.5%(7/74)、21.7%(10/46) 、10.7%(3/28)和16.0%(4/25);对美罗培南的耐药率分别为0.4%(4/1053)、3.4%(17/504)、3.9%(4/102)、8.1%(6/74)、19.6%(9/46)、14.3%(4/28)和16.0%(4/25)。非发酵菌对碳青霉烯类抗生素的耐药率高,鲍曼不动杆菌、铜绿假单胞菌、洋葱伯克霍尔德菌对亚胺培南的耐药率分别为76.8%(209/272)、37.2%(55/148)和73.4%(80/109);对美罗培南的耐药率分别为73.9%(201/272)、33.8%(50/148)和69.7%(76/109)。肠杆菌科细菌和非发酵菌对其他10种抗生素均呈较高的耐药率。 结论 碳青霉烯类抗菌药物对检测的肠杆菌科细菌具有很好的体外抗菌活性,但对非发酵菌的体外抗菌活性较差。     

1998-2005年我院临床分离非发酵革兰阴性杆菌耐药性分析

目的了解1998—2005年我院临床分离非发酵革兰阴性杆菌的分布和耐药性。方法MicroScan WalkAway-40全自动微生物鉴定和药敏系统从我院临床标本中分离的12700株非发酵革兰阴性杆菌进行鉴定和药敏试验。结果非发酵革兰阴性杆菌前4位依次是铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽窄食单胞菌和洛菲不动杆菌。非发酵苇兰阴性杆菌对11种抗菌药的耐药率均呈上升趋势，尤其是铜绿假单胞菌对头孢他啶、头孢吡肟、亚胺培南、庆大霉索和妥布霉索，鲍曼不动杆菌对亚胺培南耐药率上升明显。洛菲不动杆菌耐药率仍很低。嗜麦芽窄食单胞菌对12种常用抗菌药物呈现多重耐药，除对环丙沙星和复方磺胺甲嗯唑耐药率较低外，其余均在42．9％～100％。结论铜绿假单胞菌、鲍曼不动杆菌和嗜麦芽窄食单胞菌足多重耐药且耐药率高的病原菌，应根据药敏试验结果选用抗菌药物。     

Ceftobiprole对糖尿病足感染病原菌的体外抗菌活性

糖尿病足感染(DFIs)是糖尿病患者的常见并发症。早期DFIs通常由金葡菌感染所致,20%因DFIs需住院的患者可分离出MRSA;较晚期DFIs患者可由需氧革兰阴性杆菌所致,其中45%还可分离到厌氧菌。ceftobiprole为新型广谱头孢菌素类抗生素,对金葡菌(包括MRSA和万古霉素中介金葡菌)、万古霉素耐药粪肠球菌属(氨苄西林耐药肠球菌除外)、其他革兰阳性菌以及除普通变形杆菌或产ESBLs的肠杆菌科细菌之外的许多革兰阴性杆菌具有抗菌活性,但对厌氧菌的抗菌活性资料较少。Goldstein等进行ceftobiprole对糖尿病足感染病原菌的抗菌活性试验。该试验收…     

In vitro activity of aztreonam in combination with newer beta-lactams and amikacin against multiply resistant gram-negative bacilli

The in vitro synergistic activity of aztreonam in combination with piperacillin, moxalactam, cefotaxime, cefoperazone, and amikacin was examined against multiply resistant isolates of the family Enterobacteriaceae and Pseudomonas aeruginosa. Aztreonam in combination with amikacin demonstrated synergy against 71% of the isolates, whereas combinations of aztreonam plus a second beta-lactam demonstrated synergy against 42% of the isolates.     

In vitro activity of ceftaroline against gram-positive and gram-negative pathogens isolated from patients in Canadian hospitals in 2009

The in vitro activities of ceftaroline and comparative agents were determined for a collection of the most frequently isolated bacterial pathogens from hospital-associated patients across Canada in 2009 as part of the ongoing CANWARD surveillance study. In total, 4,546 isolates from 15 sentinel Canadian hospital laboratories were tested using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. Compared with other cephalosporins, including ceftobiprole, cefepime, and ceftriaxone, ceftaroline exhibited the greatest potency against methicillin-susceptible Staphylococcus aureus (MSSA), with a MIC₉₀ of 0.25 μg/ml. Ceftaroline also demonstrated greater potency than ceftobiprole against community-associated methicillin-resistant S. aureus (MRSA) (MIC₉₀, 0.5 μg/ml) and health care-associated MRSA (MIC₉₀, 1 μg/ml) and was at least 4-fold more active than other cephalosporins against Staphylococcus epidermidis; all isolates of MSSA and MRSA tested were susceptible to ceftaroline (MIC, ≤1 μg/ml). Against streptococci, including Streptococcus pneumoniae, ceftaroline MICs (MIC₉₀, ≤0.03 μg/ml) were comparable to those of ceftobiprole; however, against penicillin-nonsusceptible, macrolide-nonsusceptible, and multidrug-nonsusceptible isolates of S. pneumoniae, ceftaroline demonstrated 2- to 4-fold and 4- to 16-fold more potent activities than those of ceftobiprole and ceftriaxone, respectively. All isolates of S. pneumoniae tested were susceptible to ceftaroline (MIC, ≤0.25 μg/ml). Among Gram-negative isolates, ceftaroline demonstrated potent activity (MIC₉₀, ≤0.5 μg/ml) against Escherichia coli (92.2% of isolates were susceptible), Klebsiella pneumoniae (94.1% of isolates were susceptible), Proteus mirabilis (97.7% of isolates were susceptible), and Haemophilus influenzae (100% of isolates were susceptible). Ceftaroline demonstrated less potent activity (MIC₉₀, ≥4 μg/ml) against Enterobacter spp., Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella oxytoca, Serratia marcescens, and Stenotrophomonas maltophilia. Overall, ceftaroline demonstrated potent in vitro activity against a recent collection of the most frequently encountered Gram-positive and Gram-negative isolates from patients attending hospitals across Canada in 2009.     

In vitro activity of moxifloxacin against 923 anaerobes isolated from human intra-abdominal infections

The in vitro activity of moxifloxacin against 923 recent anaerobic isolates obtained from pretreatment cultures in patients with complicated intra-abdominal infections was studied using the CLSI M11-A-6 agar dilution method. Moxifloxacin was active against 87% (96 of 110) Bacteroides fragilis strains at < or = 1 microg/ml and 87% (79 of 90) B. thetaiotaomicron strains at < or = 2 microg/ml. Species variation was seen, with B. uniformis, B. vulgatus, Clostridium clostridioforme, and C. symbiosum being least susceptible and accounting for most of the resistant isolates; excluding the aforementioned four resistant species, 86% (303 of 363) of Bacteroides species isolates and 94% (417 of 450) of all other genera and species were susceptible to < or = 2 microg/ml of moxifloxacin. Overall, moxifloxacin was active against 763 of 923 (83%) of strains at < or = 2 microg/ml, supporting its use as a monotherapy for some community-acquired intra-abdominal infections.     

In vitro activities of moxalactam and cefotaxime against aerobic gram-negative bacilli.

The in vitro activities of two new beta-lactam antibiotics, moxalactam disodium (LY 127935) and cefotaxime (HR-756), were compared with cefoxitin, cefamandole, cefuroxime, cephalothin, and, in some instances, carbenicillin, gentamicin, and amikacin against aerobic gram-negative bacilli. Test isolates included normally cephalosporin-resistant members of the Enterobacteriaceae and Pseudomonas spp. and a variety of nonfermentative or oxidase-positive bacteria. Both moxalactam and cefotaxime demonstrated impressive in vitro activities against both groups of microorganisms. The two new drugs were clearly more active than any of the other beta-lactam antibiotics against species of Escherichia, Citrobacter, Enterobacter, Klebsiella, Proteus, Providencia, Pseudomonas, and Serratia. An additive or synergistic effect could also be demonstrated with the majority of Pseudomonas and Serratia isolates when either moxalactam or defotaxime was combined with amikacin.     

In vitro interactions of amikacin and beta-lactam antibiotics against amikacin-resistant gram-negative bacilli

We tested 42 strains of amikacin-resistant gram-negative bacilli with amikacin in combination with six beta-lactam antibiotics using the checkerboard and time-kill curve techniques. Synergism was demonstrated with time-killing curve in 43-68% of the strains tested. Ceftazidime plus amikacin was the most active combination by the checkerboard technique, while amikacin-cefoperazone was the most active combination by the time-killing curve technique against Pseudomonas aeruginosa. Discrepancies were found between the results of the two methods used.     

痰标本分离革兰阴性杆菌整合子分布及分型研究

目的研究临床痰标本分离革兰阴性杆菌中整合子的分布与分型。方法用Ⅰ类、Ⅱ类和Ⅲ类3种整合酶基因通用引物扩增398株痰标本分离革兰阴性杆菌的相应基因;用琼脂对倍稀释法检测临床菌株的MIC。结果Ⅰ类整合酶基因总阳性率为48.7%,Ⅱ类整合酶基因总阳性率为2.3%,未检出Ⅲ类整合酶基因阳性菌株,Ⅰ类和Ⅱ类整合子同时阳性率为1.5%。肠杆菌科细菌Ⅰ类整合酶基因阳性率为69%,Ⅱ类整合子阳性率为2.7%;非发酵菌中Ⅰ类整合子阳性率为34%,Ⅱ类整合子阳性率为1.8%。在肠杆菌科细菌中,Ⅰ类整合酶基因阳性菌株对多种抗菌药物的耐药率均明显高于阴性菌株。结论在痰标本分离的革兰阴性杆菌中,肠杆菌科细菌Ⅰ类整合子的携带率高于非发酵菌,Ⅱ类整合子则无明显区别。     

重症监护病房革兰阴性杆菌耐药性监测与分析

目的了解重症监护病房（ICU）革兰阴性杆菌对临床常用抗菌药的耐药性变化，以指导合理选择抗菌药物。方法采用纸片扩散法对2003年1月-2004年12月我院ICU分离出的革兰阴性杆菌进行药敏检测，按NCCLS2003年版标准判断结果。结果2年中分离出245株革兰阴性杆菌，其中以不动杆菌（48．2％）和铜绿假单胞（11．0％）为主的非发酵菌占65．3％，74．5％来自痰液标本。亚胺培南的总敏感率最高（93．9％），对除嗜麦芽窄食单胞菌外的其他革兰阴性杆菌具有很好的抗菌活性；革兰阴性杆菌对头孢他啶、头孢哌酮-舒巴坦、头孢吡肟、哌拉西林-三唑巴坦和阿米卡星的敏感率多数为44％～68％，对其他抗菌药高度耐药；头孢他啶和复方磺胺甲嘿唑对嗜麦芽窄食单胞菌的敏感率高达73．3％。大肠埃希菌和肺炎克雷伯菌产ESBLs菌株分别占26．3％和32．3％；产酶菌株对多数常用抗菌药物耐药率高于非产酶菌株，对亚胺培南无耐药，头孢哌酮-舒巴坦和哌拉西林-三唑巴坦对产ESBLs菌株抗菌活性明显强于其他头孢菌素。结论非发酵菌在从ICU分离出的革兰阴性杆菌中占有较高比例，亚胺培南对除嗜麦芽窄食单胞菌外的其他革兰阴性杆菌具有较好的抗菌活性，其他抗菌药物抗菌活性较低。     

In vitro susceptibility to meropenem and other antimicrobial agents among gram-negative bacilli isolated from hospitalized patients in central India

BACKGROUND: Growing multiple drug resistance among gram-negative bacilli among hospitalized patients is a serious therapeutic problem, and the aim of the study was to assess the situation in our hospital. METHODS: Antimicrobial susceptibility testing with the disk method was carried out on 1,533 isolates of gram-negative bacilli from urine, pus, body fluid and blood from hospitalized patients. RESULTS: Seventeen percent of isolates were susceptible only to meropenem and either to piperacillin + tazobactam, to cefoperazone + sulbactam or to both. Eleven percent of isolates were susceptible only to meropenem and 6% were resistant to all antimicrobial agents including meropenem. CONCLUSION: Growing multiple drug resistance among gram-negative bacilli in hospital practice demands a rigid antibiotic policy and strict infection control measures.