老年人下呼吸道感染的细菌分布特点及耐药性分析

目的：了解老年人下呼吸道感染的病原菌分布情况及耐药性。方法：用VTTEK60(Bio merieux，法国)微生物全自动分析系统鉴定，对从痰培养中分离的910株细菌进行鉴定和药敏试验。结果：医院内老年人下呼吸道感染以革兰阴性杆菌为主，占86．0％(782株)，革兰阳性球菌占6．0％(55株)，真菌占8．0％(73株)。革兰阴性杆菌中肺炎克雷伯菌、铜绿假单胞菌、大肠埃希菌和不动杆菌占优势，分别为28．0％(255株)、13．3％(121株)、12．2％(111株)、7．9％(72株)，革兰阳性球菌中金黄色葡萄球菌占3．2％(29株)，真菌以白色念珠菌为优势5．6％(51株)。药敏结果显示肺炎克雷伯菌和大肠埃希菌对三代头孢菌素除头孢他啶外，其余的耐药率在30．6％以上，二代头孢菌素耐药率为47．0％～61．7％，一代头孢菌素耐药率高达53．8％～63．3％，大肠埃希菌对环丙沙星、氧氟沙星、氨苄西林、复方新诺明耐药率高达73．6％以上。亚胺培南、头孢他啶、头孢吡肟、头孢哌酮／舒巴坦对肺炎克雷伯菌和大肠埃希菌具有良好的抗菌活性。不动杆菌对头孢哌酮、头孢呋辛钠耐药率达49．3％～58．6％，对头孢唑啉、头孢克洛、头孢西丁、氨曲南、氨苄西林耐药率高达70．5％以上。亚胺培南、头孢他啶、头孢吡肟、阿米卡星、头孢哌酮／舒巴坦对铜绿假单胞菌抗菌活性较强，其余抗生素耐药率达38．8％～97．7％。结论：老年人下呼吸道感染的主要病原菌前5位是肺炎克雷伯菌、铜绿假单胞菌、大肠埃希菌、不动杆菌和白色念珠菌。亚胺培南、头孢他啶、头孢吡肟、阿米卡星、头孢哌酮／舒巴坦对革兰阴性杆菌保持较强的抗菌活性。     

呼吸道感染中革兰阴性杆菌分布及耐药性变迁

目的了解徐州医学院附属医院近5年住院患者呼吸道感染分离菌中革兰阴性杆菌的分布及耐药性的变化。方法收集该院2008至2012年住院呼吸道感染患者分离菌株,进行药敏试验并分析结果。结果呼吸道标本主要来源于ICU、神经科和呼吸科;5年内大肠埃希菌所占比率呈显著下降趋势,克雷伯菌属、不动杆菌属细菌逐年升高,铜绿假单胞菌略有降低。近3年嗜麦芽窄食单胞菌增多。革兰阴性杆菌对多黏菌素B敏感率保持在90．0％以上;大肠埃希菌对碳青霉烯类抗生素敏感率保持90．0％以上;碳青霉烯类抗生素对不动杆菌属和克雷伯菌属细菌的抗菌活性逐年下降;细菌对头孢菌素类的敏感性普遍降低,大肠埃希菌和克雷伯菌属细菌对头孢菌素类抗生素敏感率〈20．0％,对氨曲南的敏感率更低;而对阿米卡星的敏感性有所恢复。结论革兰阴性杆菌是呼吸道感染的重要病原菌,对临床常用抗菌药物敏感率下降值得重视,应加强对呼吸道病原菌耐药性监测和防控。     

小儿社区获得性肺炎临床常见革兰阴性杆菌的体外抗菌活性研究

目的对小儿社区获得性肺炎临床常见的革兰阴性杆菌的耐药性及体外抗菌活性进行分析研究。方法采用VITEK-32全自动微生物鉴定仪进行细菌鉴定和药敏试验，最小抑菌浓度（MIC）应用微量琼脂稀释法测定，超广谱β内酰胺酶（ESBLs）检测采用双纸片扩散法。结果小儿社区获得性肺炎深部痰标本1029例分离出的G杆菌中，分离率位于前5位的菌为肺炎克雷伯菌172株、大肠埃希菌163株、鲍曼不动杆菌71株、黏质沙雷菌70株，铜绿假单胞菌45株。15种抗菌药物对此5种革兰阴性杆菌的体外活性中，亚胺培南对肠杆菌科菌肺炎克雷伯菌、大肠埃希菌和黏质沙雷菌100．00％敏感，MIC50和MIC90均为4ug／ml。对非发酵菌鲍曼不动杆菌和铜绿假单胞菌敏感率为80．00％以上，MIC50和MIC90为4μg／ml和16μ／ml；β内酰胺类药物包括第三、四代头孢菌素的耐药率都相对较高，尤其第三代头孢曲松对黏质沙雷菌和铜绿假单胞菌的耐药率分别高达92．86％和100．00％；哌拉西林／他唑巴坦对5种G-杆菌的敏感率都较高，在80．00％～100．00％之间；其余抗生素在儿童应用很少，但也有一定的耐药性。主要产ESBLs的菌株肺炎克雷伯菌和大肠埃希菌ESBLs的发生率分别为42．44％和53．99％。结论小儿社区获得性肺炎标本中分离的各种G杆菌的耐药性均不尽相同，对本地区常见细菌的耐药性进行监测具有重要意义。     

普外科手术患者常见病原菌及耐药性分析

目的了解我院普外科病原菌的菌种构成及对抗菌药物的耐药性,为预防性应用抗菌药物和术后抗感染治疗提供依据。方法采用ATB Expression自动细菌培养鉴定仪及配套板条对普外科分离的菌株进行鉴定及药敏试验,用WHONET 5.6软件进行统计学分析。结果普外科分离病原菌以革兰阴性杆菌为主,占83.3%。前四位病原菌依次是大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和金黄色葡萄球菌。大肠埃希菌对一些常用抗菌药物如头孢菌素有一定的耐药性,对第三代头孢菌素和第Ⅱ代头孢菌素的耐药率也在47.2%-77.5%之间。葡萄球菌对青霉素和红霉素等表现出较高的耐药性,但对万古霉素仍然非常敏感。结论普外科的病原菌构成以革兰阴性杆菌占主导地位,临床在抗感染治疗时应根据药敏试验合理应用并及时调整抗菌药物。     

某院革兰阴性杆菌耐药性监测及其临床意义

目的 分析该院2010年度临床分离革兰阴性杆菌的耐药状况,为临床合理使用抗菌药物提供依据.方法 常规方法培养分离医院内感染病原菌,并应用全自动细菌鉴定分析仪鉴定到种,采用WHONET5.4软件进行数据统计分析.结果 该院共分离出革兰阴性杆菌445株,其中大肠埃希菌111株,铜绿假单胞菌109株,鲍曼不动杆菌84株,肺炎克雷伯菌69株.药敏监测结果显示,大肠埃希菌和肺炎克雷伯菌对哌拉西林和氨苄西林耐药,对美罗培南、亚胺培南、厄他培南、替加环素敏感.铜绿假单胞菌对头孢替坦、复方新诺明、氨苄西林耐药,对阿米阿星和他唑巴坦较为敏感,鲍曼不动杆菌对头孢唑林、头孢西丁、头孢呋辛钠、呋喃妥因耐药,对美罗培南敏感.结论 革兰阴性杆菌对多种抗菌药物的耐药率呈现上升趋势,临床微生物实验室应加强对多重耐药菌的监测,为临床正确合理使用抗菌药物提供依据.     

头孢米诺的体外抗菌作用研究

目的评价头孢米诺对近期临床分离的肠杆菌科细菌、不发酵糖革兰阴性杆菌和厌氧菌的体外抗菌作用。方法采用琼脂稀释法测定头孢米诺对884株临床分离的大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和厌氧菌等的体外抗菌作用。结果 316株大肠埃希菌和肺炎克雷伯菌中不产酶株96株(30.4%),单产ESBLs菌173株(54.7%),单产AmpC酶菌6株(1.9%)和产ESBLs+AmpC酶菌41株(13.0%)。头孢米诺对上述大肠埃希菌和肺炎克雷伯菌中不产酶和单产ESBLs菌株,以及变形杆菌属和摩根菌属细菌均具有良好的抗菌活性,MIC50和MIC90值大多≤2 mg/L;抗菌活性优于头孢美唑和头孢西丁;头孢米诺对不产酶大肠埃希菌和肺炎克雷伯菌的抗菌活性亦优于测试的头孢硫脒、头孢呋辛、头孢哌酮-舒巴坦和哌拉西林-他唑巴坦2种酶抑制剂复方,但抗菌活性均不及亚胺培南和美罗培南。头孢米诺对大肠埃希菌和肺炎克雷伯菌中产AmpC酶菌株的抗菌活性和肠杆菌属、沙雷菌属、枸橼酸杆菌属细菌和铜绿假单胞菌、鲍曼不动杆菌等不发酵糖革兰阴性杆菌的抗菌活性差;但头孢米诺对梭杆菌属细菌有高度抗菌活性,MIC50和MIC90分别为≤0.06 mg/L和1 mg/L,对其他受试的厌氧菌亦具有良好的抗菌活性。结论头孢米诺对不产酶和单产ESBLs的大肠埃希菌和肺炎克雷伯菌,以及变形杆菌属细菌、摩根摩根菌和厌氧菌等均具有良好的抗菌活性。提示头孢米诺可用于上述敏感菌以及厌氧菌所致感染的治疗。     

头孢米诺等抗菌药物对大肠埃希菌、肺炎克雷伯菌及拟杆菌属的体外抗菌活性

目的 比较头孢米诺等抗菌药物对临床分离大肠埃希菌、肺炎克雷伯菌、拟杆菌属的体外抗菌活性.方法 琼脂稀释法测定16种抗菌药物对来自全国15家教学医院的945株大肠埃希菌和588株肺炎克雷伯菌的MIC值以及4种抗菌药物对50株拟杆菌属的MIC值.WHONET 5.4软件进行药敏数据统计分析.结果 1 533株大肠埃希菌和肺炎克雷伯菌中,不产超广谱β内酰胺酶(extended spectrum beta lactamases,ESBLs)和AmpC 628株,837株仅产ESBLs,68株产AmpC.头孢米诺对不产ESBLs或单产ESBLs的大肠埃希菌和肺炎克雷伯菌敏感率均高于90%,其MIC50较头孢美唑低2～4倍,较头孢西丁低8～16倍;MIC90较头孢美唑低2～8倍,较头孢西丁低8～16倍.对单产ESBLs的菌株,头孢米诺体外抗菌活性优于第三、四代头孢菌素、头孢哌酮/舒巴坦、氨曲南、左氧氟沙星和阿米卡星,劣于碳青霉烯类药物,活性与哌拉丙林/三唑巴坦相仿.但对产AmpC的菌株,头孢米诺的敏感率低于20%.头孢米诺对拟杆菌属的敏感率为90%,高于头孢美唑(50%～70%)和青霉素(0%),活性与甲硝唑相仿.结论 头孢米诺对产ESBLs及非产ESBLs的大肠埃希菌和肺炎克雷伯菌以及拟杆菌属有良好的体外抗菌活性,提示头孢米诺可为临床治疗此类菌株感染提供一种选择.     

424例痰培养病原菌菌谱和耐药性分析

目的监测痰标本的病原菌菌谱及其耐药性,为临床经验用药和医院感染控制提供依据。方法对424例痰培养阳性标本的鉴定结果和药敏试验结果进行回顾性分析。结果 424例痰培养病原菌主要为革兰阴性杆菌(81.8%),病原菌前5位依次为肺炎克雷伯菌、副流感嗜血杆菌、铜绿假单胞菌、大肠埃希菌和金黄色葡萄球菌。革兰阴性杆菌对氨苄西林耐药率达92.3%,铜绿假单胞菌、鲍曼复合醋酸钙不动杆菌对1、2代头孢菌素,头孢西丁,呋喃妥因等抗菌药物的耐药率在80%～100%,葡萄球菌属对青霉素G耐药率为93.4%。结论痰标本病原菌仍以革兰阴性杆菌为主,且对常用抗菌药物的耐药性均较高。     

某医院临床分离革兰阴性杆菌种类分布及耐药性监测

目的了解医院病原学标本检测革兰阴性杆菌种类分布及耐药情况,为加强防控措施提供依据。方法采用细菌培养鉴定技术和药敏试验方法,对某医院临床分离革兰阴性菌感染分布进行调查与分析。结果调查期间从该医院临床送检标本中分离病原菌3 905株,革兰阴性杆菌占62.0%。居前5位的依次为大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、鲍曼不动杆菌和阴沟肠杆菌。大肠埃希菌和肺炎克雷伯菌中产超广谱β-内酰胺酶菌株检出率分别为43.5%和34.0%,革兰阴性杆菌对亚胺培南和丁胺卡那较敏感,耐药率均50%。结论该医院临床标本检出革兰阴性杆菌主要优势菌为5种,普遍产生严重的耐药性,仅对少数抗菌药物敏感。     

头孢米诺等抗菌药物对大肠埃希菌、肺炎克雷伯菌及拟杆菌属的体外抗菌活性

目的 比较头孢米诺等抗菌药物对临床分离大肠埃希菌、肺炎克雷伯菌、拟杆菌属的体外抗菌活性.方法 琼脂稀释法测定16种抗菌药物对来自全国15家教学医院的945株大肠埃希菌和588株肺炎克雷伯菌的MIC值以及4种抗菌药物对50株拟杆菌属的MIC值.WHONET 5.4软件进行药敏数据统计分析.结果 1 533株大肠埃希菌和肺炎克雷伯菌中,不产超广谱β内酰胺酶(extended spectrum beta lactamases,ESBLs)和AmpC 628株,837株仅产ESBLs,68株产AmpC.头孢米诺对不产ESBLs或单产ESBLs的大肠埃希菌和肺炎克雷伯菌敏感率均高于90%,其MIC_(50)较头孢美唑低2～4倍,较头孢西丁低8～16倍;MIC90较头孢美唑低2～8倍,较头孢西丁低8～16倍.对单产ESBLs的菌株,头孢米诺体外抗菌活性优于第三、四代头孢菌素、头孢哌酮/舒巴坦、氨曲南、左氧氟沙星和阿米卡星,劣于碳青霉烯类药物,活性与哌拉丙林/三唑巴坦相仿.但对产AmpC的菌株,头孢米诺的敏感率低于20%.头孢米诺对拟杆菌属的敏感率为90%,高于头孢美唑(50%～70%)和青霉素(0%),活性与甲硝唑相仿.结论 头孢米诺对产ESBLs及非产ESBLs的大肠埃希菌和肺炎克雷伯菌以及拟杆菌属有良好的体外抗菌活性,提示头孢米诺可为临床治疗此类菌株感染提供一种选择.     

Comparative Study of the In Vitro Antibacterial Activity of Cefoxitin, Cefuroxime, and Cephaloridine

The in vitro antibacterial effects of cefoxitin, a semisynthetic cephamycin, cefuroxime, a new cephalosporin antibiotic, and cephaloridine were compared. With gram-positive bacteria, marked differences were found only in the effects against Streptococcus faecalis, where cephaloridine and cefuroxime were superior to cefoxitin. With gram-negative aerobic bacteria, cefoxitin, which is known to be more resistant to beta-lactamases from gram-negative bacteria than any cephalosporin, was found to be more effective than cefuroxime and cephaloridine against ampicillin-resistant strains of Escherichia coli and indole-positive strains of Proteus. Haemophilus influenzae was found to be more susceptible to cefuroxime than to cefoxitin and cephaloridine. When ampicillin-resistant strains of H. influenzae were tested, markedly higher minimal inhibitory concentration values were obtained with cephaloridine in comparison to those obtained with ampicillin-susceptible strains. These increases in the minimal inhibitory concentration values were not observed with cefoxitin and cefuroxime, probably due to the resistance of these two compounds to beta-lactamases. Strains of Bacteroides fragilis were found to be much more susceptible to cefoxitin than to cefuroxime, which in turn was superior to cephaloridine. The results obtained indicate that cefoxitin and cefuroxime both are superior in their antibacterial spectra to the cephalosporins that are now in clinical use.     

Comparative activity of cefoxitin, ampicillin/sulbactam, and imipenem against clinical isolates of Escherichia coli and Klebsiella pneumoniae

The in vitro activities of cefoxitin, ampicillin/sulbactam, and imipenem were determined by the standard twofold agar dilution method against 62 strains of Escherichia coli and 40 strains of Klebsiella pneumoniae isolated from patients in intensive care units. Judging from the concentrations required to inhibit at least 90% of the test isolates, imipenem (MIC90 less than or equal to 0.125 micrograms/ml) was markedly more active than cefoxitin (MIC90 = 4 micrograms/ml) and ampicillin/sulbactam (MIC90 = 32 micrograms/ml) against both bacterial genera. Cefoxitin, therefore, was more active than ampicillin/sulbactam against these organisms. Breakpoints specified in the prescribing information are less than or equal to 4 micrograms/ml for imipenem, less than or equal to 16 micrograms/ml for cefoxitin, and less than or equal to 8 micrograms/ml for ampicillin/sulbactam. At these breakpoints all organisms were susceptible to imipenem and cefoxitin, while 73% of E coli and 78% of K pneumoniae were susceptible to ampicillin/sulbactam. At recommended susceptible MIC breakpoints of the National Committee for Clinical Laboratory Standards (less than or equal to 4 micrograms/ml for imipenem, less than or equal to 8 micrograms/ml for cefoxitin, and less than or equal to 4 micrograms/ml for ampicillin/sulbactam) all the isolates tested were susceptible to imipenem, while 98% and 73% of the E coli isolates were susceptible to cefoxitin and ampicillin/sulbactam, respectively, and 100% and 78% of the K pneumoniae isolates were susceptible to cefoxitin and ampicillin/sulbactam, respectively. Approximately 14% of E coli and 17% of K pneumoniae isolates were resistant to ampicillin/sulbactam (MIC greater than or equal to 32/16 micrograms/ml).     

Cefoxitin, a Semisynthetic Cephamycin Antibiotic: Susceptibility Studies

Cefoxitin, 3-carbamoyloxymethyl-7-alpha-methoxy-7-[2-(2-thienyl)acetamido]-3-cephem-4- carboxylic acid, is a new semisynthetic cephamycin with broad antibacterial activity. It is highly active against gram-negative microorganisms including indole-positive Proteus and Serratia strains, which are ordinarily reistant to the cephalosporins. Cefoxitin is also highly active against many strains of Escherichia coli and Proteus mirabilis which are resistant to the cephalosporins. Furthermore, E. coli and Klebsiella strains which are susceptible to the cephalosporins are generally more susceptible to the cephamycin analog. The susceptibility of the gram-positive bacteria falls well within the effective range of the antibiotic for gram-negative organisms, but cefoxitin is less active than cephalothin or cephaloridine. As is the case with the cephalosporins, strains of Pseudomonas and group D streptococci are resistant to cefoxitin. Changes in pH, inoculum density, and growth medium have no significant effect on the activity of the antibiotic.     

Use of cephalosporins for prophylaxis and therapy of polymicrobial infection in mice.

Cefoxitin, cefotetan, and cefmetazole were compared in 10-day therapy of intra-abdominal and subcutaneous infections caused by three organisms: Bacteroides fragilis and Bacteroides thetaiotaomicron combined with either Escherichia coli or Staphylococcus aureus. Intra-abdominal infection was caused by B. fragilis plus B. thetaiotaomicron plus E. coli. Therapy was initiated immediately before inoculation or was delayed for 8 h. Mortality was 14 of 30 (47%) for saline-treated mice, and all survivors developed abscesses. Immediate therapy reduced mortality and the percentage of mice with abscesses (in survivors), respectively, to 17 and 20% with cefoxitin, 0 and 13% with cefotetan, and 0 and 17% with cefmetazole, and the numbers of all bacteria were reduced by all the cephalosporins. Delayed therapy reduced mortality and abscess formation, respectively, to 20 and 8% of mice with cefoxitin, 10 and 93% with cefotetan, and 7 and 96% with cefmetazole. B. thetaiotaomicron survived in all abscesses treated with cefotetan and cefmetazole. Subcutaneous abscesses were caused by each organism alone or in combinations of one aerobe (S. aureus or E. coli) and one or two Bacteroides species. Early therapy reduced the numbers of all bacteria independent of their in vitro susceptibility. All agents reduced the number of each Bacteroides species with either E. coli or S. aureus. However, when therapy was delayed, cefotetan and cefmetazole were less effective than cefoxitin against B. thetaiotaomicron. Cefotetan was the most active agent against E. coli, and cefmetazole was the most effective against S. aureus. These data illustrate the efficacy of all tested cephalosporins in the prophylaxis of polymicrobial infections.     

In vitro activity of CP-65,207, a new penem antimicrobial agent, in comparison with those of other agents.

CP-65,207 is a new parenteral penem antibiotic with a broad spectrum that includes gram-positive, gram-negative, and anaerobic microorganisms, with MICs for 90% (MIC90s) of the majority of 1,101 clinical pathogens tested being less than or equal to 1 microgram/ml. The compound was from 10- to 100-fold more active than cefoxitin and broad-spectrum cephalosporins against gram-positive bacteria and anaerobes. CP-65,207 was less active than imipenem for staphylococci, group A streptococci, and Enterococcus faecalis. Against members of the family Enterobacteriaceae, CP-65,207 was in general 100-fold more active than cefoxitin, 5- to 10-fold more active than broad-spectrum cephalosporins, and 2-fold more active than imipenem. Fresh clinical isolates that were resistant to broad-spectrum cephalosporins were highly susceptible to CP-65,207 and imipenem (MIC90, 1 microgram/ml). Isolates of Enterococcus faecalis, Serratia marcescens, and anaerobic Peptococcus spp. had MIC90s of 8, 2, and 3.12 micrograms/ml, respectively. CP-65,207 was not very active against methicillin-resistant staphylococci or Pseudomonas aeruginosa. Killing kinetics showed that against some strains CP-65,207 is rapidly bactericidal at concentrations well below those required to achieve a similar degree of killing with cefotaxime, ceftazidime, and ceftriaxone. CP-65,207 was only slightly susceptible to hydrolysis by type I cephalosporinases and TEM-1, SHV-1, and PSE-2 plasmid-encoded enzymes. It had the highest affinity for penicillin-binding proteins 2, 1A, 1B, and 3 in cell-free preparations of Escherichia coli W-7.     

In Vitro Comparison of Cefoxitin, Cefamandole, Cephalexin, and Cephalothin

The in vitro effect of cefoxitin, cefamandole, cephalexin, and cephalothin was tested against 645 strains of bacteria recently isolated from clinical sources. Against gram-positive organisms cephalothin and cefamandole were the most effective, generally being three- to fourfold more active than cephalexin or cefoxitin. Enterococci were not inhibited by less than 25 μg of any of the antibiotics per ml. Against Enterobacteriaceae, cefoxitin and cefamandole were the most active. An exception was the Enterobacter strains, against which cefoxitin was the least effective. None of the Pseudomonas aeruginosa strains were susceptible to 100 μg of any of the cephalosporins per ml. Cefamandole was the most active agent against Neisseria meningitidis and Neisseria gonorrhoeae. It was also the most effective agent against Haemophilus influenzae, even when taking into account a threefold inoculum effect.     

大肠埃希菌感染的临床分布与耐药性分析

目的分析大肠埃希菌在临床感染中的分布与耐药情况,为其在院内、外感染控制以及临床合理用药方面提供科学依据。方法分析2010年1月至2014年12月5年间该院临床各类标本中大肠埃希菌的分离情况并分析大肠埃希菌的科室分布及其耐药情况。结果分离的2 405株大肠埃希菌主要来源于尿液1 049株(43.60%)及痰液562株(23.4%);其中产超广谱β-内酰胺酶(ESBLs)大肠埃希菌的检出率为57.92%;大肠埃希菌对青霉素类、头孢菌素类、氟喹诺酮类、氨基糖苷类和磺胺类等的大多数抗菌药物的耐药率大于50%;耐药率小于10%的抗菌药物有亚胺培南(0)、美罗培南(0)、哌拉西林/他唑巴坦(4.6%)、头孢哌酮/舒巴坦(6.4%)和头孢西丁(7.7%),对头孢曲松、头孢噻肟、头孢吡肟等部分第3、4代头孢菌素的耐药性有明显增加趋势。结论大肠埃希菌在医院获得性感染中存在比较严重的耐药情况,临床应加强对病原菌的分布及耐药性检测,避免产生更多的耐药菌株,以降低细菌的耐药性及医院的感染率。     

Antibacterial activities of SM-1652 compared with those of other broad-spectrum cephalosporins.

The in vitro and in vivo activities of Sm-1652 were compared with those of other cephalosporins. SM-1652 possessed a wide antibacterial spectrum which included activity against Pseudomonas aeruginosa. It also exhibited potent antibacterial activities against gram-positive cocci and clinical isolates of glucose nonfermentative bacteria. Most notably, its activity against glucose nonfermentative bacteria was the highest of all of the drugs tested. The bactericidal activity of SM-1652 was compared with that of cefoperazone. The difference between the minimum bactericidal concentration and the minimum inhibitory concentration of SM-1652 was actually smaller than that of cefoperazone for Escherichia coli and clinical isolates of indole-positive Proteus spp. SM-1652 was stable for most cephalosporinases but was hydrolyzed to some extent by penicillinases. The in vivo therapeutic effect of SM-1652 against infections in mice was better than those of cefazolin and cefoxitin. The in vivo antipseudomonal activity of SM-1652 was second to that of cefsulodin.