头孢硫脒与6种抗菌药物对革兰氏阳性球菌的联合药敏研究

评价头孢硫脒分别与万古霉素、奈替米星、阿米卡星、环丙沙星、左氧氟沙星和加替沙星等 6种抗菌药物联合用药 ,对于临床分离的革兰氏阳性球菌 ,包括金黄色葡萄球菌 (Staphylococcusaureus ,SA )、表皮葡萄球菌 (Staphylococcusepidermidis ,SE)和粪肠球菌 (Enterococcusfaecalis ,EF)的体外联合抗菌效应。采用棋盘法设计 ,微量肉汤稀释法测定。测定不同浓度组合的六组抗菌药物对 90株临床分离的革兰氏阳性球菌的最低抑菌浓度 ,并计算FIC指数判定联合效应。FIC≤ 0 5为协同作用 ,0 5 2为拮抗作用。头孢硫脒与万古霉素、奈替米星、阿米卡星、环丙沙星、左氧氟沙星、加替沙星联合应用后 ,其MIC50 显著降低。FIC指数分布 :FIC≤ 0 5占 60 %～ 90 % ;0 5 2为 0。结果表明 6种抗菌药物与头孢硫脒联合用药后 ,对革兰氏阳性球菌基本表现为协同作用和相加作用 ,并以协同作用为主 ,无关作用较少 ,无拮抗作用。     

头孢硫脒与6种抗菌药物联用对金葡球菌的体外抗菌活性

目的:评价头孢硫脒分别与万古霉素、奈替米星、阿米卡星、环丙沙星、左氧氟沙星和加替沙星6种抗菌药物联合用药,对于临床分离的金葡球菌(SA)的体外联合抗菌效应.方法:经VITEK鉴定临床分离致病菌,采用棋盘法设计,微量肉汤稀释法测定6组抗菌药物对SA及耐甲氧西林金葡球菌(MRSA)的最低抑菌浓度,并计算部分抑菌指数(FIC指数). 结果:头孢硫脒与万古霉素、奈替米星、阿米卡星、环丙沙星、左氧氟沙星、加替沙星联合应用后,MIC50,MIC90明显降低,FIC指数<0.5占60%～90%,0.5～1占10%～30%,1～2占0～13.3%,>2为0.结论:头孢硫脒与6种抗菌药物联合应用后,对SA基本表现为协同和相加作用,说明联合用药的疗效要高于两药单独使用.     

大蒜素联合头孢唑林或苯唑西林对葡萄球菌的抗菌作用

目的：评价大蒜素分别与头孢唑林或苯唑西林联合用药,对于临床分离的革兰阳性球菌,包括金黄色葡萄球菌（staphylococcus aureus）和表皮葡萄球菌（staphylococcus epidermidis）的体外联合抗菌效应.方法：采用棋盘法设计,微量肉汤稀释法测定.测定不同浓度组合的二组抗菌药物对40株临床分离的革兰阳性球菌的最低抑菌浓度,并计算FIC指数,也称部分抑菌浓度（Fractiona inhibitory concentration index）判定联合效应.FIC≤0.5 为协同作用,0.5＜FIC≤1为相加作用,1＜FIC≤2为无关作用,FIC＞2为拮抗作用.结果：大蒜素与头孢唑林或苯唑西林联合应用后,其MIC50显著降低.FIC指数分布：FIC≤0.5占55%～75%;0.5＜FIC≤1占20%～40%;1＜FIC≤2占0～5.88%;FIC＞2为0.结论：头孢唑林或苯唑西林这2种抗菌药物与大蒜素联合用药后,对革兰阳性球菌基本表现为协同作用和相加作用.     

头孢硫脒与加替沙星对革兰阳性球菌的联合药敏研究

目的:评价头孢硫脒与加替沙星联合用药,对临床分离的G 球菌的体外联合抗菌效应.方法:采用棋盘法设计,微量肉汤稀释法测定头孢硫脒与加替沙星对90株临床分离的G 球菌的MIC,并计算FIC指数判定联合效应.结果:头孢硫脒与加替沙星联合应用后,其MIC50显著降低.FIC指数分布:FIC≤0.5占60%～86.7%;0.5＜FIC≤1占13.3%～26.7%;1＜FIC≤2占0～13.3%;FIC＞2为0.结论:加替沙星与头孢硫脒联合用药后,对G 球菌主要表现为协同作用和相加作用,并以协同作用为主,无关作用较少,无拮抗作用.     

69株革兰阳性球菌对抗菌药物的体外敏感度测定

目的了解抗菌药物对临床常见革兰阳性球菌的体外抗菌活性。方法采用K B法对临床分离得到的69株革兰阳性球菌进行药物敏感性测定。结果革兰阳性球菌对万古霉素的敏感率为100.0%，表皮葡萄球菌对头孢硫脒的敏感率为89.7%，对头孢唑林为84.4%;金黄色葡萄球菌对头孢硫脒的敏感率为95.0%，对头孢唑林为93.5%。肠球菌对头孢硫脒和头孢唑林的敏感率均为50%。结论头孢硫脒对革兰阳性球菌的抗菌活性优于头孢唑林、红霉素、阿奇霉素，仅次于万古霉素。头孢硫脒与头孢唑林对肠球菌的抗菌活性基本相同。     

国产头孢硫脒对224株凝固酶阴性葡萄球菌的体外抗菌活性研究

目的观察头孢硫脒对表皮葡萄球菌、溶血葡萄球菌等凝固酶阴性葡萄球菌的体外抗菌活性。方法采用琼脂稀释法对头孢硫脒进行224株表皮葡萄球菌、溶血葡萄球菌等凝固酶阴性葡萄球菌的最低抑菌浓度(MIC)测定。结果头孢硫脒对100株耐甲氧西林的凝固酶阴性葡萄球菌和124株甲氧西林敏感的凝固酶阴性葡萄球菌的MIC50,MIC90分别为0．5、128、≤0．125和2μg／ml。对甲氧西林敏感的表皮葡萄球菌(MSSE)、溶血葡萄球菌(MSSH)和里昂葡萄球菌(MSSL)的MIC90分别为0．5、2．0和2．0μg／ml。结论头孢硫脒对124株甲氧西林敏感的凝固酶阴性葡萄球菌具有较强的抑菌力。     

磷霉素与万古霉素对90株革兰阳性球菌的联合药敏研究

目的评价磷霉素与万古霉素对90株革兰阳性球菌30株粪肠球菌(Enterococcus faecalis,Ef)、30株金黄色葡萄球菌(Staphylococcus aureus,SA)、30株表皮葡萄球菌(Staphylococcus epidermidis,SE)的体外联合抗菌效应.方法采用棋盘法设计,微量肉汤稀释法测定.测定不同浓度组合的抗菌药物对90株临床分离的革兰阳性球菌的最低抑菌浓度,并计算FIC指数判定联合效应.FIC≤0.5为协同作用,0.5＜FIC≤1为相加作用,1＜FIC≤2为无关作用,FIC＞2为拮抗作用.结果磷霉素与万古霉素联合应用后,其MIC50显著降低.FIC指数分布FIC≤0.5占60%～93.3%;0.5＜FIC≤1占6.7%～40%;1＜FIC≤2占0;FIC＞2为0.结论磷霉素与万古霉素联合用药后,对革兰阳性球菌基本表现为协同作用和相加作用,并以协同作用为主,无关作用较少,无拮抗作用.     

磷霉素与万古霉素对90株革兰阳性球菌的联合药敏研究

目的:评价磷霉素与万古霉素对90株革兰阳性球菌:30株粪肠球菌(Enterococcus faecalis,Ef)、30株金黄色葡萄球菌(Staphylococcus aureus,SA)、30株表皮葡萄球菌(Staphylococcus epidermidis,SE)的体外联合抗菌效应.方法:采用棋盘法设计,微量肉汤稀释法测定.测定不同浓度组合的抗菌药物对90株临床分离的革兰阳性球菌的最低抑菌浓度,并计算FIC指数判定联合效应.FIC≤0.5为协同作用,0.5＜FIC≤1为相加作用,1＜FIC≤2为无关作用,FIC＞2为拮抗作用.结果:磷霉素与万古霉素联合应用后,其MIC50显著降低.FIC指数分布:FIC≤0.5占60%～93.3%;0.5＜FIC≤1占6.7%～40%;1＜FIC≤2占0;FIC＞2为0.结论:磷霉素与万古霉素联合用药后,对革兰阳性球菌基本表现为协同作用和相加作用,并以协同作用为主,无关作用较少,无拮抗作用.     

头孢硫脒与奈替米星对90株革兰阳性球菌联合药敏研究

目的评价头孢硫脒与奈替米星对90株G+球菌体外联合抗菌效应.方法采用棋盘法设计,微量肉汤稀释法测定.测定不同浓度组合的三组抗菌药物对90株临床分离的G+球菌的最低抑菌浓度,并计算FIC指数.结果头孢硫脒对金黄色葡萄球菌、表皮葡萄球菌、粪肠球菌的MIC50分别为16mg/L、1mg/L、2mg/L,与奈替米星联合应用后,其MIC50分别显著的降低至0.5mg/L、0.125mg/L、0.25mg/L.FIC指数结果表明头孢硫脒与奈替米星抗菌药物联合应用,对金黄色葡萄球菌、表皮葡萄球菌、粪肠球菌多数呈协同和相加作用,并以协同作用为主(66.7%～90%),无关作用较少(0～6.6%),无拮抗作用.结论头孢硫脒与奈替米星联合应用对90株G+球菌呈基本协同或相加作用.     

头孢硫脒与奈替米星对90株革兰阳性球菌联合药敏研究

目的:评价头孢硫脒与奈替米星对90株G+球菌体外联合抗菌效应.方法:采用棋盘法设计,微量肉汤稀释法测定.测定不同浓度组合的三组抗菌药物对90株临床分离的G+球菌的最低抑菌浓度,并计算FIC指数.结果:头孢硫脒对金黄色葡萄球菌、表皮葡萄球菌、粪肠球菌的MIC50分别为16mg/L、1mg/L、2mg/L,与奈替米星联合应用后,其MIC50分别显著的降低至0.5mg/L、0.125mg/L、0.25mg/L.FIC指数结果表明头孢硫脒与奈替米星抗菌药物联合应用,对金黄色葡萄球菌、表皮葡萄球菌、粪肠球菌多数呈协同和相加作用,并以协同作用为主(66.7%～90%),无关作用较少(0～6.6%),无拮抗作用.结论:头孢硫脒与奈替米星联合应用对90株G+球菌呈基本协同或相加作用.     

左氧氟沙星与磷霉素联用对30株金黄色葡萄球菌的抗菌活性

目的 评价左氧氟沙星(喹诺酮类抗菌药)与磷霉素(合成抗菌药)联用对30株金黄色葡萄球菌的体外抗菌效应.方法 用棋盘法设计,微量肉汤稀释法测定不同浓度组合的抗菌药物对15株甲氧西林敏感的金黄色葡萄球菌(MSSA)和15株甲氧西林耐药的金黄色葡萄球菌(MRSA)的最低抑菌浓度,并计算部分抑菌浓度指数(FICI)判定联合效应.结果 左氧氟沙星与磷霉素联用后,其对金黄色葡萄球菌的MIC50显著降低,15株MSSA:HCI≤0.5占36.4%;0.52为0.15株MRSA:HCI≤0.5占81.8%;0.52为0.结论 体外左氧氟沙星与磷霉素联用对30株金黄色葡萄球菌主要为协同和相加作用.     

Activity of ACHN-490 against meticillin-resistant Staphylococcus aureus (MRSA) isolates from patients in US hospitals

The activity of ACHN-490 was evaluated against 493 meticillin-resistant Staphylococcus aureus (MRSA) isolates collected in 2009-2010 from 23 US hospitals. The MIC₅₀ and MIC₉₀ values (minimal inhibitory concentrations for 50% and 90% of the organisms, respectively) for ACHN-490 were 1 and 2 μg/mL compared with 8 and 32 μg/mL for amikacin, 0.5 and 1 μg/mL for gentamicin and 2 and >16 μg/mL for tobramycin. The gene encoding the aminoglycoside-modifying enzyme APH(2″)-Ia/AAC(6′)-Ie was present in 12% of the subset of 84 isolates examined by polymerase chain reaction (PCR), whilst the gene encoding ANT(4′)-Ia was present in 89% of isolates. ACHN-490 activity was not affected by either enzyme.     

司帕沙星与其他5种抗菌药体外抗菌活性比较研究

测定了司帕沙星对临床分离的１９９ 株致病菌的体外抗菌活性并与氧氟沙星、环丙沙星、头孢唑啉、头孢噻肟、阿米卡星的抗菌活性进行比较。司帕沙星对革兰阳性菌的ＭＩＣ９０为０．１２５～０．５ｍ ｇ／Ｌ,对金葡球菌、化脓链球菌的抑菌率均为１００％ ,强于氧氟沙星、环丙沙星;对革兰阴性菌也具有良好的体外抗菌活性,与氧氟沙星、环丙沙星相似。不同细菌接种量和不同浓度血清对其抗菌活性无明显影响,仅在ｐＨ５．０ 时抗菌活性略有下降     

Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--I. Gram-positive bacteria

As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, penicillins, and carbapenems. Changes in the bacterial susceptibility for CZOP were also evaluated with the resistance ratio calculated with breakpoint MIC. Sixteen species (2,363 strains) of Gram-positive bacteria were isolated from the clinical materials annually collected from 1996 to 2001, and consisted of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible Staphylococcus epidermidis (MSSE), methicillin-resistant Staphylococcus epidermidis (MRSE), Staphylococcus haemolyticus, Staphylococcus saprophyticus, Enterococcus faecalis, Enterococcus faecium, Enterococcus avium, Streptococcus pyogenes, Streptococcus agalactiae, penicillin-susceptible Streptococcus pneumoniae (PSSP), penicillin-intermediate resistant S. pneumoniae (PISP), penicillin-resistant S. pneumoniae (PRSP), Streptococcus milleri group and Peptostreptococcus spp. The antibacterial activity of CZOP either against MSSA or MSSE was preferable (MIC90: 2 or 0.5 micrograms/mL) and comparable to those of other cephems. CZOP was also effective on MRSE (MIC90: 16 micrograms/mL) but not on MRSA. CZOP and other cephems had low antibacterial activity against S. haemolyticus (MIC90: 64 micrograms/mL). The antibacterial activity of CZOP against S. saprophyticus was comparable to or higher than those of other cephems, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (32 vs 1-2 micrograms/mL). The antibacterial activity of CZOP against E. faecalis was comparable to that of cefpirome (CPR; MIC90: 16 micrograms/mL) and higher than those of other cephems. No antibacterial activity of CZOP against E. faecium and E. avium was observed, like other drugs. The antibacterial activity of CZOP against S. pyogenes was as potent as those of cefotiam and CPR (MIC90: < or = 0.063 microgram/mL), and, against S. agalactiae, was also preferable (MIC90: 0.125 microgram/mL). CZOP indicated preferable antibacterial activity either against PSSP, PISP, or PRSP (MIC90: 0.25, 1, or 2 micrograms/mL). The antibacterial activity of CZOP against S. milleri group was also preferable, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (4 vs 0.5 micrograms/mL). The antibacterial activity of CZOP against Peptostreptococcus spp. was preferable but weaker than those of cefazolin and cefmetazole. The resistance ratio estimated from breakpoint MIC of CZOP was 95.9% in MRSA, 93.5% in PRSP, 63.3% in PISP, 35.8% in S. haemolyticus, 27.9% in E. faecalis, and 13.3% MRSE. Those resistance ratios were comparable to those for cefepime (CFPM), but E. faecalis showed 91.2% for CFPM. The difference in the resistance ratio of E. faecalis demonstrated that CZOP successfully maintained its antibacterial activity against these species. In correlation of drug susceptibility, 40.3% of PRSP was not inhibited at breakpoint MIC either CZOP or CFPM while 69.2% at breakpoint MIC either CZOP or ceftazidime. In conclusion, the antibacterial activities of CZOP against the Gram-positive bacteria obtained from the 6-year duration study were consistent with the results from the studies performed until the new drug application approval. A decline in the sensitivities of S. saprophyticus, S. milleri group, PISP, and PRSP to CZOP, however, was suggested.     

Susceptibility patterns of coagulase-negative staphylococci to several newer antimicrobial agents in comparison with vancomycin and oxacillin

Coagulase-negative staphylococci (CoNS) have emerged as important nosocomial pathogens. CoNS resistance to meticillin and other semisynthetic penicillins is now common. Elevated vancomycin minimal inhibitory concentrations (MICs) have been reported and are associated with worse treatment outcomes. Several newer antibiotics have recently become available for the treatment of Gram-positive infections. The purpose of this study was to assess the in vitro activity of telavancin, daptomycin, linezolid and tigecycline in comparison with oxacillin and vancomycin against 653 non-duplicate clinical isolates of CoNS by the agar dilution method. The greatest variability in MIC was observed for oxacillin. Presence of the mecA gene conferred higher MICs for oxacillin but did not influence MICs to all other antibiotics tested. Telavancin tended to have MICs that were 1-2 dilutions lower than vancomycin. Daptomycin had good activity against all isolates. Staphylococcus haemolyticus, Staphylococcus hominis subsp. novobiosepticus, Staphylococcus saprophyticus, Staphylococcus schleiferi and Staphylococcus simulans were the most daptomycin-susceptible CoNS species tested. The validity of the agar dilution method for daptomycin was confirmed, with >90% isolates having MICs that were within 1 dilution of parallel Etest results. Within-species MIC variation was most restricted for linezolid and tigecycline, with the exception of Staphylococcus epidermidis and Staphylococcus haemolyticus that demonstrated higher overall MICs to tigecycline.     

Antimicrobial susceptibility of Gram-positive bacterial isolates from the Asia-Pacific region and an in vitro evaluation of the bactericidal activity of daptomycin, vancomycin, and teicoplanin: a SENTRY Program Report (2003-2004)

Medical centres in eight countries in the Asia-Pacific region provided 2391 isolates for the SENTRY Antimicrobial Surveillance Program during 2003-2004 to determine their susceptibility to several antimicrobial classes, including daptomycin. Daptomycin, vancomycin and teicoplanin minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined for 120 isolates of Staphylococcus aureus, which included wild-type (WT) methicillin-resistant S. aureus (MRSA) and strains with decreased susceptibility to vancomycin (hetero-vancomycin-intermediate S. aureus (hVISA)). Oxacillin-resistant staphylococcal isolates were much less susceptible to the other tested agents compared with oxacillin-susceptible strains. Vancomycin resistance was higher among Enterococcus faecium (10.3%) than Enterococcus faecalis (0.4%), and macrolide resistance was high both for beta-haemolytic (17.7%) and viridans group (48.7%) streptococci. Daptomycin (MIC for 90% of the organisms (MIC(90))=0.5-1mg/L) was two-fold more potent than vancomycin, with >99% susceptibility when tested against staphylococci. All tested isolates of E. faecalis (MIC(90)=2mg/L) and beta-haemolytic streptococci (MIC(90)=0.5mg/L) were susceptible to daptomycin. Daptomycin MIC and MBC values were slightly higher for the hVISA isolates compared with WT-MRSA, with MBC/MIC ratios of only 1-2 for both groups. The MBC/MIC ratio for vancomycin was often greater when tested against these strains, particularly hVISA. In contrast, teicoplanin MBC/MIC ratios were significantly higher, with many of the strains showing values consistent with tolerance (>or=32). Daptomycin was demonstrated to have excellent in vitro activity when tested against Gram-positive isolates collected from Asia-Pacific countries, including hVISA strains.     

Nosocomial infections due to methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci at a university hospital in Taiwan from 1991 to 2003: resistance trends, antibiotic usage and in vitro activities of newer antimicrobial agents

A rapid increase of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection (from 39% in 1991 to 75% in 2003) and vancomycin-resistant enterococci (VRE) (from 1.2% in 1996 to 6.1% in 2003) at a university hospital in Taiwan was found. The noticeable rise of MRSA and VRE was significantly correlated with the increased consumption of glycopeptides, beta-lactam-beta-lactamase inhibitor combinations, extended-spectrum cephalosporins, carbapenems and fluoroquinolones (Pearson's correlation coefficient, P < 0.05). Minimum inhibitory concentrations (MICs) of 100 non-duplicate blood isolates of MRSA (in 2003) and of 25 non-duplicate isolates of vancomycin-resistant Enterococcus faecalis and 172 vancomycin-resistant Enterococcus faecium (in 1996-2003) causing nosocomial infection recovered from various clinical specimens of patients treated at the hospital to nine antimicrobial agents were determined by the agar dilution method. All of these isolates were susceptible to linezolid and were inhibited by 0.5mg/L of tigecycline, and all MRSA isolates were inhibited by daptomycin 1mg/L, including two isolates of MRSA with heteroresistance to vancomycin. Daptomycin had two-fold better activity against vancomycin-resistant E. faecalis (MIC90, 2 mg/L) than against vancomycin-resistant E. faecium (MIC90, 4 mg/L). Decreased susceptibilities of vancomycin-resistant E. faecium and MRSA to quinupristin/dalfopristin (non-susceptibility 25% and 8%, respectively) were found. Telithromycin had poor activity against the isolates tested (MIC90, 8 mg/L). Linezolid, daptomycin and tigecycline may represent therapeutic options for infections caused by these resistant Gram-positive organisms.     

Synergy of fosfomycin with beta-lactam antibiotics against staphylococci and aerobic gram-negative bacilli

Fosfomycin inhibits bacterial cell wall synthesis at the initial stage. It can act synergistically with beta-lactams. The effect of the combination of fosfomycin and selected penicillins and cephalosporins against staphylococci, Pseudomonas aeruginosa, Pseudomonas cepacia and selected Gram-negative bacteria was determined. Synergy was determined by agar dilution and checkerboard titration methods; synergy was defined as an FIC index less than or equal to 0.5 and partial synergy greater than 0.5 to 0.75. Concentrations of drugs used were those that would be reached in man by intravenous and oral routes. Fosfomycin combined with nafcillin and with cefotaxime against staphylococci showed synergy for most isolates. For methicillin-resistant Staphylococcus aureus, synergy or partial synergy was found for 90% of isolates. Synergy was less frequently found with Staphylococcus epidermidis. The MICs for S. aureus were reduced from greater than or equal to 32 micrograms/ml to less than or equal to 1 microgram/ml. Fosfomycin was synergistic with ticarcillin, piperacillin, azlocillin, ceftazidime, aztreonam and imipenem against 31 to 61% of P. aeruginosa. MICs were reduced from greater than or equal to 128 micrograms/ml to 8-32 micrograms/ml, depending upon the agent. Although fosfomycin acted synergistically with azlocillin, piperacillin and ceftazidime against some P. cepacia, most often there was an indifferent interaction and MICs were in the resistant range, greater than or equal to 128 micrograms/ml. The interaction of fosfomycin and ampicillin was synergistic against a number of strains of Enterobacteriaceae, Proteus vulgaris and Providencia rettgeri, yielding MICs in an achievable range. The combination of fosfomycin with beta-lactams may be clinically useful in selected situations, particularly for methicillin-resistant staphylococci and beta-lactam-resistant P. aeruginosa.     

Surveillance of susceptibility of clinical isolates to cefmetazole between 2000 and 2002

The antibacterial activity of cefmetazole (CMZ) against clinical isolates from 15 medical institutions all over Japan was evaluated yearly for two years from June 2000 to March 2002 and compared with that of other parenteral beta-lactams, cefazolin (CEZ), cefotiam (CTM), sulbactam/cefoperazone (SBT/CPZ), and flomoxef (FMOX). In the first surveillance from June 2000 to March 2001, 575 isolates of 13 species were tested, and 548 isolates of the same 13 species were tested in the second surveillance from April 2001 to March 2002. In these surveillances spanning two years, the MIC90s of CMZ against the bacterial species tested hardly differed. Changes in percent resistance of each species to CMZ (MIC of CMZ > or = 32 micrograms/mL) were as follows: methicillin-susceptible Staphylococcus aureus (MSSA, 0%-->0%), methicillin-resistant Staphylococcus aureus (MRSA, 73%-->87%), Staphylococcus epidermidis (19%-->32%), other coagulase-negative Staphylococcus spp. (other CNS, 13%-->18%), Escherichia coli (4%-->1%), Klebsiella pneumoniae (3%-->4%), Klebsiella oxytoca (0%-->0%), Proteus mirabilis (2%-->2%), Proteus vulgaris (14%-->7%), Morganella morganii (7%-->0%), Providencia spp. (17%-->0%), Peptostreptococcus spp. (0%-->0%), Bacteroides fragilis (10%-->11%), and other Bacteroides spp. (79%-->88%). The change in percent resistance of MRSA, S. epidermidis, other CNS, and other Bacteroides spp. tended to increase. In addition, the percent resistance of B. fragilis was 10%. It is necessary to pay much attention to the trends observed in these species. Compared to other drugs tested, against MSSA, the activity of CMZ was inferior to that of CEZ, CTM, and FMOX and superior to that of SBT/CPZ. Against MRSA, S. epidermidis, and CNS, the tested drugs exhibited little activity. Against Gram-negative bacteria, the activity of CMZ was almost superior to that of CEZ and CTM, and inferior to that of FMOX. Against B. fragilis and other Bacteroides spp., the activity of CMZ was almost superior to that of CEZ and CTM, and comparable to or inferior to that of SBT/CPZ and FMOX. No remarkable changes in the activity of CMZ were observed in this study compared with studies conducted before CMZ was launched. This result suggests that CMZ still maintains potent activity.