In vitro anti-anaerobic activity of the cephalosporin derivative RWJ 54428, compared to seven other compounds

Agar dilution MIC was used to test the activity of RWJ 54428, a new cephalosporin derivative, compared to imipenem, meropenem, ceftriaxone, piperacillin, piperacillin–tazobactam, clindamycin and metronidazole against 363 anaerobes isolated from clinical specimens. RWJ 54428 had low MICs against most β -lactamase-negative Gram-negative rods, and all Gram-positive strains except Clostridium difficile . Imipenem and meropenem had the lowest MICs (MIC₅₀s of 0.125 mg/L and MIC₉₀s of 1.0 mg/L). Piperacillin–tazobactam, clindamycin and metronidazole were active against most strains, and ceftriaxone was active mainly against β -lactamase-negative organisms.     

Evaluation of in vitro activity of a new fluoroquinolone trovafloxacin (cp-99,219) compared with other anti-anaerobic antimicrobials against members of the Bacteroides fragilis group

The in vitro activity of a new fluoroquinolone, trovafloxacin (CP-99,219) was compared with that of ten other agents against 100 clinical isolates in the Bacteroides fragilis group. Trovafloxacin was the most active quinolone (MIC₉₀, 1 μg/ml) followed by sparfloxacin (MIC₉₀, 8 μg/ml), levofloxacin (MIC₉₀, 16 μg/ml) and ofloxacin (MIC₉₀, 32 μg/ml). Ciprofloxacin was the least active quinolone (MIC₉₀, 64 μg/ml). Metronidazole, chloramphenicol, imipenem and piperacillin/tazobactam, showed excellent activity with an MIC₉₀ of 1, 8, 0.25 and 16 μg/ml, respectively. Cefoxitin showed good activity and piperacillin was the least active compound. B. vulgatus and B. ovatus were the most resistant species to trovafloxacin among those of the B.fragilis group with an MIC₉₀ of 4 μg/ml while B. fragilis and B. thetaiotaomicron were the most susceptible (MIC₉₀, 1 μg/ml).     

奥硝唑治疗厌氧菌性盆腔感染的临床研究

目的探讨奥硝唑治疗厌氧菌引起的盆腔感染临床效果及安全性。方法选取2012年4月-2013年11月厌氧菌性盆腔感染患者160例,随机分为普通组和治疗组,每组各80例,普通组使用替硝唑氯化钠注射液静脉滴注,每次0.5g,每天两次,维持治疗7d,治疗组使用奥硝唑氯化钠注射液静脉滴注,用法同普通组,治疗后对比两组患者治疗效果、细菌清除率及不良反应发生率。结果普通组治愈65例,治愈率81.25%,治疗组治愈66例,治愈率82.50%,两组临床效果相近,差异无统计学意义;细菌清除率普通组为95.35%、治疗组为97.22%,两组临床效果相近,对比差异无统计学意义;治疗后不良反应发生率治疗组为3.75%、普通组为27.50%,两组对比差异有统计学意义(χ2=11.347,P<0.05)。结论针对厌氧菌引起的盆腔感染患者使用奥硝唑氯化钠注射液治疗临床效果显著确切,且安全性高,值得临床推广应用。     

12种药物对临床分离厌氧菌的体外抗菌活性测定

测定了１２种药物对临床分离的３０株厌氧菌和３株标准菌株的ＭＩＣ，确定甲哨唑和ｃｌａｒｉｔｈｒｏｍｙｃｉｎ对革兰氏阴性厌氧菌的抗菌活性最强，其ＭＩＣ为０．５～１μｇ／ｍｌ．其次为大环内酯９４１和国产ｃｌａｒｉｔｈｒｏｍｙｃｉｎ（４μｇ／ｍｌ）及林可霉素和红霉素（８μｇ／ｍｌ），它们对于革兰氏阳性厌氧菌（包括梭菌）及消化链球菌也有相当的活性，而环丙氟啶酸、依诺沙星、头孢克罗、环丙沙星等抗厌氧菌拟杆菌活性较低；其ＭＩＣ为１６～６４μｇ／ｍｌ。     

大骨节病病因研究新假说——产生硫酸软骨素CHS酶的厌氧菌是主要病因

在益都、永寿KBD患区水源中分出产CHS酶厌氧菌,并能引致小鼠关节软骨损害的基础上,近一步在新病例较多的天水、汉源作病因调查,并以骺板软骨发育变化为指征研究KBD成因、发现4患区水源均被粪便严重污染。厌氧菌占粪便菌群结构的9.9％,说明其存在的普遍性。厌氧菌进入鼠体18天后引起骺板细胞柱增殖层细胞成倍增长及坏死、消失等病理变化与人类KBD早期病变一致。“改水”去因后即无新病例出现,说明防治有效。综合三方面结果说明厌氧菌是KBD的主要病因。     

肛周脓肿细菌感染菌群分布研究

①目的探讨肛周脓肿厌氧与需氧茵的菌群分布。②方法选择31例肛周脓肿患，对其脓液中的厌氧茵和需氧菌进行培养鉴定。③结果肛周脓肿感染患中男27例，女4例；感染中共分离出51株细菌，其中厌氧菌30株，需氧菌21株。厌氧菌总检出率为96．8％，需氧菌总检出率为67．4％。单纯厌氧菌感染检出率为32．3％，单纯需氧菌检出率为32％。、厌氧和需氧菌混合感染捡出率为64．5％。在所分离出的30株厌氧菌中，脆弱类杆菌占80％，消化链球菌占13％，普通类杆菌和产黑色素类杆菌各占33％21株需氧菌中，大肠杆菌占71％，肺炎克雷伯菌、产气肠杆菌、阴沟肠杆菌各占9．5％。④结论肛周脓肿男性患病率高于女性；细菌感染菌群分布以脆弱类杆菌和大肠杆菌为主；感染类型以厌氧和需氧菌混合感染居多。     

不同年龄段妇女细菌性阴道病（BV）阳性率情况统计

目的探讨细菌性阴道病不同年龄段妇女阳性率情况。方法通过细菌性阴道病快速诊断试剂,对1044份病人标本进行检测。结果所有病人总阳性率为41％,〈30岁者阳性率为34％,31—40岁者阳性率为40％,41—50岁者阳性率为44％,〉50岁者阳性率为55％。结论妇女细菌性病的诊断、治疗意义重大。     

Sequential Changes in Luminal Microflora and Mucosal Cytokine Expression during Developing of Colitis in HLA-B27/β 2 -Microglobulin Transgenic Rats

Background: Transgenic rats expressing HLA-B27 and human β 2 -microglobulin (HLA-B27 rats) spontaneously develop chronic colitis resembling human inflammatory bowel disease. We investigated the sequential changes in the luminal bacterial flora and mucosal cytokine mRNA expression in this model. Methods: HLA-B27 rats were maintained in a specific pathogen-free environment, and luminal microflora was evaluated by standard bacterial culture technique. The expression of mucosal cytokine mRNA was analysed by RT-PCR methods. Results: Clinical symptoms of colitis appeared at 8 weeks of age. The total number of obligate anaerobes was higher than those of facultative anaerobes during the experimental period. At 6 weeks of age, the colonization of Bacteroides spp., Bifidobacterium spp. and Lactobacillus spp. was already detectable at high concentrations, whereas Clostridium spp. and Eubacterium spp. were not detected. The expression of proinflammatory cytokines (IL-1 β , IL-8 and TNF- α ) appeared at 8 weeks of age, and these were detectable until 17 weeks. A similar pattern was observed in the expression of Th1 cytokines (IL-2, IL-12 and IFN- &#110 ). On the other hand, the expression of Th2 cytokines (IL-4, IL-10 and TGF- β ) was weak. IL-4 mRNA expression was weakly detectable only at 6 and 8 weeks of age. The expression of IL-10 and TGF- β mRNA was scarcely detectable throughout the experimental period. Conclusion: The development of colitis may be mediated by both the predominant expression of Th1 cytokines and the weakness of Th2 cytokine expression in the mucosa. The colonization of anaerobic bacteria, especially Bacteroides spp., may be initiating and promoting these cytokine responses.     

Comparative in vitro activity of ceftaroline,ceftaroline-avibactam,and other antimicrobial agents against aerobic and anaerobic bacteria cultured from infected diabetic foot wounds

Foot infections are the most common infectious complication of diabetes. Moderate to severe diabetic foot infections (DFI) are typically polymicrobial with both aerobic and anaerobic organisms. The role of MRSA in these wounds has become an increasing concern. To determine if the addition of avibactam, a novel non-beta-lactam beta-lactamase inhibitor, to ceftaroline would be more active than ceftaroline alone, we tested 316 aerobic pathogens and 154 anaerobic recovered from patients with moderate to severe DFI, and compared ceftaroline with and without avibactam to other agents. Testing on aerobes was done by broth microdilution and by agar dilution for anaerobes, according to CLSI M11-A8, and M7-A8 standards. Ceftaroline-avibactam MIC₉₀ for all Staphylococcus spp. including MRSA was 0.5 μg/mL, and for enterococci was 1 μg/mL. The MIC₉₀s for enteric Gram-negative rods was 0.125 μg/mL. The addition of avibactam to ceftaroline reduced the ceftaroline MICs for 2 strains of resistant Enterobacter spp. and for 1 strain of Morganella. Against anaerobic Gram-positive cocci ceftaroline-avibactam had an MIC₉₀ 0.125 μg/mL and for clostridia 1 μg/mL. Avibactam improved ceftaroline’s MIC₉₀s for Bacteroides fragilis from >32 to 2 μg/mL and for Prevotella spp. from >32 to 1 μg/mL. Ceftaroline alone demonstrates excellent in vitro activity against most of the aerobes found in moderate to severe DFI. The addition of avibactam provides an increased spectrum of activity including the beta-lactamase producing Prevotella, Bacteroides fragilis and ceftaroline resistant gram-negative enteric organisms.