危重监护病房铜绿假单胞菌耐药性及脉冲场凝胶电泳分析

目的　了解我院危重监护病房 (简称 ICU)铜绿假单胞菌的耐药性。建立一种快速、准确、可靠、重复性好的基因分型方法来研究 ICU铜绿假单胞菌的分子流行病学。方法　采用全自动鉴定仪 ( Walkaway-4 0 DADE Microscan Inc)鉴定铜绿假单胞菌 ,并根据半定量微量肉汤系统测定 7种常用抗生素对细菌的最低抑菌浓度 ,确定其耐药情况。用脉冲场凝胶电泳 (简称 PFGE)对限制性酶切片段分离。通过对每一株菌染色体DNA指纹图谱的比较分析其克隆构成 ,了解其流行状况。结果　 2 4株菌对 7种抗生素的耐药性由高到低依次为 :环丙沙星 ( 87.5 % ) ,庆大霉素 ( 75 % ) ,亚胺培南 ( 6 6 .7% ) ,头孢曲松 ( 6 6 .7% ) ,哌拉西林 ( 2 9.2 % ) ,头孢他啶 ( 2 0 .8% ) ,阿米卡星 ( 12 .5 % )。8株菌经 PFGE分析初步证实其中 4株菌具有明显相关性。结论　铜绿假单胞菌对常用抗菌药物的耐药率高 ,多重耐药情况严重。 PFGE具有分辨力高、重复性好的特点 ,是研究 ICU铜绿假单胞菌分子流行病学较好的基因分型方法     

Antibiotic resistance in Pseudomonas aeruginosa: mechanisms and impact on treatment

Pseudomonas aeruginosa continues to be a major cause of infections in Western society, in part because of its high intrinsic resistance to antibiotics. It has been demonstrated that this intrinsic resistance arises from the combination of unusually restricted outer-membrane permeability and secondary resistance mechanisms such as energy-dependent multidrug efflux and chromosomally encoded periplasmic β-lactamase. Given this high level of natural resistance, mutational resistance to most classes of antibiotics can readily arise. In this review we summarize new insights into the mechanisms of resistance, and describe therapeutic approaches that can be used in the face of this continuing resistance threat, as well as new approaches that are being developed to combat resistance.     

Antibiotic resistance

Antibiotic resistance is an increasing problem in many parts of the world. Antibiotic resistance has been associated with the use of some antibiotics but not with others. Due to the overuse of antibiotics with a high resistance potential, there has been an increase of resistance with certain bacteria, e.g., Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pneumoniae. This article discusses the antibiotics associated with a high resistance potential and those that are safe to use with a low resistance potential. Strategies for minimizing antibiotic resistance are discussed.     

医院大肠埃希菌和铜绿假单胞菌的分布及耐药性分析

目的分析我院2012~2015年住院患者大肠埃希菌和铜绿假单胞菌的临床分布及耐药性,为临床合理用药提供依据。方法对2012~2015年的临床标本按常规进行病原菌分离,采用VITEK2全自动细菌鉴定与药敏分析仪对大肠埃希菌和铜绿假单胞菌进行鉴定。结果共分离出大肠埃希菌3 210株,其中产超广谱β-内酰胺酶(ESBLs)菌株1 916株,占59.69%,主要来源于尿液(45.95%),感染科室主要分布于普外科(30.21%)和重症医学科(26.54%)。铜绿假单胞菌2 585株,其中多药耐药菌株311株,占12.03%,主要来源于痰液84.09%,感染科室主要分布于呼吸内科(44.56%)和重症医学科(23.07%);大肠埃希菌对美罗培南、亚胺培南、头孢替坦、哌拉西林/他唑巴坦和厄他培南的耐药率较低(≤5%),对氨苄西林、哌拉西林和头孢唑啉的耐药率较高(≥50%);铜绿假单胞菌对阿米卡星和头孢吡肟耐药率较低(≤10%)。结论我院住院患者大肠埃希菌和铜绿假单胞菌感染分布较广,对常见抗菌药物呈现不同程度的耐药性。医院加强对病原菌的耐药性监测,对指导临床合理使用抗菌药物及减缓多药耐药菌株的形成具有重要意义。     

Antibiotic resistance: the challenge from an industry perspective

Trained in medical microbiology and infectious diseases in the UK, Glenn Tillotson has over 20 years pharmaceutical experience in various areas, including clinical research, marketing, scientific communications, strategic development and global launch programs. Mainly in the field of anti-infectives, Tillotson has been instrumental in the development of ciprofloxacin and moxifloxacin, as well as other drugs in the Bayer portfolio. After leaving Bayer, he worked as a consultant microbiologist and, in 2003, consulted with Genesoft to help with the commercialization and launch of gemifloxacin, leading to the development of Oscient following the merger of Genesoft and Genome Therapeutics. From late 2003 to early 2006, he focused his efforts on the launch of gemifloxacin into US clinical practice, as well as comarketing and business development deals globally. In April 2006, Tillotson joined Replidyne Inc. as Executive Director of Scientific Affairs working on faropenem, REP 8839 and REP 3123. Presently, Tillotson is Head of Medical Affairs at ViroPharma Inc., where he oversees educational, publication and other related activities for Vancocin^®, maribavir and Cinryze?. Most recently, Tillotson was a member of the Scientific Steering Committee for the International Society of Chemotherapy’s Symposium on Clostridium difficile in Leipzig, Germany. Here, he talks with Expert Review of Clinical Pharmacology about the challenge of antibiotic resistance from an industry perspective.     

Antibiotic resistance in staphylococci

When penicillin was introduced in 1944 over 94% of Staphylococcus aureus isolates were susceptible; by 1950 half were resistant. By 1960 many hospitals had outbreaks of virulent multi-resistant S. aureus. These were overcome with penicillinase-stable penicillins, but victory was brief; methicillin-resistant S. aureus (MRSA) were recorded in the year of the drug's launch. MRSA owe their behaviour to an additional, penicillin-resistant peptidoglycan transpeptidase, PBP-2', encoded by mecA. Their spread is clonal, with transfer of mecA being extremely rare. MRSA accumulated and then declined in the 1960s and 1970s, but became re-established in the early 1980s. Some early MRSA strains were colonists rather than invaders and the proportion of MRSA among S. aureus bacteraemias in England remained under 3% until 1992. However, this proportion rose to 34-37% by 1998-1999, reflecting the dissemination of two new epidemic strains, EMRSA 15 and 16. These may be more virulent than earlier MRSA, or their success may reflect changing hospital practice. Until 1996, glycopeptides were universally active against S. aureus; then glycopeptide-intermediate S. aureus (GISA) were found in Japan, France, and the USA. This resistance is associated with increased wall synthesis. Coagulase-negative staphylococci (CNS) are less pathogenic than S. aureus but are important in line-associated bacteraemias and prosthetic device infections. They are even more often resistant than S. aureus, notably to teicoplanin. Few anti-staphylococcal agents were launched from 1970 to 1995, but the situation is now improving. Dalfopristin/quinupristin inhibits virtually all S. aureus, although its bactericidal activity is impaired against strains with constitutive MLSB-type resistance; other new agents are in advanced development. New agents give a renewed opportunity for control, but S. aureus is a resilient foe, able to regain its importance if drugs are used profligately or if hygiene is slackened.     

Antibiotic resistance from two perspectives: man and microbe

Despite much effort, antibiotic resistance continues to increase. Looking back, it is clear that this was an inevitable consequence of antibiotic use. From a bacterial viewpoint, the introduction of antibiotics was a tremendous stimulus to evolution. As a survival reaction to stress (selection pressure) bacteria, by means of their extreme biochemical and genetic versatility, have adapted to 21st Century conditions. Resistance can be to some extent contained by less and better use of antibiotics, but ultimately novel approaches to the treatment and prevention of infectious diseases will have to be forthcoming. This will only be achieved if best use is made of alternative resources presently available and most importantly, man's ingenuity must be fully engaged.     

Antibiotic resistance among enterococcal strains isolated from clinical specimens

The distribution and resistance patterns of clinical isolates of enterococci from hospital patients were compared with those obtained from outpatients. Of 235 enterococcal isolates 212 (90.2%) were identified as Enterococcus faecalis and 23 (9.8%) as E. faecium. E. faecium occurred more frequently in specimens from hospitalized patients than from outpatients (P < 0.001). Over 90% of all E. faecalis isolates were susceptible to ampicillin. Resistance to ampicillin occurred in 66.7% of hospital strains of E. faecium. High-level resistance to gentamicin (MIC > 500 mg/l) was seen in 37.03% of inpatients' and in 11.5% of outpatients' E. faecalis isolates and in 76.2% of hospital isolates of E. faecium. High-level streptomycin resistance (MIC > 2000 mg/l) occurred in 52.8% of E. faecalis and 76.2% of E. faecium hospital isolates. There were no isolates resistant to vancomycin. The community acquired strains isolated from outpatients were more susceptible than isolates from hospitalized patients to all antimicrobial agents tested.     

Antibiotic resistance of bacterial biofilms

A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and DNA. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and disinfectant chemicals as well as resisting phagocytosis and other components of the body's defence system. The persistence of, for example, staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infection in cystic fibrosis patients is caused by biofilm-growing mucoid strains. Characteristically, gradients of nutrients and oxygen exist from the top to the bottom of biofilms and these gradients are associated with decreased bacterial metabolic activity and increased doubling times of the bacterial cells; it is these more or less dormant cells that are responsible for some of the tolerance to antibiotics. Biofilm growth is associated with an increased level of mutations as well as with quorum-sensing-regulated mechanisms. Conventional resistance mechanisms such as chromosomal β-lactamase, upregulated efflux pumps and mutations in antibiotic target molecules in bacteria also contribute to the survival of biofilms. Biofilms can be prevented by early aggressive antibiotic prophylaxis or therapy and they can be treated by chronic suppressive therapy. A promising strategy may be the use of enzymes that can dissolve the biofilm matrix (e.g. DNase and alginate lyase) as well as quorum-sensing inhibitors that increase biofilm susceptibility to antibiotics.     

Antibiotic resistance patterns in Pseudomonas aeruginosa: an 8-year surveillance study in a French hospital

The susceptibility to ticarcillin, piperacillin, ceftazidime, aztreonam, tobramycin, amikacin, ciprofloxacin and fosfomycin of 3876 strains of Pseudomonas aeruginosa isolated during the period 1989-1996 in a French hospital was investigated. The most frequently active agents were amikacin and ceftazidime to which 13.3% and 16.1% of the isolates were resistant. Analysis of beta-lactam susceptibility patterns suggested that cephalosporinase derepression and intrinsic resistance were the predominant underlying mechanisms. There was a trend towards a decline in susceptibility to beta-lactams, aminoglycosides and ciprofloxacin over time. Multiresistance was frequent, mainly in O11 and O12 isolates.     

老年患者医院下呼吸道感染铜绿假单胞菌耐药性分析

目的探讨老年患者医院下呼吸道感染铜绿假单胞菌（PAE）耐药特点,为临床合理选用抗菌药物和预防泛耐药菌的发生提供依据。方法回顾性分析和评价2010年5月至2012年6月347例老年患者医院下呼吸道感染PAE药物敏感试验结果。结果347例老年患者医院下呼吸道感染PAE对抗菌药物的耐药较严重,氨苄西林、头孢唑啉耐药率均为100．O％,氨苄西林／舒巴坦、妥布霉素、磺胺甲嗯唑／甲氧苄啶耐药率分别为95．1％、86．8％、83．6％。对亚胺培南耐药率已达19．6％,泛耐药菌的检出率为4．9％。结论老年患者医院下呼吸道感染PAE耐药性日趋严重,应根据药物敏感试验结果合理选择抗菌药物,防止泛耐药菌的产生与流行。     

Laboratories "Produits Scientia" and mineral waters from Pougues and Carabana

In the end of XIXth century, the french "Compagnie des eaux minérales de Pougues-les-Eaux" begins to exploit the spanish natural purgativ water of Caraba?a. In the same way, Edouard Jéramec, director of the french compagny, decides to associate to his firm the best medicine to fight against rickets and tuberculosis. He joins the new medical theory wich recommends to give more calcium to tubercular patients, called "méthode de recalcification du Dr Ferrier". Then, with the chemist Emile Perraudin, he creates the pharmaceutical laboratory named "Produits Scientia". One of their famous patents medicines will be the "Tricalcine".     

铜绿假单胞菌耐药机制的研究进展

铜绿假单胞菌是耐药性较强的病原菌,β-内酰胺酶的生成和外排泵的表达是产生固有耐药和获得性耐药的重要机制。除了已经熟知的机制外,最新的研究运用多种技术手段如微阵列技术和基因突变频率分析等对铜绿假单胞菌的耐药机制进行了更进一步的研究;同时铜绿假单胞菌的适应性耐药的研究也取得了很大进展。综述近年来发表的有关铜绿假单胞菌耐药机制的研究文献,并对其耐药机制的研究进展作了分析。     

Antibiotic sensitivity and plasmid profiles of Pseudomonas aeruginosa

OBJECTIVE: To determine the susceptibility of Pseudomonas aeruginosa to commonly used antibiotics and to study the relationship between antibiotic resistance and the plasmid profiles of the organism. DESIGN: Cross sectional study SETTING: Samples of burns, wound pus, urine, blood, sputum, stool and aspirates were obtained from Harare Hospital (n = 120) and Parirenyatwa Hospital(n = 80). SUBJECTS: Male and female patients either admitted or attending clinics. MAIN OUTCOME MEASURES: P. aeruginosa isolates obtained were resistant to commonly used antibiotics in this environment. The resistance may be plasmid-dependent. RESULTS: P. aeruginosa is prevalent in burns (76.7%) and wounds (67.5%) and in their respective hospital wards. The isolates of P. aeruginosa were resistant to gentamicin (65.5%); carbenicillin (61.9); polymyxinb (53.0%); ciprofloxacin (61.1%) and ceftriazone (70.8%); but showed high sensitivity to tazocin (89.4%) and nalidixic acid (59.3%) and cotrimoxazole (54.9%). All the isolates resistant to the antibiotics tested possessed plasmid DNA. Strains with four plasmids of molecular weight of approximately, 1.5 x 10(6), 1.8 x 10(6), 2.9 x 10(6) and 7.4 x 10(6) Da showed multiple resistance to the drugs that were tested. CONCLUSION: This study reveals an emergence of multiple antibiotic-resistant strains of P. aeruginosa. The traditional drugs gentamicin, carbenicillin, ciproflaxacin, and polymyxin-b used for treatment of P. aeruginosa infections may no longer be reliable. Therefore, a newer drug such as tazocin and other rarely used drugs such as nalidixic acid should be considered for P. aeruginosa antibiotic therapy.     

393例儿童感染铜绿假单胞菌耐药性分析

目的了解湖南省儿童医院临床分离的铜绿假单胞菌感染分布及耐药情况。方法回顾性分析该院2010年1月至2010年12月住院患儿的各类临床标本中分离出的铜绿假单胞菌分布情况及其对16种抗菌药物的耐药情况。结果共分离出铜绿假单胞菌393株,主要来源于痰及咽拭子、血液;集中在心血管内科、急诊综合科、新生儿科、感染科、重症监护科等;对氨苄西林、头孢唑啉、氨苄西林-舒巴坦、呋喃妥因等不敏感,敏感率均<10%,对头孢吡肟、哌拉西林-他唑巴坦、氨曲南、环丙沙星、左氧氟沙星、美罗培南等耐药率较低,耐药率均<10%。结论铜绿假单胞菌是医院感染的主要病原菌之一,耐药形势严峻;应高度重视重点病区感染流行的监测及消毒工作,结合药敏试验结果,合理使用抗菌药物。