Drug sensitivity of Enterococcus sp. strains isolated from clinical material or from healthy persons

The aim of this study was to evaluate the drug susceptibility of Enterococcus sp. strains isolated in 2000-2001, from patients of five Warsaw's hospitals (154 strains) and from fecal samples of healthy persons (33 strains). On biochemical reaction profiles species of clinical enterococci were identified as: E. faecalis--66.2%, E. faecium--29.2%, E. hirae--1.9%, E. gallinarum--1.3%, E. casseliflavus--0.6% and E. avium--0.6%. The species of enterococci from stool's samples were identified as: E. faecalis--28 strains, E. durans--2 strains and single strains: E. faecium, E. gallinarum and E. casseliflavus. Susceptibility to 20 antibiotics was tested by disc diffusion method. None of these 187 enterococcal strains was vancomycin resistant; 3 strains of E. gallinarum and 1--E. casseliflavus demonstrated intermediately susceptibility to vancomycin, but they were susceptible to teicoplanin--phenotype Van C. Among clinical strains were resistant to penicillin--33.3% of E. faecalis and 100% of E. faecium, to ampicillin--over 80% of E. faecium and 1 strain of E. faecalis. None of these strains produced beta-lactamase. High-level resistance to aminoglicoside was expressed by 48 strains (47.1%) E. faecalis and 36 (80%) E. faecium isolated from clinical specimens. Both--HLR to streptomycin and gentamycin were found in 28.3% of E. faecalis and 68.9% of E. faecium. Among 33 strains isolated from fecal samples of healthy persons--3 of E. faecalis were resistant to streptomycin and one was resistant to both gentamicin and streptomycin. In general, enterococcal strains isolated from samples of healthy persons were susceptible to the most of used antibiotics. But to rifampicin none of these strains were susceptible. There were about 40% of E. faecalis strains isolated from healthy persons, resistant to tetracyline.     

Antimicrobial resistance of Enterococcus species isolated from produce

The purpose of this study was to characterize the antibiotic resistance profiles of Enterococcus species isolated from fresh produce harvested in the southwestern United States. Among the 185 Enterococcus isolates obtained, 97 (52%) were Enterococcus faecium, 38 (21%) were Enterococcus faecalis, and 50 (27%) were other Enterococcus species. Of human clinical importance, E. faecium strains had a much higher prevalence of resistance to ciprofloxacin, tetracycline, and nitrofurantoin than E. faecalis. E. faecalis strains had a low prevalence of resistance to antibiotics used to treat E. faecalis infections of both clinical and of agricultural relevance, excluding its intrinsic resistance patterns. Thirty-four percent of the isolates had multiple-drug-resistance patterns, excluding intrinsic resistance. Data on the prevalence and types of antibiotic resistance in Enterococcus species isolated from fresh produce may be used to describe baseline antibiotic susceptibility profiles associated with Enterococcus spp. isolated from the environment. The data collected may also help elucidate the role of foods in the transmission of antibiotic-resistant strains to human populations.     

临床分离肠球菌的耐药性研究

目的了解近3年来粤东地区临床分离的肠球菌的耐药特征,为预防耐万古霉素肠球菌（VRE）的产生和控制VRE播散提供理论依据和实验基础。方法收集临床分离的215株肠球菌,细菌鉴定及药敏试验采用VITEK-60全自动细菌鉴定仪。结果215株肠球菌中,尿标本中分离肠球菌75株（35％）;痰液中分离出34株（16％）。粪肠球菌141株（65．5％）,屎肠球菌74株（34．5％）。粪肠球菌对万古霉素、呋喃妥因、青霉素G和莫西沙星的敏感率较高,70％～100％;对红霉素和四环素的敏感性较差,11％～33％。屎肠球菌对万古霉素敏感性较好为100％,四环素为62％;而对呋喃妥因、高链霉素、青霉素和左氧氟沙星等敏感性较差（5％～47％）。未检出耐万古霉素肠球菌。结论粤东地区近3年来未发现耐万古霉素肠球菌。肠球菌对各种常见抗生素敏感程度呈下降趋势。屎肠球菌较粪肠球菌耐药性更高。应根据细菌学培养结果合理用药,减少耐药菌株的发生率。     

肠球菌的临床感染与耐药性分析

目的了解温州医学院附属第一医院临床分离主要肠球菌的分布及其对常用抗菌药物的耐药现状,以指导临床合理用药。方法对2008年至2011年临床分离的635株粪肠球菌和屎肠球菌的标本来源和药敏结果进行回顾性分析。结果各种临床标本中两种肠球菌的分布比例存在差异,总体以尿液标本所占比例最多,且屎肠球菌的总体分离率高于粪肠球菌。粪肠球菌对利奈唑胺、氨苄西林、万古霉素、呋喃妥因和替考拉宁的耐药率都在5．0％以下,对莫西沙星和青霉素G的耐药率也仅为7．0％和6．7％;屎肠球菌对莫西沙星、左旋氧氟沙星、环丙沙星、氨苄西林、青霉素G和红霉素的耐药率都在90．0％以上,对利奈唑胺、万古霉素、替考拉宁和奎奴敏感。粪肠球菌的多重耐药株占总数的26．4％,屎肠球菌的多重耐药株占总数的78．2％。结论粪肠球菌和屎肠球菌对15种抗菌药物的耐药情况不同,屎肠球菌具有更高的耐药率和更广的耐药谱。临床应根据药敏试验的结果合理选择抗菌药物,以防止耐药菌株的产生和播散。     

临床分离肠球菌的分布特征及耐药性分析

目的:了解我院临床分离肠球菌的分布特征及耐药现状,为临床合理用药提供依据。方法:对我院2010年1月至2012年12月期间所有临床分离的肠球菌分布情况及药敏结果进行回顾性分析。结果:临床共分离肠球菌242株,粪肠球菌分离率(55.0%)高于屎肠球菌(40.9%),屎肠球菌分离率有增高的趋势。标本来源以尿液(62.9%)、分泌物(10.3%)、血液(6.9%)为主。肠球菌对万古霉素、替考拉宁的敏感性最高,均高于90%。发现耐万古霉素的肠球菌(VRE)7株,其中5株同时耐高浓度的氨基糖苷类抗生素(HLAR);对克林霉素、复方磺胺、阿米卡星、庆大霉素、妥布霉素、苯唑西林耐、头孢西丁耐药率最高,均高于95%。屎肠球菌对青霉素类、氨苄西林、红霉素、呋喃妥因、环丙沙星耐药率均高于粪肠球菌;对四环素、奎努普丁/达福普汀耐药率低于粪肠球菌。结论:肠球菌是临床感染重要病原菌,且具有多重耐药性,屎肠球菌和粪肠球菌耐药水平差异较大,临床应根据药敏结果合理选择抗菌药物。     

High level of aminoglycoside resistance among Enterococcus faecalis and Enterococcus faecium strains

Enterococcus sp. strains are believed as important reason of serious nosocomial infections currently. These infections are cured by using combination of beta-lactams and aminoglycosides for their treatment. Enterococcus sp. resistant to high-level doses of aminoglycosides, beta-lactams and vancomycin are responsible for therapeutic failure. The aim of our study was to evaluate the incidence of isolation and susceptibility to antibiotics of HLAR Enterococcus sp. strains isolated between 2007 and 2010 from the patients of University Hospital No. 1 of dr A. Jurasz Collegium Medicum of L. Rydygier in Bydgoszcz Nicolaus Copernicus University in Toruń. Amongst 6137 Enterococcus sp. strains 1124 (18,3%) presented HLAR phenotype; 53,1% of them was identified as E. faecalis and 46,9% as E. faecium. The highest percentage of all examined strains was isolated from the patients of different surgery clinics, Intensive Care Units, and Pediatrics, Hematology and Oncology Clinic. HLAR and HLSR phenotypes were noted in E. faecalis, for 45,7% and 27,5% strains, in E. faecium - 29,8% and 9,5%, respectively. HLGR phenotype was presented twice more often in E. faecium than E. faecalis. Highest percentages of E. faecium resistant to glycopeptides and rifampicin were observed when compared with E. faecalis. The highest percentages of strains intermediate, resistant to vancomycin and resistant to glycopeptides were noted for E. faecium strains with phenotypes HLAR, HLGR and HLSR.     

泌尿外科住院患者泌尿系感染病原菌分布及其耐药性分析

了解泌尿外科住院患者泌尿系感染病原菌的分布及其对常用抗菌药物的耐药情况。对泌尿外科泌尿系感染住院患者的消毒中段尿培养结果进行回顾性分析,尿培养菌株的鉴定、药敏分析和统计分析采用VITEK2全自动微生物仪。3 a中泌尿外科泌尿系感染住院患者共分离到细菌1 233株,其中革兰阴性杆菌772株,占62.61%,革兰阳性球菌353株,占28.63%,真菌82株,占6.65%。菌株数居前5位的细菌依次为:大肠埃希菌、肠球菌属、洋葱伯克霍尔德菌、假丝酵母菌属和变形杆菌。分离大肠埃希菌产ESBLs率为66.18%,粪肠球菌中未发现VRE菌株,屎肠球菌VRE为0.8%。未发现对美洛培南耐药的大肠埃希菌,对肠埃希菌耐药率在10%以下的有亚胺培南、阿米卡星、哌拉西林/他唑巴坦和呋喃妥因。洋葱伯克霍尔德菌和铜绿假单胞菌对所监测的抗菌药物均有不同程度的耐药。未发现对万古霉素、替考拉宁及氨苄西林耐药的粪肠球菌。泌尿系感染的病原菌以大肠埃希菌和肠球菌为主,非发酵革兰阴性杆菌及假丝酵母菌所占比例超过20%,不容忽视,病原菌的耐药率较高,临床医生应根据尿培养和药敏试验结果合理使用抗菌药物。     

Incidence of virulence factors and antibiotic resistance among Enterococci isolated from food

The incidence of virulence factors among 48 Enterococcus faecium and 47 Enterococcus faecalis strains from foods and their antibiotic susceptibility were investigated. No strain was resistant to all antibiotics, and for some strains, multiple resistances were observed. Of E. faecium strains, 10.4% were positive for one or more virulence determinants, compared to 78.7% of E. faecalis strains. Strains exhibiting virulence traits were not necessarily positive for all traits; thus, the incidence of virulence factors may be considered to be strain specific.     

A note on antibiotic resistance in the bacterial flora of raw sewage and sewage-polluted River Tigris in Mosul, Iraq

Polluted water samples collected from the River Tigris in the vicinity of a raw sewage outfall were examined for the incidence of antibiotic resistance among coliform bacteria on three occasions during 1983. Eighty percent or more of the coliform bacteria were resistant to one or more antibiotics. At the same time, raw sewage samples were examined for the incidence of antibiotic-resistant bacteria, and Escherichia coli, Pseudomonas spp. and Staphylococcus spp. were selected for sensitivity testing. Collectively, more than 90% of the 480 strains of the three organisms were resistant to one or more antibiotics. The minimal inhibitory concentration (MIC) of ampicillin for twenty-nine strains including coliforms, E. coli, Klebsiella sp., Serratia sp., Ps. aeruginosa, Pseudomonas sp., Micrococcus sp., Staph. aureus, Streptococcus faecalis and Bacillus sp. from raw sewage and polluted River Tigris water was determined and that for Ps. aeruginosa was 250 micrograms/ml. The high incidence of antibiotic-resistant bacteria in natural waters could be related to the widespread use of antibiotics in this locality.     

Oxidative stress involved in the antibacterial action of different antibiotics

Staphylococcus aureus and Escherichia coli sensitive to chloramphenicol incubated with this antibiotic suffered oxidative stress with increase of anion superoxide (O2-). This reactive species of oxygen was detected by chemiluminescence with lucigenin. S. aureus, E. coli, and Enterococcus faecalis sensitive to ciprofloxacin exhibited oxidative stress when they were incubated with this antibiotic while resistant strains did not show stimuli of O2-. Other bacteria investigated was Pseudomonas aeruginosa, strains sensitive to ceftazidime and piperacillin presented oxidative stress in presence of these antibiotics while resistant strains were not stressed. Higher antibiotic concentration was necessary to augment O2- in P. aeruginosa biofilm than in suspension, moreover old biofilms were resistant to oxidative stress caused by antibiotics. A ceftazidime-sensitive mutant of P. aeruginosa, coming from a resistant strain, exhibited higher production of O2- than wild type in presence of this antibiotic. There was relation between antibiotic susceptibility and production of oxidative stress.     

Enumeration and antibiotic resistance patterns of fecal indicator organisms isolated from migratory Canada geese (Branta canadensis)

Thermotolerant fecal indicator organisms carried by migratory waterfowl may serve as reservoirs of antibiotic resistance. To determine the extent to which such antibiotic resistance markers were present in migratory Canada geese (Branta canadensis) on the Maryland Eastern Shore, we isolated Enterococcus spp. and Escherichia coli from fresh feces and examined the antibiotic resistance profiles of these bacteria. Samples were obtained in October 2002, January 2003, and March 2003. Thermotolerant E. coli counts ranged from 0 to 1.0x10(7) colony forming units (CFU)/0.1g (g-1) wet weight of feces, whereas Enterococcus spp. counts ranged from 1.0x10(2)-1.0x10(7) CFU g-1 wet weight of feces. Primary isolates of each indicator organism were tested against a panel of 10 antibiotics. Greater than 95% of E. coli isolates were resistant to penicillin G, ampicillin, cephalothin, and sulfathiazole; no E. coli were resistant to ciprofloxacin. Enterococcal isolates showed highest resistance to cephalothin, streptomycin, and sulfathiazole; no enterococci were resistant to chloramphenicol. The tetracyclines, streptomycin, and gentamycin provided the greatest discrimination among E. coli isolates; chlortetracycline, cephalothin, and gentamycin resistance patterns provided the greatest discrimination between enterococcal strains. Multiple antibiotic resistance (MAR) profiles were calculated: fall (E. coli=0.499; enterococci=0.234), winter (E. coli=0.487; enterococci=0.389), and spring (E. coli=0.489; enterococci=0.348). E. faecalis and E. faecium, which are recognized human nosocomial pathogens, were cultured from winter (44 and 56%, respectively) and spring (13 and 31%, respectively) fecal samples.     

Determination of antibiotic resistance and resistance plasmids of clinical Enterococcus species

To determine the antibiotic resistance pattern and resistance plasmids, we studied 23 antibiotic-resistant clinical isolates of Enterococcus spp. which caused infection in Bayindir-Ankara Hospital, Turkey. Biochemical and physiological identification tests were applied by the Vitek system and compared with the results of protein profiles by SDS-PAGE. From 23 isolates, 20 were identified as E. faecalis, 2 as E. faecium and 1 as E. gallinarum. Twenty four antibiotics belong to 10 different groups were used in susceptibility tests. Multiple antibiotic resistance was determined in 10 of 23 Enterococcus spp. Overall resistance to the used antibiotics was 47.3% and low level resistance was 16.6%. Among the isolates tested, 8.7% demonstrated high level gentamicin resistance, 17.4% demonstrated high level streptomycin resistance, and 43.5% demonstrated penicillin resistance. High level vancomycin resistant Enterococcus spp. rate was 34.8%, and 60.9% exhibited low level resistance to vancomycin and teicoplanin. They contain plasmids which varied in numbers between 1 and 11 and the plasmid sizes ranged from 2.08 to 56.15 kb. In curing experiments with acriflavine, two different plasmids were shown in different molecular sizes of 33.49 and 13.6 kb while the first determined glycopeptide and penicillin resistance, the second one determined either glycopeptide or penicillin resistance in two different E. faecalis strains. On the other hand, a 22.58 kb plasmid, determining kanamycin resistance, was detected in an E. faecium strain. After the curing experiments, an elimination of 37.17 and 44.47 kDa protein bands was shown in E. faecium EFA1 and E. faecalis EFA13 in SDS-PAGE, respectively. This survey indicates the increase of antibiotic-resistant enterococci, especially to vancomycin in our hospital isolates.     

Antibiotic resistance and virulence traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates

This study compared virulence and antibiotic resistance traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates. E. faecalis isolates harboured a broader spectrum of virulence determinants compared to E. faecium isolates. The virulence traits Cyl-A, Cyl-B, Cyl-M, gel-E, esp and acm were tested and environmental isolates predominantly harboured gel-E (80% of E. faecalis and 31.9% of E. faecium) whereas esp was more prevalent in clinical isolates (67.8% of E. faecalis and 70.4% of E. faecium). E. faecalis and E. faecium isolated from water had different antibiotic resistance patterns compared to those isolated from clinical samples. Linezolid resistance was not observed in any isolates tested and vancomycin resistance was observed only in clinical isolates. Resistance to other antibiotics (tetracycline, gentamicin, ciprofloxacin and ampicillin) was detected in both clinical and water isolates. Clinical isolates were more resistant to all the antibiotics tested compared to water isolates. Multi-drug resistance was more prevalent in clinical isolates (71.2% of E. faecalis and 70.3% of E. faecium) compared to water isolates (only 5.7% E. faecium). tet L and tet M genes were predominantly identified in tetracycline-resistant isolates. All water and clinical isolates resistant to ciprofloxacin and ampicillin contained mutations in the gyrA, parC and pbp5 genes. A significant correlation was found between the presence of virulence determinants and antibiotic resistance in all the isolates tested in this study (p<0.05). The presence of antibiotic resistant enterococci, together with associated virulence traits, in surface recreational water could be a public health risk.     

Partial characterization of enterocin MR99 from a corn silage isolate of Enterococcus faecalis

AIMS: To assess the inhibitory activity on Gram-positive and Gram-negative bacteria of several species of enterococci recovered from a natural corn silage. METHODS AND RESULTS: The inhibitory activity of strains of Enterococcus faecalis (58), Enterococcus faecium (35), Enterococcus gallinarum (3) and Enterococcus casseliflavus (4) were studied employing indicator strains from various sources (clinical, food and ATCC). Enterococcus faecalis MR99, the only strain with inhibitory activity, inhibited other enterococci, Listeria spp., Staphylococcus aureus, Clostridium spp., Bacillus spp., Escherichia coli, Shigella sonnei and Shigella flexneri. The bacterium contained only one conjugative pheromone-responsive plasmid. The partially chromatography-purified MR99 enterocin (PPE) had a molecular weight of approx. 5000 Da and a pI of 6.2, was sensitive to proteolytic enzymes and could be extracted in benzene and butanol. It appeared stable to adjustment of pH 4.0, 5.0, 6.0, 7.0 and 8.0 and was resistant to heat. Inactivation was at 15 min at 121 degrees C. Enterocin MR99 was bactericidal on strains of Listeria monocytogenes, Staph. aureus, and bovine mastitis agents, it was bacteriostatic on E. coli. Although enterocins MR99 and AS48 have inhibitory activity on Gram-negative bacilli, PCR studies demonstrated a lack of relationship between them. CONCLUSIONS: The active component had a protein nature, was resistant to heat and presented a wide inhibitory spectrum. SIGNIFICANCE AND IMPACT OF THE STUDY: The biological properties of Ent. faecalis MR99 suggest that this strain merits further investigations so it can be applied in human and veterinary health programmes.     

Comparative study of vanA gene transfer from Enterococcus faecium to Enterococcus faecalis and to Enterococcus faecium in the intestine of mice

Vancomycin-resistant enterococci represent a large reservoir in animals because of the use of avoparcin as a growth promoter in Europe. These strains of animal origin enter the food chain and can either colonize the human gut or transfer their resistance genes to the human microbiota. In this study, we compared the transfer of vancomycin resistance from resistant animal Enterococcus faecium to sensitive human Enterococcus faecalis and E. faecium. We analysed these transfers in dibiotic mice and human faecal flora-associated mice. VanA transfer from animal E. faecium to human E. faecalis occurred in dibiotic mice. The transconjugants appeared rapidly and persisted at levels between 3.0 and 4.0 log10 colony-forming units g(-1) of faeces. In human faecal flora-associated mice, vanA gene transfer was not detected towards E. faecalis but was possible between E. faecium strains. Our experiments revealed the possibility of vanA transfer from animal E. faecium to human E. faecalis in vitro and in vivo in the intestine of dibiotic mice. However, intraspecies transfer of vanA gene seems more common than interspecies transfer among enterococci.     

Investigation of distribution,species composition,and degree of resistance to antibiotics of the bacteria of the <Emphasis Type="Italic">Enterococcus</Emphasis> genus in Lake Baikal

The paper presents the result of investigation of species composition, distribution and degree of resistance to antibiotics of the Enterococcus bacteria in Lake Baikal. It is shown that they live in littoral zones of the lake. In the deep-water part of the lake the studied microorganisms are not found. We isolated 120 strains identified as E. faecium, E. avium, E. faecalis, E. mundii, E. hirae, E. durans, E. gallinarum. On the whole, the strains of enterococcus isolated from Lake Baikal are characterized as antibiotic-sensitive. Nevertheless, the antibiotic-resistant strains of enterococci are found in the studied collection, including those with typical intermediate level of resistance to vancomycin.     

A note on antibiotic resistance in the bacterial flora of raw sewage and sewage-polluted River Tigris in Mosul, Iraq

Polluted water samples collected from the River Tigris in the vicinity of a raw sewage outfall were examined for the incidence of antibiotic resistance among coli-form bacteria on three occasions during 1983. Eighty percent or more of the coli-form bacteria were resistant to one or more antibiotics. At the same time, raw sewage samples were examined for the incidence of antibiotic-resistant bacteria, and Escherchia coli, Pseudomonas spp. and Staphylococcus spp. were selected for sensitivity testing. Collectively, more than 90% of the 480 strains of the three organisms were resistant to one or more antibiotics. The minimal inhibitory concentration (MIC) of ampicillin for twenty-nine strains including coliforms, E. coli, Klebsiella sp., Serratia sp., Ps. aeruginosa, Pseudomonas sp., Micrococcus sp., Staph. aureus, Streptococcus faecalis and Bacillus sp. from raw sewage and polluted River Tigris water was determined and that for Ps. aeruginosa was 250 μg/ml. The high incidence of antibiotic-resistant bacteria in natural waters could be related to the widespread use of antibiotics in this locality.     

Characterisation and transfer of antibiotic resistance genes from enterococci isolated from food

The genetic determinants responsible for the resistances against the antibiotics tetracycline [tet(M), tet(O), tet(S), tet(K) and tet(L)], erythromycin (ermA,B,C; mefA,E; msrA/B; and ereA,B) and chloramphenicol (cat) of 38 antibiotic-resistant Enterococcus faecium and Enterococcus faecalis strains from food were characterised. In addition, the transferability of resistance genes was also assessed using filter mating assays. The tet(L) determinant was the most commonly detected among tetracycline-resistant enterococci (94% of the strains), followed by the tet(M) gene, which occurred in 63.0% of the strains. Tet(K) occurred in 56.0% of the resistant strains, while genes for tet(O) and tet(S) could not be detected. The integrase gene of the Tn916-1545 family of transposons was present in 81.3% of the tetracycline resistant strains, indicating that resistance genes might be transferable by transposons. All chloramphenicol-resistant strains carried a cat gene. 81.8% of the erythromycin-resistant strains carried the ermB gene. Two (9.5%) of the 21 erythromycin-resistant strains, which did not contain ermA,B,C, ereA,B and mphA genes harboured the msrC gene encoding an erythromycin efflux pump, which was confirmed by sequencing the PCR amplicon. In addition, all E. faecium strains contained the msrC gene, but none of the E. faecalis strains. Transfer of the genetic determinants for antibiotic resistance could only be demonstrated in one filter mating experiment, where both the tet(M) and tet(L) genes were transferred from E. faecalis FAIR-E 315 to the E. faecalis OG1X recipient strain. Our results show the presence of various types of resistance genes as well as transposon integrase genes associated with transferable resistances in enterococci, indicating a potential for gene transfer in the food environment.     

湖北地区部分医院肠球菌耐药性监测及相关因素分析

目的：了解湖北地区2000年度肠球菌的分离情况及耐药状况,并对抗感染用药进行探索,指导临床合理用药。方法：对湖北地区15所三甲医院各类临床标本中的538株肠球菌采用API细菌鉴定系统或Vitek全自动细菌鉴定系统进行分离鉴定,用纸片扩散法进行药敏试验,并以WHO细菌耐药监测网提供的WHONET4软件分析系统对试验数据进行分析处理。结果：本试验共分离肠球菌13个种别538株,其中大多数是粪肠球菌408株,占75.8%,屎肠球菌54株,占10.0%;坚忍肠球菌24株,占4.46%;鸟肠球菌10株,占1.86%。酪黄肠球菌6株,占1.11%;母鸡肠球菌6株,占1.11%等。本研究结果表明肠球菌的主要感染部位为泌尿道31.4%和各种分泌物31.0%。同时从药敏结果可见屎肠球菌和坚忍肠球菌对大多数抗生素的耐药性高于粪肠球基本国策 ;并发现糖肽类抗生素耐药菌株比例尚不高;庆大霉素呈高水平耐药球菌株比例则较高;对青霉素和氨卞西林耐药,本研究结果亦有反映,并且鸟肠球菌的耐药性高于粪肠球菌近三倍。结论：本年度分离的肠球菌占全年总分离菌的第六位,说明我国目前由肠球菌引起的感染所占比例不高,但仍应引起临床的高度重视,并进行动态的监测。加强对肠球菌特别是VRR耐药性的监测是非常必要的,泌尿道肠球菌感染的抗生素中呋喃妥因的耐药率较四环素和喹诺酮类药物为低,故仍不失为治疗该类泌感的首选药物,菌株差别与地区有关,由于肠球菌属中的不同种对抗生素的敏感性不同。因此种的鉴定是对该地区医院感染暴发流行,选择治疗方案的重要工具。     

Susceptibility to antimicrobial agents and genotypic relatedness of enterococcal strains isolated from patients and hospital environment

The aim of this study was to evaluate antibiotic susceptibility of Enterococcus sp. strains isolated from two hospitals in ?ód?, during 2005-2006. The second goal was to determine possible transmission of these strains within hospital wards by using melting profile PCR. Enterococcal strains were identified to species according standard microbiological methods. There was isolated 159 strains of E. faecalis, 51 strains of E. faecium and two E. avium, 1 E. durans. Susceptibility to antimicrobial agents was tested by disc diffusion method. None of these strains was resistant to vancomycin, teicoplanin or linezolid. There was high percentage of strains resistant to aminoglicosides, 22% of E. faecalis strains, and 54.9% of E. faecium strains, respectively. Additionally it was shown that 11.7% of E. faecium is resistant to chinuprisin-dalfopristin. The strains with similar pattern of resistance to antibiotics and fenotypic characteristics were genotyped by mpPCR. This technique was useful to confirm relatedness of bacterial strains suspected of being spread within hospital wards.