SEARCH · PubMed Health

Results for “Enterococcus faecalis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,279 records · Page 71Linked to original sources

PubMed1998

Low faecal carrier rate of vancomycin resistant enterococci in Norwegian hospital patients.

The faecal carrier rate of vancomycin resistant enterococci (VRE) was surveyed among 616 patients in selected departments of 7 Norwegian hospitals. One Enterococcus gallinarum isolate harbouring a vanB2 element was recovered from a child with malignant disease treated with vancomycin and ceftazidime. No vancomycin resistant Enterococcus faecalis or Enterococcus faecium were detected and no VRE isolates of the VanA type were identified. The low level of VRE carriage corresponds to the limited use of glycopeptide antibiotics for human therapeutic purposes in Norway. It indicates a low risk of acquiring VRE infections in Norwegian hospitals.

Anti-Bacterial Agents↗

PubMed1997

Effect of vancomycin on intestinal flora of patients who previously received antimicrobial therapy.

To evaluate the ecological disturbances of peroral vancomycin administration following cephalosporin administration, 20 healthy volunteers received cefuroxime axetil tablets (250 mg) perorally twice a day for 1 week, and 10 of these volunteers subsequently received vancomycin capsules (125 mg) perorally four times daily for 7 days. The concentration of vancomycin in feces after 1 week of vancomycin administration was high (mean +/- SD, 520 +/- 197 mg/kg), which correlated with the ecological disturbances noted in the vancomycin recipients. Vancomycin administration resulted in a rapid decrease in the numbers of intestinal Enterococcus faecium, Enterococcus faecalis, and Enterococcus durans (P < or = .05), while there was a significant emergence of motile enterococci with decreased susceptibility to vancomycin (Enterococcus gallinarum and Enterococcus casseliflavus; minimum inhibitory concentration, 4-16 mg/L) (P < or = .01). Because of vancomycin administration, there was also a significant overgrowth of vancomycin-resistant Pediococcus species and lactobacilli as well as of Klebsiella species, Citrobacter species, and Enterobacter species (P < or = .01). The numbers of bifidobacteria and Bacteroides species were significantly reduced during vancomycin administration. None of the enterococcal strains carried vanA or vanB. Twenty-two of the 27 motile enterococci carried the vanC-1 gene specific for E. gallinarum, whereas five strains carried the vanC-2(C-3) gene, thus implicating that they were E. casseliflavus or Enterococcus flavescens.

Administration, Oral↗

PubMed2003

Antimicrobial resistance in recent fecal enterococci from healthy volunteers and food handlers in Spain: genes and phenotypes.

Susceptibility patterns to 15 different antibiotics and the presence of resistance genes were evaluated in recent fecal Enterococcus isolates recovered from 42 healthy volunteers (HV) and 43 food-handlers (FH). A total of 142 Enterococcus faecalis, 74 Enterococcus faecium, and 23 Enterococcus spp. with different antibiotic susceptibility patterns were studied. A higher percentage of resistance for moxifloxacin, erythromycin, glycopeptides and high-level resistance (HLR) to gentamicin were observed in the FH group. Ampicillin- or linezolid-resistant isolates were not recovered in any of the groups. The tet(M) gene was found in 96% and in 85% of tetracycline-resistant isolates from HV and FH, respectively. HLR-kanamycin was mediated by aph(3')-IIIa, or aac(6')-aph(2"), or both genes in all isolates from HV group and in 86% from FH group. The aac(6')-aph(2") gene was found in all HLR-gentamicin isolates. Ninety-one percent of HV and 71% of FH erythromycin-resistant isolates harbored the erm(B) gene (erythromycin MIC range of 8-128 microg/ml), whereas erm(A), erm(C), or mef(A) genes were not detected. Coexistence of erm(B), aph(3')-IIIa, and tet(M) genes was observed in 17% of the isolates of both groups. The HLR-gentamicin isolates presented unrelated PFGE patterns while 2 out of 3 vanA E. faecium isolates showed an indistinguishable SmaI-pulsed-field gel electrophoresis (PFGE) pattern. This study shows that despite 4 years of official banning of antibiotic growth promoters in animals, enterococci isolated from FH are more resistant than those from HV. This suggests the permanence of resistant clones or transferable resistance elements in farms and a possible exchange between food products and humans, or eventually the long-term permanence of certain clones in the FH intestinal tract.

Anti-Bacterial Agents↗

PubMed2004

Characterization of high-level aminoglycoside-resistant enterococci in Kuwait hospitals.

This study investigated the distribution of genes for aminoglycoside-modifying enzymes (AME) and the genetic relatedness of high-level aminoglycoside-resistant enterococci isolated in Kuwait hospitals. A total of 117 enterococci, consisting of 109 Enterococcus faecalis, seven Enterococcus faecium, and one Enterococcus casseliflavus were studied. The MICs of gentamicin, kanamycin, amikacin, tobramycin, and streptomycin were determined by agar dilution and the genes encoding the AAC(6')- APH(2"), ANT(4'), APH(3'), APH (2")-Ib, APH (2")-Ic, APH (2")-Id, and ANT(6) enzymes were amplified by PCR. They were typed by pulsed-field gel electrophoresis (PFGE). Filter mating was used to transfer gentamicin resistance determinants. They were all resistant to kanamycin (MIC 2000 mg/L). Fifty-five isolates were resistant to gentamicin (MIC 500 mg/L), 72 were resistant to tobramycin (MIC 64 mg/L), 115 were resistant to amikacin (MIC 64 mg/L), and 97 were resistant to streptomycin (MIC 1000 mg/L). The aac(6')-Ie-aph(2")-Ia was detected in all isolates with gentamicin MIC 500 mg/L and in 15 isolates with gentamicin MIC 256 mg/L. The aph(3')-IIIa gene was detected in 101 isolates, whereas the ant(6')-Ia gene was detected in 85 of the 97 streptomycin-resistant isolates with MIC 1000 mg/L. The aac(6')-Ii gene was detected only in the seven E. faecium isolates. None of them contained ant(4')-Ia, aph(2")-Ib, aph(2")-Ic and aph(2")-Id. PFGE revealed heterogeneous patterns with no dominant clone. The results demonstrated that AME are common in aminoglycoside-resistant enterococci isolated in Kuwait. However, the absence of a dominant clone suggests that they acquired high-level aminoglycoside independently.

Aminoglycosides↗

PubMed1997

In-vitro study of the synergy between beta-lactam antibiotics and glycopeptides against enterococci.

The synergy between glycopeptides and beta-lactams was studied using different techniques such as broth macrodilution, killing curves and agar dilution combined with agar diffusion. Two glycopeptide-resistant enterococci isolated from different clinical samples were used. Results showed different effects with significant changes in MICs. Antibacterial activity was related to the concentration of glycopeptide and beta-lactam for Enterococcus faecalis 8253, while for Enterococcus faecium 8072 a paradoxical effect was observed. With this strain, the best synergic effect was detected at teicoplanin concentrations of 1-4 mg/L, but antibacterial activity was reduced at concentrations of 8, 16 and 32 mg/L. No synergic effect was observed with vancomycin. The combination of agar dilution with agar diffusion techniques may constitute a simple method for routine detection of synergic effects between glycopeptides and beta-lactams.

Anti-Bacterial Agents↗

PubMed1997

The in-vitro activity of trovafloxacin, a new fluoroquinolone, against Gram-positive bacteria.

The in-vitro activity of trovafloxacin, a new quinolone, was compared with that of ciprofloxacin, erythromycin, various beta-lactam antibiotics and, where appropriate, clindamycin and vancomycin against a range of Gram-positive bacteria including staphylococci (n = 201), Streptococcus pneumoniae (n = 83), beta-haemolytic streptococci (n = 46), viridans group streptococci (n = 100), Streptococcus milleri (n = 18) and enterococci (n = 161) by an agar dilution technique. In addition, time-kill studies were performed to estimate the bactericidal activity of trovafloxacin against S. milleri and viridans group streptococci. Trovafloxacin was the most active agent tested against staphylococci. It also showed good activity, at least four-fold and usually eight- to 16-fold that of ciprofloxacin, against all the streptococci. Trovafloxacin showed good activity against vancomycin-sensitive Enterococcus faecalis and Enterococcus faecium, but was less active against the 11 isolates of vancomycin-resistant enterococci. Trovafloxacin showed comparable or superior bactericidal activity to amoxycillin against the S. milleri and viridans group streptococci tested.

Anti-Bacterial Agents↗

PubMed1998

The effects of increasing levels of quinolone resistance on in-vitro activity of four quinolones.

A panel of 266 clinically isolated Gram-positive cocci and Gram-negative bacilli with varying levels of resistance to ciprofloxacin were analysed for susceptibility to Du-6859a, ciprofloxacin, ofloxacin, temafloxacin and nalidixic acid. Staphylococci were divided into ciprofloxacin-susceptible, moderately resistant and highly resistant subgroups. Du-6859a was the most potent quinolone against all taxa. As ciprofloxacin resistance increased to high levels, MICs of all quinolones increased but Du-6859a MICs increased least, and ciprofloxacin MICs increased most. Less susceptible single-step mutants were selected from 80% of 15 representative clinical isolates exposed to ciprofloxacin, 71% of isolates exposed to temafloxacin, 67% of isolates exposed to Du-6859a and 53% of isolates exposed to ofloxacin. Du-6859a inhibited more mutants (67%) at a concentration of 1 mg/L than did the other quinolones (26-43%) at their susceptible breakpoints. Du-6859a was the most rapidly bactericidal quinolone in time-kill studies with Enterococcus faecalis and Enterococcus faecium. This study indicated that Du-6859a is more potent than the comparator quinolones, is less affected by the mechanisms responsible for high-level quinolone resistance and may be less likely to select resistant mutants if it has a susceptible breakpoint of 1 mg/L.

Anti-Infective Agents↗

PubMed2000

Enterococcal glycopeptide resistance at an Italian teaching hospital.

Two thousand one hundred and thirteen strains of enterococci isolated at Pisa General Hospital in 1998 were analysed retrospectively to determine their glycopeptide resistance. Of all the microorganisms isolated in this period, 14.7% were enterococci (1405 Enterococcus faecalis, 19 Enterococcus faecium, six Enterococcus avium and 683 Enterococcus spp.). Two hundred and thirty (10.8%) of these enterococci were resistant or demonstrated reduced susceptibility to vancomycin and/or teicoplanin. The highest rate of resistance was found in outpatient enterococcal strains isolated from the urogenital tract. The frequency of enterococcal glycopeptide resistance at Pisa Hospital is higher than that reported from other areas of Italy.

Anti-Bacterial Agents↗

PubMed2001

Activity of daptomycin against Gram-positive pathogens: a comparison with other agents and the determination of a tentative breakpoint.

The in vitro activity of daptomycin was studied in comparison with other agents active against 328 recent clinical isolates of Gram-positive pathogens. MIC data showed that the addition of calcium ions to a final concentration of 50 mg/L enhanced the activity of daptomycin generally by eight- to 16-fold. In the presence of calcium ions daptomycin was uniformly active against the strains of Staphylococcus spp. and Streptococcus spp. studied with a MIC90 of < or = 1 mg/L. Enterococcus faecalis and Enterococcus faecium were slightly less susceptible (MIC90 2 mg/L). Vancomycin-, fluoroquinolone- and quinupristin/dalfopristin-resistant strains were all susceptible to daptomycin. The presence of serum reduced the apparent activity of daptomycin to only a moderate extent. Employing the BSAC methodologies, a tentative breakpoint of 2 mg/L for daptomycin is proposed.

Anti-Bacterial Agents↗

PubMed2002

In vitro activity of a new cephalosporin, RWJ-54428, against streptococci, enterococci and staphylococci, including glycopeptide-intermediate Staphylococcus aureus.

The need for new antimicrobial agents with activity against Gram-positive organisms has become increasingly important because of emerging resistance. We compared the activity of a new b-lactam antimicrobial agent, RWJ-54428 (MC-02 479), with representatives of other classes of antimicrobial agents against 76 Staphylococcus aureus (including four glycopeptide- intermediate strains), 50 coagulase-negative staphylococci, 20 Enterococcus faecalis, 20 Enterococcus faecium, 10 Enterococcus gallinarum/Enterococcus casseliflavus, 54 Streptococcus pneumoniae and 22 viridans streptococcal isolates. The MIC(90) of RWJ-54,428 was < or = 2 mg/L for all groups of bacteria tested except E. faecium. The activity against four strains of glycopeptide-intermediate S. aureus was similar to that for other methicillin-resistant S. aureus isolates (range 0.5-2.0 mg/L).

Acetamides↗

PubMed2004

Calcium-supplemented daptomycin Etest strips for susceptibility testing on Iso-Sensitest agar.

OBJECTIVE: Iso-Sensitest agar (ISA), which is recommended by the BSAC for routine susceptibility testing of staphylococci and enterococci, contains insufficient calcium for testing daptomycin. Isotonic agar supplemented with 50 mg/L calcium has been advocated, but is not routinely available in many laboratories. We evaluated a daptomycin Etest that incorporates a constant level of calcium throughout the daptomycin gradient, designed to give an appropriate concentration around the strip during testing, as an alternative for susceptibility testing on ISA. METHODS: Ninety-one isolates of Staphylococcus aureus (45 methicillin-susceptible, 46 methicillin-resistant) and 90 enterococci (47 Enterococcus faecalis, 43 Enterococcus faecium) were tested. Daptomycin Etest MICs were determined on ISA, whereas agar dilution MICs were determined in parallel on Isotonic agar supplemented with calcium to 50 mg/L as a control. RESULTS: The agar dilution and Etest MIC ranges of daptomycin for S. aureus were 0.25-1 mg/L (mode 0.5 mg/L), and 0.125-2 mg/L (mode 0.25 mg/L), respectively. The corresponding MIC values for enterococci were 0.25-4 mg/L (mode, 1 mg/L) and 0.125-4 mg/L (mode, 2 mg/L). For staphylococci, 86% of the Etest MIC results were within one dilution of the agar dilution values, and for enterococci, 90% of the Etest MIC results met these criteria. When results from the two methods were not identical, there was a tendency for the Etest MIC values to be lower than the agar dilution values. CONCLUSIONS: This study shows that calcium-supplemented daptomycin Etests on ISA are an accurate and convenient alternative to calcium-supplemented Isotonic agar.

Anti-Bacterial Agents↗

PubMed2006

FT-IR microspectroscopy for early identification of some clinically relevant pathogens.

AIMS: To investigate the potentials and limitations of Fourier transform-infrared (FT-IR) microspectroscopy as a tool to identify, at the level of microcolonies, pathogenic bacteria frequently isolated in the clinical environment. METHODS AND RESULTS: A total of 1570 FT-IR spectra from 164 gram-positive and gram-negative bacteria isolated from patients were recorded from 6 to 10-h old microcolonies of 50-150 microm size. A classification of 100% was obtained for the most frequent gram-positive bacteria, such as Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Enterococcus faecium at the species level. An average accuracy of about 80% was reached with Gram negative bacteria from the Enterobacteriaceae and Pseudomonaceae families; Enterobacter aerogenes, Enterobacter cloacae, Klebsiella spp., and Citrobacter koseri; and Proteus mirabilis and Escherichia coli. Results were comparable with FT-IR measurements on dried suspensions from 18-h cultures. CONCLUSIONS: Early identification of young microcolonies is feasible with FT-IR microscopy with a very high accuracy for gram-positive bacteria. Some improvement in the transfer of microcolonies is necessary to increase the accuracy for gram-negative bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Combination of FT-IR microscopy and multivariate data analysis could be a complementary, rapid, and reliable tool for screening and discriminating, at species and subspecies level, micro-organisms of clinical, food-borne, or environmental origins.

Animals↗

PubMed1997

Efficacy and safety of vancomycin constant-rate infusion in the treatment of chronic Gram-positive bone and joint infections.

OBJECTIVE: To evaluate the efficacy and safety of vancomycin constant-rate infusion over 24 h in the treatment of Gram-positive bone infections, METHODS: Vancomycin (40 mg/kg/day) was administered without a loading dose to 15 patients (12 male, three female) aged 23--90 years, weighing 46--85 kg, with postoperative chronic bone and joint infections. The 24-h dose was adjusted to maintain plasma levels between 25 and 35 mg/L. Mean duration of therapy was 6.2 months (4--8.5) via a portable infusion pump. Sites of infection included hip and femur (10), tibia (three), patella (one) and vertebrae (one). Sequestrectomy (two), removal of material (7/8 prosthetic hips, 1/5 metal implants) and debridement (two) were performed at the beginning of the treatment. Involved bacteria included Staphylococcus aureus (eight, six methicillin resistant), S. epidermidis (four methicillin-resistant), Enterococcus faecalis (one), Enterococcus avium (one) and Streptococcus bovis (one). RESULTS: MIC of vancomycin ranged from 1 to 4 mg/L. The mean vancomycin bone concentration when available was 67.7plus minus38.9 microg/L. Based on a mean post-treatment follow-up of 14plus minus4 months (6--20.6), cure was achieved in 10 patients (66.6%). Failures were related to the inability to remove the infected prosthesis (one) or implants (three) and to the persistence of a deep wound abcess (one). Adverse events included pruritus (four cases), tinnitus (two), mild transient elevation of creatinine level (three) and transient neutropenia (two). Vancomycin was maintained in all the patients. CONCLUSIONS: Prolonged treatment with vancomycin constant-rate infusion is effective and safe for treatment of Gram-positive chronic bone and joint infections, providing that complete surgical débridement and prosthetic material removal are performed.

Journal Article↗

PubMed1997

Comparison of agar-based media for primary isolation of glycopeptide-resistant enterococci.

OBJECTIVE: To compare four vancomycin-containing agar media for the isolation of glycopeptide-resistant enterococci (GRE) from clinical fecal specimens: kanamycin---aesculin---azide (KAA) agar; bile---aesculin---polymixin (BAP) agar; aztreonam---amphotericin blood (CBAA) agar; and neomycin blood (CBN) agar. METHODS: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin. RESULTS: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium. CONCLUSIONS: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity.

Journal Article↗

PubMed2006

Antimicrobial resistance among faecal enterococci from healthy individuals in Portugal.

Analysis of 247 faecal enterococcal isolates from 99 healthy Portuguese individuals during 2001 revealed the presence of enterococci resistant to vancomycin (5%) and highly resistant to streptomycin (52%), kanamycin (40%) or gentamicin (11%). Most isolates were also resistant to tetracycline, erythromycin, ciprofloxacin and quinupristin-dalfopristin. The vanA (two Tn1546 types), vanC1, erm(B), aac(6')-aph(2'')-Ia, aph(3')-IIIa, vat(E) and vat(D) genes were detected. Enterococcus faecalis and Enterococcus faecium isolates with high-level resistance to gentamicin were related to Portuguese poultry isolates described previously. E. faecium isolates that were highly resistant to vancomycin or gentamicin harboured different housekeeping purK alleles associated previously with different hosts.

Animals↗

PubMed1990

Biological characterization of a new radioactive labeling reagent for bacterial penicillin-binding proteins.

Radiolabeled penicillin G is widely used as the imaging agent in penicillin-binding protein (PBP) assays. The disadvantages of most forms of labeled penicillin G are instability on storage and the long exposure times usually required for autoradiography or fluorography of electrophoretic gels. We investigated the utility of radioiodinated penicillin V as an alternative reagent. Radioiodination of p-(trimethylstannyl)penicillin V with [125I]Na, using a modification of the chloramine-T method, is simple, high yielding, and site specific. We demonstrated the general equivalence of commercially obtained [3H]penicillin G and locally synthesized [125I]penicillin V (IPV) in their recognition of bacterial PBPs. Profiles of PBPs in membranes from Bacteroides fragilis, Escherichia coli, Providencia rettgeri, Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis, and Enterococcus faecium labeled with IPV or [3H]penicillin G were virtually identical. Use of IPV as the imaging agent in competition experiments for determination of the affinities of various beta-lactam antibiotics for the PBPs of E. coli yielded results similar to those obtained in experiments with [3H]penicillin G. Dried electrophoretic gels from typical PBP experiments, using IPV at 37.3 Ci/mmol and 30 micrograms/ml, exposed X-ray film in 8 to 24 h. The stability of IPV on storage at 4 degrees C was inversely proportional to specific activity. At 37.3 Ci/mmol and 60 micrograms/ml, IPV retained useful activity for at least 60 days at 4 degrees C. IPV represents a practical and stable reagent for rapid PBP assays.

Autoradiography↗

PubMed1994

Comparative in vitro activity of DU-6859a, a new fluoroquinolone agent, against gram-positive cocci.

The in vitro activity of DU-6859a (DU), a new fluoroquinolone agent, was evaluated against 233 gram-positive cocci and was compared with those of ciprofloxacin, vancomycin, nafcillin, and ampicillin. The MICs of DU for 90% of the staphylococci tested were < or = 0.06 microgram/ml. All of the groups A and B and viridans group streptococci were inhibited by < or = 0.125 microgram of DU per ml, which was 32-fold more active than ciprofloxacin. On the basis of MICs for 90% of the strains tested, DU was 32- and 16-fold more active than ciprofloxacin against Enterococcus faecalis and Enterococcus faecium, respectively. The bactericidal activity of DU was demonstrated by time-kill techniques against all ciprofloxacin-susceptible enterococci. DU shows promise for the treatment of infections with gram-positive cocci and warrants further evaluation by in vitro and in vivo studies.

Anti-Bacterial Agents↗

PubMed1994

In vitro activities of two glycylcyclines.

The in vitro activities of two glycylcyclines, CL 329,998 and CL 331,002 (two new semisynthetic tetracyclines), were evaluated in comparison with those of tetracycline and other available oral antimicrobial agents. A total of 523 recent clinical isolates were studied, including strains resistant to tetracycline. Members of the family Enterobacteriaceae were generally > or = 16-fold more susceptible to the glycylcyclines than to tetracycline (although less difference was seen with Proteus spp.). Pseudomonas aeruginosa was modestly susceptible to both new compounds (MIC for 90% of strains tested [MIC90], 16 micrograms/ml). Tetracycline- and methicillin-susceptible and -resistant strains of Staphylococcus aureus were all susceptible to the glycylcyclines (MIC90 < or = 1 microgram/ml). Streptococci (including Streptococcus pneumoniae) and Enterococcus faecalis and Enterococcus faecium displayed a bimodal distribution of susceptibility to tetracycline yet were uniformly susceptible to the glycylcyclines (MIC90 < or = 0.25 microgram/ml). The glycylcyclines were highly potent against Neisseria, Moraxella, Haemophilus, and Bacteroides spp. (MIC90 < or = 0.5 microgram/ml). Strains of Chlamydia spp. (three C. trachomatis strains and one C. pneumoniae strain) were inhibited by < or = 0.25 microgram of CL 329,998 or CL 331,002 per ml. Two strains of Mycoplasma pneumoniae were inhibited by < or = 0.12 microgram of CL 331,002 per ml and by 1 microgram of CL 329,998 per ml. Mycobacterium tuberculosis and Mycobacterium avium were resistant to the two glycylcyclines (MIC > or = 8 micrograms/ml). These results indicate that the two glycylcyclines have potent in vitro activities against a wide range of clinically important pathogenic bacteria.

Bacteria↗