SEARCH · Search PubMed

Results for “enterococci”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

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

At least 145 records · Page 8Linked to original sources

PubMed1990

In-vitro activity of vancomycin, teicoplanin, daptomycin, ramoplanin, MDL 62873 and other agents against staphylococci, enterococci and Clostridium difficile.

The minimum inhibitory concentrations (MICs) of different antibiotics were determined by a broth microdilution method for staphylococci, enterococci and Clostridium difficile. The antimicrobial agents tested were vancomycin, teicoplanin, daptomycin, ramoplanin, MDL 62873, rifampicin and piperacillin, the latter limited to enterococci. In terms of MIC90S, daptomycin (0.89 mg/l). MDL 62873 (0.99 mg/l), and teicoplanin (1.50 mg/l) were found to be highly active against methicillin-resistant Staphylococcus aureus (MRSA). Daptomycin (MIC90 0.48 mg/l), MDL 62873 (0.95 mg/l) and ramoplanin (1.45 mg/l) were the most active drugs against methicillin-resistant S. epidermidis (MRSE). Teicoplanin (MIC90 0.45 mg/l) was the most active agent against enterococci, followed by MDL 62873 (0.65 mg/l) and daptomycin (1.60 mg/l). MDL 62873 gave the lowest MIC90 (0.17 mg/l) for C. difficile. Teicoplanin (MIC90 0.42 mg/l), daptomycin (0.87 mg/l) and ramoplanin (0.98 mg/l) were also very active. Our results indicate that teicoplanin, daptomycin, ramoplanin and MDL 62873, a teicoplanin derivative, are potentially effective alternative antibiotics for treatment of infections caused by staphylococci, enterococci and C. difficile.

Anti-Bacterial Agents↗

PubMed1997

Activity of a new glycopeptide antibiotic (LY333328) against enterococci and other resistant gram-positive organisms.

A new semi-synthetic glycopeptide, LY333328, was tested for in-vitro activity against 197 strains of enterococci including strains resistant to other glycopeptides. Activity was also assessed against species with intrinsic resistance to glycopeptides. For strains of enterococci tested the LY333328 MIC90s were < or = 0.5 mg/L. Enterococcus faecalis was less susceptible to LY333328 than other enterococci with a maximum MIC of 2.0 mg/L. Glycopeptide-resistant strains of enterococci were not more resistant to LY333328 than glycopeptide-susceptible strains but intrinsically resistant species had MICs between 4 and 8 mg/L.

Ampicillin↗

PubMed2001

In vitro and in vivo efficacy of a novel fluoro-ketolide HMR 3562 against enterococci.

The in vitro activity of HMR 3562, a new 2-fluoro-ketolide drug, was investigated against 95 enterococci, including 36 vancomycin-resistant strains. HMR 3562 inhibited 90% of enterococci susceptible or resistant to erythromycin A at 0.005 and 0.6 mg/L, respectively. HMR 3562 was highly active in murine peritonitis induced by five enterococci, irrespective of resistance phenotype, displaying effective doses in the range 3.4-21.8 mg/kg. The results demonstrate the potential of HMR 3562 in the treatment of infections caused by multiresistant enterococci.

Animals↗

PubMed1989

The enterococci: evidence of species-specific clinical and microbiologic heterogeneity.

Investigations of the clinical role of enterococci have been limited largely to enterococcal bacteremia and endocarditis and have not distinguished between the various species of enterococci. To characterize the full spectrum of enterococcal disease and to determine whether clinically important differences exist among infections and/or instances of colonization (infections/colonizations) by the various enterococcal species, cases of enterococcal infection/colonization diagnosed at the Dallas Veterans Administration Medical Center (DVAMC) in 1986 were reviewed. During this period, 220 Enterococcus faecalis, 21 Enterococcus faecium, 12 Enterococcus avium, and no Enterococcus durans isolates were identified in clinical specimens (other than stool) submitted to the DVAMC microbiology laboratory. Clinical characteristics of cases of infection/colonization by the three species of enterococci were similar and did not vary significantly when blood stream invasion occurred. Nevertheless, mortality data and therapeutic response rates suggested differences in virulence of the three enterococcal species. Enterococcal infections/colonizations (including bacteremia) frequently were polymicrobial. Although Enterobacteriaceae were the most common copathogens identified overall, Staphylococcus aureus was the most common copathogen in bloodstream infections. E. avium was more resistant than E. faecalis or E. faecium to penicillin G and ampicillin and less resistant to most other antimicrobial agents. The results of this investigation suggest that enterococci are a heterogeneous group of bacteria that should not be treated as a single entity in clinical investigations.

Anti-Bacterial Agents↗

PubMed2002

Osteomyelitis attributable to vancomycin-resistant enterococci.

Vancomycin-resistant enterococcus first was described in 1988, and has become a major problem in nosocomial infections. This is a retrospective review of 10 patients, seen at the authors' hospital during a 2-year period, with confirmed vancomycin-resistant enterococcal osteomyelitis: four patients had total joint arthroplasty infections, one patient had an infected tibial nail, three patients had infections associated with external fixators, and two patients had osteomyelitis of the femur. Four of the 10 patients had underlying medical illnesses (diabetes mellitus, systemic lupus erythematosus, human immunodeficiency virus infection); four of the 10 patients were intravenous drug users. Two patients had vancomycin-resistant enterococci on admission, and the other eight patients were admitted to the hospital for a mean of 21.3 days (range, 3-73 days) before vancomycin-resistant enterococci were identified in the bone. Eight of the 10 patients had monomicrobial infections with vancomycin-resistant enterococci. Patients were treated by surgical debridement, removal of hardware, and antibiotics (chloramphenicol in eight patients, quinupristin and dalfopristin (Synercid) in two patients). All patients initially improved with therapy, but one patient had a recurrence of vancomycin-resistant enterococcal osteomyelitis and died of bacteremia. Bone infections with vancomycin-resistant enterococcus still may be uncommon, but with time and selective antibiotic pressures, vancomycin-resistant enterococci may become a more prominent entity in orthopaedic infections.

Adult↗

PubMed2005

Enumeration and speciation of enterococci found in marine and intertidal sediments and coastal water in southern California.

AIMS: To determine the levels and species distribution of enterococci in intertidal and marine sediments and coastal waters at two beaches frequently in violation of bacterial water standards. METHODS AND RESULTS: Faecal indicator bacteria were extracted from sediment and enumerated using membrane filtration. High levels of enterococci were detected in intertidal sediments in a seasonal river and near a storm drain outlet. Low levels were found in marine sediments at 10 m depths and in surf zone sand. Bacterial isolates presumptively identified as Enterococcus on mEI media were speciated. The predominant species found in both water and sediment included Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. A number of isolates (11-26%) from regulatory water samples presumptively identified as enterococci on mEI media were subsequently identified as species other than Enterococcus. At both study sites, the distribution of species present in water was comparable with those in sediments and the distribution of species was similar in water samples passing and exceeding bacterial indicator standards. CONCLUSIONS: High levels of Enterococcus in intertidal sediments indicate retention and possible regrowth in this environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Resuspension of enterococci that are persistent in sediments may cause beach water quality failures and calls into question the specificity of this indicator for determining recent faecal contamination.

California↗

PubMed2006

Evaluation of novel fluorogenic substrates for the detection of glycosidases in Escherichia coli and enterococci.

AIMS: Enzyme substrates based on 4-methylumbelliferone are widely used for the detection of Escherichia coli and enterococci in water, by detection of beta-glucuronidase and beta-glucosidase activity respectively. This study aimed to synthesize and evaluate novel umbelliferone-based substrates with improved sensitivity for these two enzymes. METHODS AND RESULTS: A novel beta-glucuronide derivative based on 6-chloro-4-methylumbelliferone (CMUG) was synthesized and compared with 4-methylumbelliferyl-beta-D-glucuronide (MUG) using 42 strains of E. coli in a modified membrane lauryl sulfate broth. Over 7 h of incubation, the fluorescence generated from the hydrolysis of CMUG by E. coli was over twice that from MUG, and all of the 38 glucuronidase-positive strains generated a higher fluorescence with CMUG compared with MUG. Neither substrate caused inhibition of bacterial growth in any of the tested strains. Four beta-glucosidase substrates were also synthesized and evaluated in comparison with 4-methylumbelliferyl-beta-D-glucoside (MU-GLU) using 42 strains of enterococci in glucose azide broth. The four substrates comprised beta-glucoside derivatives of umbelliferone-3-carboxylic acid and its methyl, ethyl and benzyl esters. Glucosides of the methyl, ethyl and benzyl esters of umbelliferone-3-carboxylic acid, were found to be superior to MU-GLU for the detection of enterococci, especially after 18 h of incubation, while umbelliferone-3-carboxylic acid-beta-D-glucoside was inferior. However, the variability in detectable beta-glucosidase activity among the different strains of enterococci in short-term assays using the three carboxylate esters (7 h incubation) may compromise their use for rapid detection and enumeration of these faecal indicator bacteria. CONCLUSIONS: The beta-glucuronidase substrate CMUG appears to be a more promising detection system than the various beta-glucosidase substrates tested. SIGNIFICANCE AND IMPACT OF THE STUDY: The novel substrate CMUG showed enhanced sensitivity for the detection of beta-glucuronidase-producing bacteria such as E. coli, with a clear potential for application in rapid assays for the detection of this indicator organism in natural water and other environmental samples.

Cellulases↗

PubMed2006

Antibiotic resistance of enterococci and related bacteria in an urban wastewater treatment plant.

The main objective of this work was to study the ecology of enterococci and related bacteria in raw and treated wastewater from a treatment plant receiving domestic and pretreated industrial effluents in order to assess the influence of treatment on the prevalence of antibiotic resistance phenotypes among this group of bacteria. The predominant species found in the raw wastewater were Entercoccus hirae, Entercoccus faecium and Entercoccus faecalis. Wastewater treatment led to a reduction in E. hirae (alpha<0.1) and an increase in E. faecium (alpha<0.1); the relative proportions of E. faecalis remained the same in the raw and in the treated wastewater. Among the isolates tested, no vancomycin resistance was observed among the enterococci. Entercoccus faecium and E. faecalis showed resistance prevalence values reaching 33%, 40% and 57% for the antibiotics ciprofloxacin, erythromycin and tetracycline, respectively. Antibiotic-resistant strains of enterococci were not eliminated by wastewater treatment. A positive selection of ciprofloxacin-resistant enterococci was indicated by a significant increase in resistance prevalence (alpha<0.02) in treated wastewater compared with the raw wastewater.

Anti-Bacterial Agents↗

PubMed1999

Detection of clinical vancomycin-resistant enterococci in Denmark by multiplex PCR and sandwich hybridization.

Since the first cases of human infection with vancomycin-resistant enterococci (VRE) were reported in the late eighties, there has been a dramatic increase in VRE all over the world. So far, there have not been any reports of clinical VRE in Denmark. In this study we have investigated 131 clinically important enterococci sent to Statens Serum Institut from all over Denmark during the period July 1995 to May 1997. The susceptibility to vancomycin, teicoplanin, ampicillin and gentamicin was tested by the agar dilution method. In addition, two methods were developed to detect the different genotypes of glycopeptide resistance described in enterococci: a multiplex PCR assay for detection of vanA, vanB, vanC-1, vanC-2/3 ligase genes including 16S rRNA gene control primers and a sandwich hybridization assay to confirm vanA and vanB PCR-positive strains. The highest frequency of resistance to the tested antibiotics was found in the Enterococcus faecium group. Four strains were found with acquired resistance to glycopeptides: one E. faecium and one E. gallinarum were vanA positive, and two E. faecium isolates were vanB positive. These strains were isolated from different hospitals in different periods of time, and all patients recovered from their infections with VRE. Today, the PCR and sandwich hybridization methods are used for screening of vancomycin-resistant enterococci in humans as part of the Danish surveillance programme.

Ampicillin↗

PubMed2001

[Epidemiological study on vancomycin-resistant enterococci from fecal samples in the east area of Japan].

Recently, Vancomycin-resistant enterococci (VRE) have become important nosocomial pathogens in the world. In Japan, the VRE-infection was first reported in 1996. However, an epidemiological study on VRE has not been aggressively done in Japan. We conducted a survey study to explore the incidence and antimicrobial susceptibility of vancomycin-resistant enterococci isolated from fecal samples at 45 hospitals in the east area of Japan (Kanto, Koshinetsu, Tohoku, and Hokkaido) during June 1998 to March 1999. The Enterococcosel agar containing vanocomycin (BBL) was used for screening VRE from fecal samples in each hospital. The susceptibilities of the isolates to 8 antimicrobials were determined by the broth microdilution method and the definitions of resistance were based on current standards of the NCCLS standards. The VRE genotypes (vanA, vanB, vanC1, and van C2/3) were confirmed by amplifying the respective genes by PCR. Eight hundred and ninety four strains of enterococci were tested by the microtiter plates hybridization method (WAKUNAGA SEIYAKU, Japan). One thousand five hundred eighty three strains of enterococci were collected from 6,914 patients in 45 hospitals. These strains included 72 (4.5%) strains Enterococcus faecalis, 33 (2.1%) strains Enterococcus faecium, 17 (1.1%) strains Enterococcus avium, 1,040 (65.7%) strains Enterococcus gallinarum, 386 (24.4%) strains Enterococcus cassliflavus, and 35 (2.2%) strains Enterococcus flavescens. These strains of vancomycin-resistant E. faecalis were isolated from 3 patients, two of these 3 strains had van A gene and other one had van B gene. Those 3 strains were in the Kanto area, and 2 of 3 strains were in Tokyo, Generally, though van A type VRE was highly resistaant to both vancomycin and teicoplanin. In our study, two strains of van A type E. faecalis were highly resistant to vancomycin (MICs > 128 micrograms/ml) and susceptible to teicoplanin with MICs 4 micrograms/ml. Those two strains were different in susceptibilities of minocycline and ofloxacin. The result of the analysis of PFGE had also different patterns. VanB type E. fecalis was highly resistant to vancomycin and susceptible to teicoplanin (MICs 0.25 microgram/ml). For ampicillin and imipenem, 3 strains of E. faecalis were susceptible (MIC < or = 1 microgram/ml). One of 562 strains of E. gallinarum had vanB and vanC1 genes and was moderately resistant to vancomycin and susceptible to teicoplanin. All strains of E. casseliflavus and E. flavescens had vanC2/C3 gene only. All strains of E. faecium and E. avium did not detect van genes. From this result, it was supposed that VRE were very rare in the east of Japan.

Enterococcus↗

PubMed1977

Comparative in vitro activity of nafcillin, oxacillin, and methicillin in combination with gentamicin and tobramycin against enterococci.

The in vitro activity of nafcillin, oxacillin, and methicillin alone and in combination with gentamicin and tobramycin against 30 strains of enterococci was investigated. The penicillinase-resistant penicillins were less active than penicillin and ampicillin against the enterococci. Nafcillin was more active than oxacillin and methicillin. Sixty-six percent of strains were inhibited by nafcillin at 6.25 mug/ml, but none was inhibited by oxacillin and methicillin at the same concentration. At 12.5 mug/ml, 83, 16, and 0% were inhibited by nafcillin, oxacillin, and methicillin, respectively. By using a variety of criteria and analyses, it was shown that none of the antibiotic combinations studied demonstrated enhanced killing of all strains of enterococci. Nafcillin-gentamicin was the best combination, and enhanced killing was demonstrated against most strains. Oxacillin was more effective than methicillin when combined with gentamicin. Tobramycin was probably less effective than gentamicin in combination with the penicillinase-resistant penicillins against enterococci.

Anti-Bacterial Agents↗

PubMed1978

In vitro studies with Sch 21420 and Sch 22591: activity in comparison with six other aminoglycosides and synergy with penicillin against enterococci.

In vitro tests were performed with Sch 21420 and Sch 22591 to determine (i) their activity in comparison to six other aminoglycosides against 343 clinical isolates, and (ii) whether synergy with penicillin G could be demonstrated with enterococci. In broth dilution tests, Sch 22591 was more active than the seven other aminoglycosides against Staphylococcus aureus, Enterobacteriaceae, and most nonfermenting gram-negative bacilli. Sch 22591 was as active as tobramycin against Pseudomonas aeruginosa. The activity of Sch 21420 was comparable to gentamicin, sisomicin, netilmicin, and tobramycin but greater than amikacin or kanamycin against S. aureus and most genera of Enterobacteriaceae. Sch 21420, amikacin, and kanamycin were (i) more active than the other five aminoglycosides against Proteus rettgeri and Providencia stuartii, but (ii) less active than the other five aminoglycosides against Neisseria gonorrhoeae, enterococci, most nonfermenting gram-negative bacilli, Proteus mirabilis, and Proteus morganii. Studies on the bactericidal activity of Sch 22591 with penicillin indicated a synergistic interaction against enterococci, including strains highly resistant to streptomycin and kanamycin. This could be demonstrated with combinations containing 3.0 to 6.0 mug of Sch 22591 per ml and was comparable to that observed with penicillin/gentamicin. Penicillin plus Sch 21420 (25 mug/ml) also demonstrated synergy against enterococci, including strains highly resistant to streptomycin. However, synergy did not occur against strains highly resistant to kanamycin. These latter results were similar to those obtained in tests with penicillin/kanamycin.

Aminoglycosides↗

PubMed1982

Lack of in vivo and in vitro bactericidal activity of N-formimidoyl thienamycin against enterococci.

The minimal bactericidal concentrations of N-formimidoyl thienamycin (N-f-thienamycin) against 21 strains of enterococci isolated from patients with infective endocarditis were determined by macro- and microdilution methods. By a macrodilution technique with the minimal bactericidal concentration defined as greater than or equal to 99.9% killing of an initial inoculum, all 21 strains of enterococci were found to have minimal bactericidal concentration/minimal inhibitory concentration ratios of greater than or equal to 32. The mean minimal inhibitory concentration was 1.5 micrograms/ml (range, 0.5 to 4 micrograms/ml), and the minimal bactericidal concentration was greater than or equal to 128 micrograms/ml. The disparity between the results of our study and those published elsewhere, which reported that N-f-thienamycin is bactericidal in vitro against enterococci, may represent the relative insensitivity of the microdilution method in determining greater than or equal to 99.9% killing. The lack of in vitro bactericidal activity of N-f-thienamycin against enterococci was confirmed in vivo in the rabbit model of experimental endocarditis. N-f-Thienamycin was no more effective than penicillin alone in the treatment of experimental enterococcal endocarditis and was less effective than the combination of penicillin and gentamicin. The results indicate that N-f-thienamycin should not be used alone in the treatment of enterococcal endocarditis.

Animals↗

PubMed1987

In vitro and in vivo activity of ciprofloxacin against enterococci isolated from patients with infective endocarditis.

In vitro activity of ciprofloxacin against 27 strains of enterococci was inoculum dependent. Using inocula of 10(5) to 10(6) or 10(7) to 10(8) CFU of enterococci per ml, the MICs for 50 and 90% of strains tested increased from 1 to greater than or equal to 128 micrograms of ciprofloxacin per ml with the higher inoculum compared with the lower inoculum. The MBC for 50% of strains tested increased from 2 to greater than 128 micrograms/ml and the MBC for 90% of strains tested increased from 8 to greater than 128 micrograms of ciprofloxacin per ml with the lower and higher inocula, respectively. The combination of penicillin-gentamicin was more effective in vitro than the combination of ciprofloxacin-gentamicin against the low or high inoculum of enterococci. Using two strains of enterococci, we studied the efficacy of ciprofloxacin in the treatment of enterococcal experimental endocarditis in rabbits. Ciprofloxacin used alone or combined with gentamicin was significantly less effective (P less than 0.01) than procaine penicillin alone or procaine penicillin combined with gentamicin for the treatment of enterococcal experimental endocarditis. The combination of ciprofloxacin-procaine penicillin was not a more effective therapy than procaine penicillin alone.

Animals↗

PubMed1991

Lack of homology of enterococci which have high-level resistance to trimethoprim with the dfrA gene of Staphylococcus aureus.

Multiresistant enterococci were tested for susceptibility to trimethoprim (TMP). Although most enterococci are inhibited by less than or equal to 1.0 microgram/ml, the MICs for 7 of 29 selected multiresistant isolates were greater than or equal to 8 micrograms/ml, including for two beta-lactamase positive (Bla+) strains, for which the MICs of TMP were greater than 1,000 micrograms/ml, and for another Bla+ strain, for which the MIC was 128 micrograms/ml. None of five isolates tested transferred TMP resistance and none of the resistant isolates hybridized to the dfrA gene of Staphylococcus aureus. Whether TMP resistance in enterococci is due to a mutation(s) or to acquisition of a new gene is not known. Acquisition of resistance to TMP is another example of the multiple antimicrobial resistance typically displayed by enterococci.

Enterococcus faecalis↗

PubMed1992

Natural occurrence of structures in oral streptococci and enterococci with DNA homology to Tn916.

Seventeen oral streptococci and 18 enterococci were tested for the presence of DNA sequences homologous to the conjugative transposon Tn916 encoding tetracycline resistance. All the strains were resistant to tetracyclines, including minocycline, and most of them were resistant to other antibiotics. Tn916-like structures, identified by hybridization of HincII-digested DNA, were found on the chromosomes of 11 oral streptococci and four enterococci and on two plasmids, pIP1549 and pIP1440, one harbored by an Enterococcus hirae strain and the other harbored by an Enterococcus faecalis strain. Sequences homologous to Tn916, only some of which corresponded to its internal HincII structure (Tn916-modified elements), were chromosomally located in three oral streptococci and two enterococci and were plasmid borne in pIP614 harbored by an E. faecalis strain. Nine enterococci and three oral streptococci carried either the Tet M or the Tet O determinant chromosomally, but they carried no other sequences homologous to Tn916.

Anti-Bacterial Agents↗

PubMed1975

Synergism of oxacillin and gentamicin against enterococci.

Strains of enterococci isolated from 34 patients were studied for susceptibility to oxacillin and gentamicin alone and in combination. The minimal bactericidal concentrations of oxacillin and gentamicin for these strains ranged from 16 to 250 mug/ml (median 32 mug/ml) for oxacillin and 12 to 48 mug/ml (median 24 mug/ml) for gentamicin. The minimal bactericidal concentration of oxacillin for 50% of strains in the presence of 12, 6, 3, and 1.5 mug of gentamicin per ml, respectively, was 2, 8, 16, and 32 mug/ml. The combination of oxacillin and gentamicin at clinically attainable serum levels was synergistically bactericidal against 27/34 (80%) of these strains using strict criteria. This report reconfirms the original observation that antibiotics which affect the synthesis of bacterial cell walls combine synergistically with aminoglycosides against enterococci. This is so even though enterococci are far more resistant to oxacillin than to penicillin or ampicillin. In addition, this report suggests that the combination of oxacillin and gentamicin administered in the usual dosages includes enterococci in its bactericidal spectrum.

Drug Synergism↗

PubMed1993

Comparison of fluorescent gentamicin-thallous-carbonate and KF streptococcal agars to enumerate enterococci and fecal streptococci in meats.

Two selective and differential media were compared for their abilities to enumerate enterococci and fecal streptococci in pork, beef, and poultry products. Counts obtained on KF streptococcal (KF) agar were compared with counts obtained on fluorescent gentamicin-thallous-carbonate (fGTC) agar. Reactions of 13 known enterococcal species were also observed. All 13 species of enterococci as well as Streptococcus bovis and Streptococcus equinus grew equally well on fGTC agar. KF streptococcal medium allowed growth of most species of enterococci but not S. bovis and S. equinus. Quantitative comparisons between the two media inoculated with pure cultures of known species of enterococci revealed equivalent plate counts following incubation. However, when meat samples were plated, counts on fGTC agar were consistently and significantly higher than counts on KF agar for all sample sources.

Animals↗