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Double-blind report on the efficacy of lactic acid-producing Enterococcus SF68 in the prevention of antibiotic-associated diarrhoea and in the treatment of acute diarrhoea.

A multicentre double-blind, placebo-controlled clinical trial, involving 123 patients at 10 centres, was carried out to assess the efficacy of a preparation of lactic acid-producing Enterococcus SF 68 in the prevention of antibiotic-associated diarrhoea and in the treatment of acute diarrhoea. In the prevention study, 45 patients being treated with antibiotics were given, concurrently, one capsule twice daily of either Enterococcus SF68 or placebo. Acute diarrhoea was present in 78 patients who were given the same treatment but three times daily. All treatments were continued for 7 days. Enterococcus SF 68 was shown to be effective in reducing the incidence of antibiotic-associated diarrhoea in comparison with placebo (8.7% compared with 27.2%, respectively). Patients with acute enteritis showed a significantly faster resolution of bowel abnormalities during treatment with Enterococcus SF68 compared with placebo.

Adult↗

PubMed1990

In vitro activity of daptomycin-metronidazole combinations against mixed bacterial cultures: reduced activity of metronidazole against Bacteroides species in the presence of Enterococcus faecalis.

The in vitro activity of daptomycin-metronidazole combinations against mixed cultures of gram-positive facultative cocci and strains of the Bacteroides fragilis group was investigated. Metronidazole did not influence the high activity of daptomycin against strains of Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis in the absence or presence of the co-cultured Bacteroides strains. In contrast, the Enterococcus faecalis isolates protected the co-cultured Bacteroides strains against the killing effect of metronidazole, even at a concentration four- or eightfold the MIC of metronidazole. Killing curve experiments confirmed this protective effect of different isolates of Enterococcus faecalis.

Anti-Bacterial Agents↗

PubMed1990

Isolation of three strains of beta-lactamase-producing Enterococcus faecalis in Argentina.

Of the 90 strains of Enterococcus spp. isolated in an Argentine laboratory in the period from January to July 1989, three were identified as beta-lactamase-producing Enterococcus faecalis. According to the literature reviewed, these appear to be the first beta-lactamase-positive strains of Enterococcus isolated outside the USA. They differed from most beta-lactamase-producing strains already described in that they were susceptible to low concentrations of macrolides. All three strains were resistant to high concentrations of aminoglycosides.

Aminoglycosides↗

PubMed1995

Emerging multiply resistant enterococci among clinical isolates. I. Prevalence data from 97 medical center surveillance study in the United States. Enterococcus Study Group.

To assess the evolving problem of therapeutic drug resistances among enterococci, we organized a comprehensive national (United States) surveillance trial using 99 recruited microbiology laboratories in 48 of the 49 contiguous states or districts. All but two sites completed the protocol that generated information from nearly 2000 enterococci, usually isolated from blood cultures. All strains were speciated by the same method (API 20S) and were susceptibility tested by three methods (broth microdilution, disk diffusion, and Etest) against ampicillin, penicillin, vancomycin, teicoplanin, gentamicin, and streptomycin. Strains resistant to a glycopeptide or penicillin, or possessing high-level aminoglycoside resistance were referred to the monitor's laboratory for validation and additional susceptibility testing against other alternative antimicrobial agents. The most common species were Enterococcus faecalis and Enterococcus faecium. However, antimicrobial resistance occurred most often among the E. faecium isolates. Twenty-three percent of participant centers (22 sites) reported 87 vancomycin-resistant isolates, which accounts for 4.4% of the isolates evaluated. A recent audit (March 1994) of the laboratories not reporting vancomycin resistance during the study interval (October-December 1992) revealed that 61% of sites have now recognized these strains, a threefold increase in 12-15 months. Teicoplanin remained active against 28% (Van B phenotype) of vancomycin-resistant enterococci (10 E. faecalis, 13 E. faecium, and one Enterococcus spp.). Ampicillin-resistant beta-lactamase-positive strains were found only at one medical center (two strains, 0.2% of referred or validated strains); however, ampicillin-resistant strains represented 12% of all enterococcal, but nearly 60% of E. faecium strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗

PubMed1992

Enterococcus species in urinary tract infection.

Significant urinary isolates have been prospectively recorded since 1971. Enterococcus species, a common cause of nosocomial urinary tract infection, have been identified, and susceptibilities to a range of antibiotics have been determined. In addition, isolates in 1988 were tested for breakpoint susceptibility to vancomycin and teicoplanin. Despite changes in the hospitals covered, isolation of Enterococcus species rose steadily from 4% in 1971 to 12.6% in 1990 in hospital patients and from 2% to 5.6% in general-practice patients (P less than .01). All isolates of Enterococcus species were sensitive to ampicillin. Teicoplanin inhibited all 526 strains tested at a concentration of 2 micrograms/mL, but the same concentration of vancomycin inhibited only 370 (70%). The increased prevalence of enterococcal urinary tract infection is probably the result of increasing use of catheterization and broad-spectrum antibiotics. Glycopeptides reach high levels in the urine, and teicoplanin might be an alternative for the treatment of urinary tract infections due to enterococci.

Anti-Bacterial Agents↗

PubMed1995

A survey of antimicrobial susceptibility of clinical isolates of Enterococcus spp. from Irish hospitals.

Nosocomial enterococcal infections are increasing. In order to establish the species distribution and antibiotic resistance patterns of enterococci in clinical specimens from hospitalized patients, we undertook a survey of 23 Irish hospitals. One thousand and five viable enterococcal strains were studied. Nine different species of enterococci were identified, including Enterococcus faecalis (84%); Enterococcus faecium (9%); and Enterococcus hirae (3%). The most common sites of isolation were the urinary tract (66%), wound and soft tissues (23%) and blood stream (3%). Many of the isolates were multiply antibiotic resistant. Ampicillin resistance was detected in 16%. Neither beta-lactamase production, nor high level penicillin resistance was detected. High level gentamicin resistance was evident in 7% of isolates and varied among species, e.g. 4% E. faecalis, 24% E. faecium, and 34% E. hirae. A number of isolates (23%) were also highly resistant to streptomycin. No clinically significant glycopeptide resistance was detected. The species distribution and incidence of multiple resistance was geographically widespread. This emphasizes the need for detailed speciation and in-vitro susceptibility testing along with the evaluation of alternative combination chemotherapeutic regimens for the management of serious enterococcal infection.

Anti-Bacterial Agents↗

PubMed1985

The phylogenetic position of Streptococcus and Enterococcus.

Streptococcus pyogenes, S. equinus, S. bovis, S. salivarius, S. sanguis, S. mutans, S. rattus, S. cricetus, S. lactis, S. raffinolactis and Enterococcus faecalis have been characterized by oligonucleotide cataloguing of their 16S ribosomal RNA. All the organisms form a loose but coherent group that is phylogenetically equivalent to those of lactobacilli, bacilli, the Brochothrix and Listeria group, and related taxa that constitute one of several sublines within the 'Clostridium' branch of Gram-positive eubacteria. Within the Steptococcus-Enterococcus group, organisms fall into three moderately related clusters defined by Enterococcus, the lactic acid streptococci and streptococci of the pyogenic and oral groups, respectively.

Animals↗

PubMed1992

Vancomycin resistance gene vanC is specific to Enterococcus gallinarum.

Nearly all strains of Enterococcus gallinarum are resistant to low levels of vancomycin. The glycopeptide resistance gene vanC from E. gallinarum BM4174 has recently been cloned and sequenced. A probe specific for vanC hybridized with a 2.7-kb EcoRI and a 4.5-kb HindIII fragment of total DNA from the 42 strains of E. gallinarum studied. No homology was detected with DNA of strains belonging to other species intrinsically resistant to vancomycin, including Enterococcus casseliflavus, a species that expresses a vancomycin resistance phenotype similar to that of E. gallinarum. No hybridization with DNA of enterococcal strains with acquired resistance to high or low levels of vancomycin was observed. The specificity of the vanC probe allowed us to distinguish E. gallinarum from 12 other species of enterococci, indicating that this probe is a useful tool for species identification within the genus Enterococcus.

Culture Media↗

PubMed1970

Effect of pH of medium and size of inoculum on activity of antibiotics against group D Streptococcus (Enterococcus).

Seventy-one clinical isolates of 5 species of group D Streptococcus (Enterococcus) were tested for susceptibility to 15 antibiotics at pH 5.0, 7.4, and 8.5. Penicillin G, ampicillin, cephalothin, cephaloridine, and novobiocin were considerably more active against all strains at pH 5.0 than in the more alkaline media. On the other hand, lincomycin, clindimycin, erythromycin, and gentamicin were moderately to markedly more active at pH 8.5. No important differences were noted in the susceptibility of the strains to kanamycin and streptomycin, at the pH levels tested, but the organisms were quite resistant to them in these tests. The various species differed quantitatively in their susceptibility to the individual drugs and in the effects of pH. The size of the inoculum also had a variable effect on susceptibility, depending on the species of Enterococcus, the antibiotics, and the pH of the test medium. The data suggest that, in the antibiotic treatment of urinary tract infections caused by Enterococcus, attempts should be made to achieve the optimum pH in the urine, particularly in view of the fact that organisms of this group are often resistant to several antibiotics in the usual tests.

Anti-Bacterial Agents↗

PubMed1991

Ampicillin-resistant Enterococcus raffinosus in an acute-care hospital: case-control study and antimicrobial susceptibilities.

A prospective study identified 9 (32%) of 28 ampicillin-resistant (MIC greater than or equal to 16 micrograms/ml) enterococcus isolates as Enterococcus raffinosus. A case-control study found no significant differences with respect to underlying diseases, catheterization, or surgery between patients with ampicillin-resistant E. raffinosus and those with ampicillin-susceptible Enterococcus spp. Prior treatment with antibiotics and prolonged hospitalization were more frequent among patients with ampicillin-resistant E. raffinosus. Patients with the same strain (determined by plasmid analysis) were frequently hospitalized concurrently.

Aged↗

PubMed1995

Correlation between phenotypic characteristics and DNA relatedness within Enterococcus faecium strains.

We noted that a number of enterococcal strains isolated from human clinical specimens resembled Enterococcus faecium but were able to produce acid from glycerol, raffinose, and/or sorbitol, while others failed to form acid from mannitol. An additional concern was that many of these strains with atypical phenotypic characteristics also appeared to acquire vancomycin resistance. In order to determine if such atypical strains were variants of E. faecium or new Enterococcus species, 35 E. faecium or E. faecium-like strains (grouped into 10 phenotypes on the basis of the results of the following tests: capacity to form acid from glycerol, mannitol, raffinose, or sorbitol and susceptibility to vancomycin) and four strains of Enterococcus faecalis were taken from our culture collection, analyzed for their whole-cell protein profiles by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and identified to the species level by DNA-DNA reassociation experiments. All E. faecium-like strains, including four mannitol-negative variants, conformed to at least two of three DNA-DNA relatedness criteria: they were 70% or more related to the type strain of E. faecium at optimal conditions, they had less than 5% divergence within the related sequences, and they had a relatedness of 60% or greater under stringent conditions. The protein profiles of atypical strains were similar to those of typical strains and were easily distinguishable from those of E. faecalis and other enterococcal species. The five E. faecalis strains were 12 to 16% related to the E. faecium type strain. These results indicate that the phenotypic description of E. faecium should include all of these variable characteristics.

Bacterial Proteins↗

PubMed2025

The NagY antiterminator in Enterococcus faecalis: a novel regulatory mechanism and its impact on cell metabolism.

The Enterococcus genus is the most controversial group of lactic acid bacteria. While some strains are used as probiotics, other species, including Enterococcus faecalis, are responsible for health-related pathologies. Under conditions of infection, the N-acetylglucosamine metabolism of E. faecalis undergoes significant changes in expression, even more important than those of virulence factors. This metabolism is mediated by the nagY-nagE operon, which is regulated by the transcriptional antiterminator NagY. In this report, we focus on the regulatory mechanism of NagY and its impact on bacterial metabolism. We showed that NagY requires the interaction with the RNase III to achieve optimal induction of its own expression by cleaving the 5' untranslated region of the nagY mRNA. The NagY regulon was identified and the central role of the antiterminator in the E. faecalis metabolism was demonstrated, highlighting its importance in the opportunistic nature of the bacterium. This study provides a valuable advance in the understanding of regulation and the importance of post-transcriptional actors in E. faecalis adaptation.IMPORTANCEAs a commensal, Enterococcus faecalis colonizes the gastrointestinal tract of 31 to 80% of the intestinal microbiota in adults and is considered ubiquitous, due to its strong environmental stress resistance capabilities. However, in immunocompromised patients, the poorly understood transition from commensal to opportunistic pathogen occurs, and many studies suggest that the metabolism plays a central role in this process. In this study, we focus on the regulator NagY, which is involved in the metabolism of N-acetylglucosamine, an important carbon source for bacterial pathogens in the human host. We characterized a novel regulatory mechanism involving the NagY antiterminator and the ribonuclease RNase III. In addition, we identified the target genes of the regulator, through which we were able to demonstrate that NagY has a strong impact on the metabolism of β-glucosides. Overall, this work highlights the importance of regulation of the bacterial metabolic adaptation in the host.

Enterococcus faecalis↗

PubMed1992

Aminoglycoside-resistant Streptococcus and Enterococcus species isolated from bovine mammary secretions.

A total of 117 isolates representing four Streptococcus species and 20 isolates representing two Enterococcus species from bovine mammary secretions were examined for resistance to streptomycin, kanamycin, and gentamicin. Resistance to streptomycin (85.4%) was most prevalent, followed by kanamycin (19%) and gentamicin (2.2%). Minimum inhibitory concentration of streptomycin for most organisms examined ranged from 16 to 250 micrograms/ml. For kanamycin, the minimum inhibitory concentration for most organisms was .5 to 62.5 micrograms/ml. Minimum inhibitory concentration for gentamicin was lower than for kanamycin. Two strains each of Streptococcus uberis and Enterococcus faecalis had minimum inhibitory concentration for streptomycin of greater than 2000 micrograms/ml, and two strains of E. faecalis had similar minimum inhibitory concentration for kanamycin. The minimum bactericidal concentration for all organisms was one to four times higher than minimum inhibitory concentration. None of the organisms evaluated was found to carry plasmids. Transfer of antibiotic resistance in plasmid-free strains was not achieved by mobilization with the aid of plasmid pAD1, indicating the absence of conjugative transposons. These data suggest that expression of aminoglycoside resistance of Streptococcus and Enterococcus species of bovine origin is likely due to factors other than plasmids or conjugative transposons.

Animals↗

PubMed1992

Hospital-acquired infection with vancomycin-resistant Enterococcus faecium transmitted by electronic thermometers.

OBJECTIVES: To describe an epidemic of vancomycin-resistant Enterococcus faecium causing bacteremia and bacteriuria, to identify the source of infection, to delineate risk factors associated with acquisition of the organism, and to determine antibiotic sensitivities for the organism. DESIGN: Investigation of an epidemic, including a case-control study. SETTING: Medical-surgical intensive care unit and ward in a university medical center. PATIENTS: Nine patients infected or colonized with vancomycin-resistant Enterococcus faecium and 20 noninfected controls. MEASUREMENTS: Clinical data, environmental surveillance cultures, and in-vitro microbiologic studies. RESULTS: Colonization or infection by vancomycin-resistant E. faecium was associated with an increased duration of treatment with ceftazidime, 13.2 compared with 4.6 days, and a greater number of nonisolated days of hospitalization in the intensive care unit, 19.9 compared with 6.4 days for infected and noninfected patients, respectively (P less than 0.05). Environmental surveillance cultures recovered the organism repeatedly from the rectal probe handles of three electronic thermometers used exclusively on nonisolated patients in the intensive care unit. Restriction endonuclease analysis of plasmid DNA showed that all clinical and environmental isolates were identical. Infection control measures, including isolation of colonized or infected patients and removal of the rectal thermometer probes suspected to be responsible for transmission, resulted in termination of the outbreak. In-vitro, time-kill studies showed that the combination of ciprofloxacin, rifampin, and gentamicin resulted in bactericidal activity against the organism. CONCLUSIONS: This nosocomial outbreak of infection due to a highly vancomycin-resistant strain of Enterococcus is the first epidemic in which an electronic thermometer has been implicated as the vehicle of transmission for an infectious agent.

Adolescent↗

PubMed1991

[Study of the host factors in the occurrence of the postoperative infections--special reference to the pathogenicity of the Enterococcus and MRSA].

A study of the pathogenicity of the Enterococcus and Methicillin resistant S. aureus (MRSA) was made of 781 cases with gastroenterological surgery. The results obtained were summarized as follows. In this study 215 strains were isolated from clinical specimens. In these strains 13% was isolated from the postoperative mixed infection and only 7% occurred in single infection. Most of the single infections by the Enterococcus occurred in the cases with changes in host resistance, such as terminal cancer, disorder of the glucose tolerance, malnutrition and/or organ failures. Seventy-three strains were isolated from clinical specimens. In these strains 10% were the postoperative mixed infection and 40% were single infection. Incidence of the infection by the MRSA was significantly high compared with that by the Enterococcus. Single infection by the MRSA occurred even in the cases with normal host resistance. Strains producing enterotoxin C (single or plus A) were frequently isolated in MRSA enteritis or pneumonia. However, 60 percent of the patients in whom MRSA were detected in their abdominal drains had no signs of infection. These results suggest that the occurrence and severity of the MRSA infection relate with site of the infection and production of the exotoxin.

Enterococcus↗

PubMed1995

Characterisation and antimicrobial susceptibility of Enterococcus species from the intestines of ducks in Assam.

The Enterococcus flora of duck intestines consisted of E faecalis and E faecium in ducklings less than eight weeks old and E faecalis, E faecium and E gallinarum in ducks more than eight weeks old. The enterococci were resistant to several antibiotics; chloramphenicol and gentamycin sulphate were the only antibiotics of those tested which were moderately effective. All the Enterococcus species isolates were resistant to the macrolide and lincosamide antibiotics.

Age Factors↗

PubMed1990

Enterococcus columbae, a species from pigeon intestines.

Gram-positive cocci which dominate in the intestinal flora of domestic pigeons were found to constitute a new species of the genus Enterococcus. The strains were most closely related to Enterococcus cecorum, originally described as Streptococcus cecorum, a carboxyphilic species from chicken intestines, and to Enterococcus avium. The pigeon strains resemble E. cecorum and also many E. avium strains in their lack of group D antigen and in being more sensitive to NaCl than other enterococci. The type strain is strain STR 345 (= NCIMB 13013).

Amino Acid Sequence↗

PubMed1990

Pathogenicity of the enterococcus in surgical infections.

The enterococcus has been relegated to a position of unimportance in the pathogenesis of surgical infections. However the increasing prevalence and virulence of these bacteria prompt reconsideration of this view, particularly because the surgical patient has become increasingly vulnerable to infectious morbidity due to debility, immunosuppression, and therapy with increasingly potent antibiotics. The enterococcus is a versatile opportunistic nosocomial pathogen, causing such diverse infections as wound, intra-abdominal, and urinary tract infections; catheter-associated infection; suppurative thrombophlebitis; endocarditis; and pneumonia. Although surgical drainage remains the cornerstone of therapy for enterococcal infections involving a discrete focus, in the circumstances typified by the compromised surgical patient, specific antibacterial therapy directed against the enterococcus is warranted. Recent evidence indicates that parenteral antibiotic therapy for enterococcal bacteremia is mandatory and that appropriate therapy clearly reduces the number of deaths.

Cross Infection↗