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E Bingen

Publications and source records attributed to E Bingen.

At least 73 records · Page 4Linked to original sources
PubMed1999

[Escherichia coli O157:H7, an emerging pathogen].

AN EMERGING PATHOGEN: Escherichia coli O157:H7 became an important pathogen starting in the early 1980s. It has caused epidemics and sporadic cases of often bloody diarrhea which may progress to severe hemolytic and uremic syndromes or thrombotic thrombocytopenic purpura. TRANSMISSION: E. coli O157:H7 is mainly transmitted in food. Water and inter-human transmission as well as direct animal-to-man transmission has also been documented. VIRULENCE: E. coli O157:H7 can adhere tightly to the enterocyte brush border (eae gene) and produce verotoxins or Shiga-like toxins and hemolysine (ehxA gene). DIAGNOSIS: Diagnosis of E. coli O157:H7 infections is based on evidencing the germ in stools and/or by identifying the genes coding for verotoxins or by serology which increased serum titre of specific antilipopolysaccharide antibodies. TREATMENT AND PREVENTION: Anti-diarrheal drugs and antibiotics have little place in the treatment of bloody diarrhea. This public health problem, requires careful identification of animal reservoirs and improved population education in food hygiene.

Animals↗
PubMed1999

[Bacterial concentration in the cerebrospinal fluid in childhood meningitis].

OBJECTIVES: The aim of this study was to analyze the epidemiological evolution of causal germs in meningitis in children aged 1 day to 15 years and determine the relationship between pretreatment concentrations of bacteria in cerebral spinal fluid (CSF), patient age, bacterial species and bacteriological eradication. PATIENTS AND METHODS: A quantitative analysis of germs was performed in 212 children with bacterial meningitis (mean age 19.8 months). RESULTS: Bacterial counts ranged from 2.10(1) to 4.10(9) CFU/ml in CSF. Among the 212 patients, 52 (24.5%) had counts 10(7)/ml. Infants had significantly higher counts than the other age groups. Mean counts for Hoemophilus influenzoe serotype B were not different from those for Streptococcus pneumoniae but were significantly higher than for Neisseria meningitidis. Compared with initial germ counts, 98.5% of the CSF specimens were sterile at 24 and 48 hours and 100% at 72 hours. CONCLUSION: Germ counts were higher in infants.

Adolescent↗
PubMed1999

Killing activities of trovafloxacin alone and in combination with beta-lactam agents, rifampin, or vancomycin against Streptococcus pneumoniae isolates with various susceptibilities to extended-spectrum cephalosporins at concentrations clinically achievable in cerebrospinal fluid.

The killing activities of trovafloxacin alone and in combination with beta-lactam agents (extended-spectrum cephalosporins, meropenem), rifampin, or vancomycin were evaluated against 20 genotypically characterized Streptococcus pneumoniae isolates for which amoxicillin MICs were >/=4 microg/ml (cefotaxime MICs, >/=4 microg/ml for six strains) at concentrations clinically achievable in cerebrospinal fluid. At 6 h the mean killing activity of trovafloxacin alone (range, 2.6 to 2.9 log(10) CFU/ml) did not vary significantly according to the susceptibility of the strains to beta-lactam agents. The activities of trovafloxacin or vancomycin added to the beta-lactam agents and the combination trovafloxacin-vancomycin were additive or indifferent. Against the ceftriaxone-resistant isolates, the killing activity of the combination of a beta-lactam agent and trovafloxacin did not differ significantly from that of a beta-lactam agent and vancomycin.

Anti-Bacterial Agents↗
PubMed1999

Comparative in vitro activities of meropenem, imipenem, temocillin, piperacillin, and ceftazidime in combination with tobramycin, rifampin, or ciprofloxacin against Burkholderia cepacia isolates from patients with cystic fibrosis.

We evaluated the activities of meropenem, imipenem, temocillin, piperacillin, and ceftazidime by determination of the MICs for 66 genotypically characterized Burkholderia cepacia isolates obtained from the sputum of cystic fibrosis patients. In vitro synergy assays, as performed by the time-kill methodology, of two- and three-drug combinations of the beta-lactams with tobramycin, rifampin, and/or ciprofloxacin were also performed with 10 strains susceptible, intermediate, or resistant to fluoroquinolones. On the basis of the MICs, meropenem and temocillin were the most active beta-lactam agents, with MICs at which 90% of isolates are inhibited of 8 and 32 micrograms/ml, respectively. The addition of ciprofloxacin significantly enhanced the killing activities of piperacillin, imipenem, and meropenem against the 10 strains tested (P < 0.05). The best killing activity was obtained with the combination of meropenem and ciprofloxacin, with bactericidal activity of 3.31 +/- 0.36 log10 CFU/ml (P < 0.05). Compared to the activity of the two-drug beta-lactam-ciprofloxacin combination, the addition of rifampin or tobramycin did not significantly increase the killing activity (P > 0.05). The three-drug combinations (with or without ciprofloxacin) significantly enhanced the killing activities of piperacillin, imipenem, and meropenem relative to the activities of the beta-lactams used alone (P < 0.05). The combination beta-lactam-ciprofloxacin-tobramycin was the combination with the most consistently synergistic effect.

Burkholderia Infections↗
PubMed1999

The link between phylogeny and virulence in Escherichia coli extraintestinal infection.

Previous studies suggesting a link between Escherichia coli phylogenetic groups and extraintestinal virulence have been hampered by the difficulty in establishing the intrinsic virulence of a bacterial strain. Indeed, unidentified virulence factors do exist, and the susceptibility of the host to infection is highly variable. To overcome these difficulties, we have developed a mouse model of extraintestinal virulence to test the virulence of the strains under normalized conditions. We then assessed the phylogenetic relationships compared to the E. coli reference (ECOR) collection, the presence of several known virulence determinants, and the lethality to mice of 82 human adult E. coli strains isolated from normal feces and during the course of extraintestinal infections. Commensal strains belong mainly to phylogenetic groups A and B1, are devoid of virulence determinants, and do not kill the mice. Strains exhibiting the same characteristics as the commensal strains can be isolated under pathogenic conditions, thus indicating the role of host-dependent factors, such as susceptibility linked to underlying disease, in the development of infection. Some strains of phylogenetic groups A, B1, and D are able to kill the mice, their virulence being most often correlated with the presence of virulence determinants. Lastly, strains of the B2 phylogenetic group represent a divergent lineage of highly virulent strains which kill the mice at high frequency and possess the highest level of virulence determinants. The observed link between virulence and phylogeny could correspond to the necessity of virulence determinants in a genetic background that is adequate for the emergence of a virulent clone, an expression of the interdependency of pathogenicity and metabolic activities in pathogenic bacteria.

Adult↗
PubMed1999

Capillary electrophoresis-single-strand conformation polymorphism analysis for rapid identification of Pseudomonas aeruginosa and other gram-negative nonfermenting bacilli recovered from patients with cystic fibrosis.

We used capillary electrophoresis-single-strand conformation polymorphism (CE-SSCP) analysis of PCR-amplified 16S rRNA gene fragments for rapid identification of Pseudomonas aeruginosa and other gram-negative nonfermenting bacilli isolated from patients with cystic fibrosis (CF). Target sequences were amplified by using forward and reverse primers labeled with various fluorescent dyes. The labeled PCR products were denatured by heating and separated by capillary gel electrophoresis with an automated DNA sequencer. Data were analyzed with GeneScan 672 software. This program made it possible to control lane-to-lane variability by standardizing the peak positions relative to internal DNA size markers. Thirty-four reference strains belonging to the genera Pseudomonas, Brevundimonas, Burkholderia, Comamonas, Ralstonia, Stenotrophomonas, and Alcaligenes were tested with primer sets spanning 16S rRNA gene regions with various degrees of polymorphism. The best results were obtained with the primer set P11P-P13P, which spans a moderately polymorphic region (Escherichia coli 16S rRNA positions 1173 to 1389 [M. N. Widjojoatmodjo, A. C. Fluit, and J. Verhoef, J. Clin. Microbiol. 32:3002-3007, 1994]). This primer set differentiated the main CF pathogens from closely related species but did not distinguish P. aeruginosa from Pseudomonas alcaligenes-Pseudomonas pseudoalcaligenes and Alcaligenes xylosoxidans from Alcaligenes denitrificans. Two hundred seven CF clinical isolates (153 of P. aeruginosa, 26 of Stenotrophomonas maltophilia, 15 of Burkholderia spp., and 13 of A. xylosoxidans) were tested with P11P-P13P. The CE-SSCP patterns obtained were identical to those for the corresponding reference strains. Fluorescence-based CE-SSCP analysis is simple to use, gives highly reproducible results, and makes it possible to analyze a large number of strains. This approach is suited for the rapid identification of the main gram-negative nonfermenting bacilli encountered in CF.

Cystic Fibrosis↗
PubMed1999

Characterization of extended-spectrum beta-lactamase-producing Salmonella typhimurium by phenotypic and genotypic typing methods.

During 1994, 10 isolates of extended-spectrum beta-lactamase-producing Salmonella typhimurium were recovered from children transferred to our hospital from two different centers. Two additional isolates were recovered from two nurses from one of these centers. The aim of this study was to determine if there is any relationship between these isolates. The characterization was done by phenotypic and genotypic methods: biotyping, phage typing, antibiotic susceptibility pattern determination, plasmid analysis, ribotyping (by the four endonucleases EcoRI, SmaI, BglII, and PvuII), pulsed-field gel electrophoresis (PFGE) of genome macrorestriction patterns with XbaI, and randomly amplified polymorphic DNA (RAPD) pattern determination (with the three primers 217 d2, B1, and A3). The same biotype, the same serotype, and an identical antibiotype were found. All isolates were resistant to oxyimino-beta-lactams, gentamicin, tobramycin, and sulfamethoxazole-trimethoprim. All isolates showed an indistinguishable pattern by ribotyping and very similar patterns by PFGE and RAPD. The overall results indicated the spread of a closely related strain of S. typhimurium in children and nurses.

Bacterial Typing Techniques↗
PubMed1999

[PCR SSCP study of an echovirus 30 meningitis outbreak].

Between April and October 1997, 21 children of 4 days to 13 years old were admitted to the Pedatric Unit of Aulnay Sous Bois's Hospital for viral meningitidis. The number of white blood cells in the cerebrospinal fluid (CSF) was between 1 and 612 cells/mm3, with, on an average, 56% of segmented cells, 34% lymphocytes and 34% monocytes. Proteins and glucose of CSF were standard. One CSF was normal. Viral meningitidis was confirmed by viral culture of CSF onto MRC5. Enterovirus were identified by direct immunofluorescence (Monoclonal Mouse Anti-Enterovirus, Dako). Serotyping (Enterovirus antisera, Eurobio, Trousses 4) identified an echovirus 30 in all cases. A highly conserved 154 bp sequence at the 5'non-coding region was studied by reverse transcription-polymerase chain reaction (RT-PCR) followed by single-strand conformation polymorphism (SSCP) (GenPhor, Pharmacia) analysis. Two dominant SSCP patterns were observed: the first contained 4/21 strains and the other 10/21 strains. The SSCP patterns of the 7 other strains were different. These results show that 2 echovirus 30 dominant clones were responsible of viral meningitidis admitted to the Pediatric Unit of Aulnay Sous Bois's hospital, between april and october 1997. The PCR-SSCP of the 5'non-coding region of echovirus 30 is a convenient, simple, reproducible epidemiologic method and it's easily applicable in a general hospital.

Adolescent↗
PubMed1998

[Microbiology in acute otitis media].

Acute otitis media is the most common bacterial infection in the child under 5 years of age and the leading reason for antibiotic prescriptions in Western countries. The choice of optimal antibiotic treatment is based essentially on microbiologic epidemiologic studies. The bacteria most often responsible for otitis belong to the commensal flora of the nasopharynx. French studies using paracentesis show that the main bacteria responsible for acute otitis media are H. influenzae, S. pneumoniae and M. catarrhalis. The epidemiology of resistance to antibiotics has recently changed, with the appearance of pneumococcal strains having reduced sensitivity to penicillin, and which have played a major role in treatment failures.

Acute Disease↗
PubMed1998

[New spectra of resistance of the main bacteria of the respiratory tract].

Management of acute pneumonia requires knowledge of current etiologic agents. Haemophilus influenzae and Streptococcus pneumoniae are the main responsible pathogens. Changes in epidemiology particularly occur in the susceptibility of antibiotics to S pneumoniae which is the main target of antimicrobial therapy.

Anti-Bacterial Agents↗
PubMed1998

[Escherichia coli virulence factors in pediatric urinary tract infections].

As many as 90% of all community-acquired urinary tract infections (UTIs) and more than 30% of nosocomially acquired UTIs are caused by E coli. The migration of bacteria into proximal urethra and bladder mucosa requires that the organisms travel "upstream" and resist being carried away by the flow of urine. Colonisation requires binding of specific adhesions of the bacteria to appropriate receptors on the surfaces of the epithelial cells. P fimbrae are found in 80%, 30% and 20% of strains from patients with pyelonephritis, cystitis and asymptomatic bacteriura, respectively. P fimbrae are found in only 30% of strains isolated from patients with pyelonephritis associated with compromising host factors such as vesicoureteral reflux, urinary tract anatomical abnormalities and recent urinary tract instrumentation.

Bacterial Adhesion↗
PubMed1998

Phylogenetic analysis of Escherichia coli strains causing neonatal meningitis suggests horizontal gene transfer from a predominant pool of highly virulent B2 group strains.

Phylogenetic relationships of 69 neonatal meningitis Escherichia coli strains isolated worldwide were studied. Restriction fragment length polymorphism of rrn operons (rrn RFLP) in these isolates was compared with that of the 72 strains of the ECOR reference collection. Distributions of K1 antigen, of polymerase chain reaction-detected ibe10 gene, pap, afa, sfa/foc, hly, and aer operons, and of a 14.9-kb rrn-containing HindIII fragment previously associated with neonatal meningitis were compared. Oligoclonality was observed for the meningitis strains. Factorial analysis of correspondence on the rrn RFLP data showed a frequency gradient of meningitis strains from the phylogenetic B2 group (68%) to the A group (6%), via the D and B1 groups (26%). The distribution of the virulence determinants argues for their horizontal transfer during the evolution of E. coli. Analysis of the status of some neonates further suggests that neonatal meningitis results from a balance between bacterial genes of virulence and host factors.

Bacterial Typing Techniques↗
PubMed1998

Comparative in vitro killing activities of meropenem, imipenem, ceftriaxone, and ceftriaxone plus vancomycin at clinically achievable cerebrospinal fluid concentrations against penicillin-resistant Streptococcus pneumoniae isolates from children with meningitis.

The activities of meropenem, imipenem, ceftriaxone, and vancomycin were evaluated against 80 penicillin-susceptible and -resistant Streptococcus pneumoniae strains. Meropenem, imipenem, ceftriaxone, and vancomycin MICs at which 90% of the isolates are inhibited were 0.5, 0.25, 1, and 0.25 microg/ml, respectively. Against penicillin-resistant strains, the best killing activity at cerebrospinal fluid concentrations was obtained with imipenem and ceftriaxone-vancomycin. However, while the killing activity of imipenem was significantly greater than that of meropenem, no significant difference was observed between the activities of meropenem and ceftriaxone-vancomycin.

Anti-Bacterial Agents↗
PubMed1998

Molecular epidemiology of ampicillin-resistant non-beta-lactamase-producing Haemophilus influenzae.

Resistance to ampicillin without beta-lactamase production is not a frequent occurrence among Haemophilus influenzae strains. This kind of resistance is encountered in unencapsulated strains isolated from bronchial secretions and ear, nose, and throat specimens and is exceptional in H. influenzae type b. We studied 29 of these strains from various areas in France and 2 reference strains. Strains were compared by using ribotyping, arbitarily primed PCR with two primers, and pulsed-field gel electrophoresis. Each technique enabled the identification of 20 to 23 different patterns among the 31 strains. The combination of the different patterns for the strains obtained by the different techniques provided 27 distinct profiles. According to these results, it seems that the clonal propagation of these resistant strains does not occur.

Adolescent↗
PubMed1998

Enteroaggregative, Shiga toxin-producing Escherichia coli O111:H2 associated with an outbreak of hemolytic-uremic syndrome.

Shiga toxin-producing Escherichia coli O111:H2 strains from an outbreak of hemolytic-uremic syndrome showed aggregative adhesion to HEp-2 cells and harbored large plasmids which hybridized with the enteroaggregative E. coli probe PCVD432. These strains present a novel combination of virulence factors and might be as pathogenic to humans as the classic enterohemorrhagic E. coli.

Bacterial Adhesion↗