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E Bingen

Publications and source records attributed to E Bingen.

At least 55 records · Page 3Linked to original sources

Microbiology of otitis media in the Paris, France, area from 1987 to 1997.

PURPOSE OF THE STUDY: To investigate epidemiologic trends in the bacteriology of acute otitis media, data were recorded during a 10-year period by the same group of investigators during clinical studies in pediatric outpatients. METHODS: Bacterial samples were obtained before antibiotic treatment from 2149 children (age 3 to 36 months) with acute otitis media. All samples were transported, handled and cultured in the same way throughout the 10-year period. RESULTS: From the study patients 1862 samples of middle ear secretion were collected by tympanocentesis and 287 samples were collected from spontaneous otorrhea occurring within 24 h. Pathogens were isolated from 70% of patients. Pathogens included Haemophilus influenzae (40%), Streptococcus pneumoniae (31%) and Moraxella catarrhalis (8%). The incidence of beta-lactamase-producing H. influenzae was approximately 20% from 1987 to 1989, was approximately 35% from 1990 to 1995 and increased to 60 and 70% during the last 2 years. The rate of S. pneumoniae with decreased susceptibility to penicillin gradually increased from 7% in 1987 to 70% in 1996 and 1997. CONCLUSION: The very high incidence of antimicrobial resistant strains reached during a short period in pediatric acute otitis media in our area, emphasizes the need for frequent epidemiologic studies.

Drug Resistance, Microbial↗

High prevalence of erythromycin resistance of Streptococcus pyogenes in Greek children.

BACKGROUND: Macrolide resistance among Streptococcus pyogenes strains is increasing in many European countries. Greece was not considered a country with high prevalence of macrolide-resistant S. pyogenes strains, and until now the genetic mechanism of resistance was unknown. METHODS: During the 25-month period from December, 1998, to December, 2000, pharyngeal cultures for S. pyogenes were performed on 743 Greek children with the clinical diagnosis of pharyngitis. The children were 1 to 16 years old (median age, 7 years) and were living in Central and Southern Greece. S. pyogenes isolates were tested for their susceptibility to erythromycin, clarithromycin, azithromycin, clindamycin, penicillin G, amoxicillin/clavulanate and cefprozil. The erythromycin-resistant isolates were further studied for their genetic mechanism of resistance by means of PCR. RESULTS: Of a total of 275 S. pyogenes isolates recovered, 105 (38%) were erythromycin-resistant (MIC > or = 1 microgram/ml) [corrected], with 54, 45 and 1% of them carrying mef(A), erm(A) [subclass erm(TR)] and erm(B) gene, respectively. The prevalence of erythromycin-resistant strains was 29 and 42% during the time periods December, 1998, to December, 1999, and January, 2000, to December, 2000, respectively. All erythromycin-resistant isolates were also resistant to clarithromycin and azithromycin. The isolates carrying the erm(A) gene were inducibly resistant to clindamycin. The 275 S. pyogenes isolates had ceprozil MICs < or = 0.032 microgram/ml. CONCLUSIONS: The current high (38%) prevalence of erythromycin-resistant S. pyogenes in Central and Southern Greece requires continuous surveillance and careful antibiotic policy.

Adolescent↗

CTX-M-type extended-spectrum beta-lactamase that hydrolyzes ceftazidime through a single amino acid substitution in the omega loop.

Escherichia coli ILT-1, Klebsiella pneumoniae ILT-2, and K. pneumoniae ILT-3 were isolated in May 1999 in Paris, France, from a rectal swab of a hospitalized 5-month-old girl. These isolates had a clavulanic acid-inhibited substrate profile that included expanded-spectrum cephalosporins. The MICs of cefotaxime were higher for E. coli ILT-1 and K. pneumoniae ILT-2 than for K. pneumoniae ILT-3, while the opposite was found for the MICs of ceftazidime. Genetic and biochemical analyses revealed that E. coli ILT-1 and K. pneumoniae ILT-2 produced the CTX-M-18 beta-lactamase, while K. pneumoniae ILT-3 produced the CTX-M-19 beta-lactamase. The amino acid sequence of the CTX-M-18 beta-lactamase differed from that of the CTX-M-9 beta-lactamase by an Ala-to-Val change at position 231, while CTX-M-19 possessed an additional Pro-to-Ser change at position 167 in the omega loop of Ambler class A enzymes. The latter amino acid substitution may explain the CTX-M-19-mediated hydrolysis of ceftazidime, which has not been reported for other CTX-M-type enzymes. The bla(CTX-M-18) and bla(CTX-M-19) genes were located on transferable plasmids that varied in size (ca. 60 and 50 kb, respectively) but that showed similar restriction patterns.

Amino Acid Sequence↗

Mechanisms of macrolide resistance in clinical pneumococcal isolates in France.

The genetic basis of macrolide resistance was investigated in a collection of 48 genotypically unrelated clinical isolates of Streptococcus pneumoniae obtained between 1987 and 1997 in France. All strains were resistant to erythromycin, clindamycin, and streptogramin B, exhibiting a macrolide-lincosamide-streptogramin B resistance phenotype, and harbored the erm(B) gene. None of the strains carried the mef(A) or erm(A) subclass erm(TR) gene.

Anti-Bacterial Agents↗

Mechanisms of macrolide resistance in clinical group B streptococci isolated in France.

Macrolide susceptibility was investigated in clinical group B streptococci obtained from neonates or pregnant women in 2000 in France. Of 490 consecutive isolates, 18% were resistant to erythromycin. The erm(B), erm(A) subclass erm(TR), and mef(A) genes were harbored by 47, 45, and 6% of these strains, respectively. Two isolates did not harbor erm or mef genes.

Anti-Bacterial Agents↗

Clonal relationship between U.S. and French serotype V group B streptococcus isolates.

We examined the genetic diversity of serotype V group B streptococcus (GBS) isolates in the Paris area and compared them with the predominant American serotype V clone. Pulsed-field gel electrophoresis yielded 11 patterns for 64 French GBS. One pattern was obtained with 60% of the isolates tested and was indistinguishable from that of the predominant American clone.

Bacterial Typing Techniques↗

Automated ribotyping provides rapid phylogenetic subgroup affiliation of clinical extraintestinal pathogenic Escherichia coli strains.

Using the automated Riboprinter system, we have initiated the construction of an electronic Riboprint database composed of 72 ECOR reference strains and 15 archetypal virulent strains in order to provide a new simple molecular characterization method. More than 90% of the ECOR strains clustered in their original phylogenetic group. All but one of the archetypal virulent strains had a profile identical to that of one of the ECOR strains and could be easily affiliated with a phylogenetic group. This method appears to be an accurate and practical tool especially for investigating the genetic relationship between clinical extraintestinal pathogenic strains and B2 subgroup ECOR strains or archetypal pathotype strains.

Bacteremia↗

[Tympanostomy tube otorrhea: microbiological epidemiology, pathogen susceptibility to local antibiotics and bactericidal power of the rifamycin-olfloxacin combination].

OBJECTIVE: We studied the microbiological epidemiology of tympanostomy tube otorrhea, rifamycin and ofloxacin sensitivity of pathogens isolated from these otorrheas, and the bactericidal power of the rifamycine-ofloxacin combination. MATERIAL AND METHODS: A prospective study was conducted in 1997 with cultures of otorrhea aspirates, in vitro study of pathogen resistance to rifamycin and ofloxacin, bacteriocidal study of the rifamycin-ofloxacin combination. RESULTS: One hundred eight aspirates were obtained from 98 children (mean age 5 years). Ten aspirates were sterile, 32 had more than one pathogen. The more frequent pathogens were Pseudomonas aeruginosa (Pa) (n=35), Staphylococcus aureus (Sa) (n=27), Haemophilus influenae (Hi) (n=12) and Streptococcus pneumoniae (Sp) (n=9). All Hi, all Sp, 86.3% of the Sa (MIC(90) 0.25 mg/l) and none of the Pa were rifamycin sensitive. All Hi, 97.7% of the Pa (MIC(90) 0.5 mg/l), 73,1% of the Sa (MIC(90) 0.24 mg/l) and none of the Sp were ofloxacin sensitive. The rifamycin-ofloxacin combination led to a 4 log CFU/ml decrease in 6 hours for Sp, and in 24 hours for Pa, Hi and Sa. CONCLUSION: The rifamycin-ofloxacin combination is bactericidal for bacteria causing tympanostomy tube otorrhea. Otic drops with this combination should be considered as the first line treatment for such otorrhea.

Anti-Bacterial Agents↗

Molecular epidemiology survey of penicillin-susceptible and -resistant Streptococcus pneumoniae recovered from patients with meningitis in France.

The genetic diversity of Streptococcus pneumoniae isolates (n=291) recovered from cerebrospinal fluid of patients with meningitis in France was investigated by restriction fragment length polymorphism analysis of the ribosomal RNA gene regions and of the pbp2b and 2x genes. Statistical analysis of the data by factorial analysis of correspondence established the following: penicillin-susceptible isolates had a high level of genetic diversity, especially those belonging to serogroups frequently associated with carriage; capsular serotype switches could occur among penicillin-susceptible and -resistant isolates; and the mechanisms of acquired penicillin resistance were clearly distinct in isolates with penicillin minimum inhibitory concentration (MIC) values <1 mg/L and isolates with penicillin MIC values >/=1 mg/L. Thus, an increase in the penicillin MIC for a given strain, from intermediate to high-level resistance would be a rare event.

Adult↗

[Pathology of Haemophilus infections: current situation in pediatrics].

Haemophilus influenzae is the main pathogen in community-acquired infections in children. Prior to the introduction of H. influenzae type b immunization (Hib), capsular type b H. influenzae was the most invasive type of H. influenzae, and was the major cause of meningitis in children in France and many developing countries. The introduction of a Hib vaccine program results in rapid and dramatic decline in the incidence of Hib infections in children. The resistance rate to beta-lactam antibiotics is slowly increasing with beta-lactamase production. Third generation cephalosporins are used for the treatment of invasive infection (meningitis etc.). The empiric treatment of otitis and respiratory tract infections in children is the combination of clavulanic acid and amoxicillin or third generation cephalosporins.

Anti-Bacterial Agents↗

Effects of oral Saccharomyces boulardii on bacterial overgrowth, translocation, and intestinal adaptation after small-bowel resection in rats.

BACKGROUND: Small-bowel resection in animals results in alterations of the morphology and functional adaptation in the remaining intestine. The aim of our study was to study the effect of Saccharomyces boulardii versus placebo in rats after 50% small-bowel resection. METHODS: Sixty-three rats were assigned to one of three groups: small-bowel resection (n = 31), transected surgery controls (n = 16), or non-surgical controls (n = 16). Of the 31 rats with small-bowel resection, 15 were given S. boulardii (140 mg/dl), and 16 were given placebo. Intestinal markers measured included bacterial overgrowth (BO) on days 4 and 8 and translocation into mesenteric lymph nodes, liver, and spleen. Markers of small-bowel adaptation included histomorphology of the mucosa, protein content, and various brush-border enzymes (sucrase, glucoamylase, n-aminopeptidase). RESULTS: In the jejunal mucosal samples on day 8, S. boulardii-treated rats showed a significant increase in protein content (58.3 +/- 12 mg/10 cm) compared with placebo-treated rats (29.2 +/- 1.8) or non-surgery controls (18.3 +/- 1.2; P < 0.001). S. boulardii-treated rats also had significantly higher levels of all three brush-border enzymes. A significant increase of enzyme-specific activities was observed in the ileum of S. boulardii resected rats compared with the placebo resected group on day 4, and no significant differences were seen in the remnant ileum except an increase in protein content in S. boulardii-treated rats on day 8. Histomorphometric studies showed no differences in ileal villus height or translocation frequencies by day 8 in S. boulardii or placebo resected rats. CONCLUSIONS: These data indicate that, after resection, S. boulardii does not modify bacterial overgrowth or translocation frequency but does significantly enhance the functional adaptation of the remaining intestinal segments.

Adaptation, Physiological↗

Genotypic characterisation of endemic VanA Enterococcus faecium strains isolated in a paediatric hospital.

A total of 36 vancomycin-resistant Enterococcus faecium isolates obtained from 30 patients during a 28-month period in a paediatric university hospital was analysed by pulsed-field gel electrophoresis (PFGE) combined with Southern hybridisation of a vanA-specific DNA probe. All the isolates hybridised with the vanA probe. Seventeen different PFGE patterns and 11 PFGE subtypes were identified among the 36 clinical isolates, and the size of probe-positive bands ranged from c. 30 to 300 kb. These data are consistent with an increase in the overall genomic diversity of vancomycin-resistant E. faecium isolates during the study period. Two periods were distinguished. The prevalence of a single clone in the initial period suggested transmission between patients in three wards. During the following period, multiple genotypes of vancomycin-resistant E. faecium were identified, indicative of multiple introductions or the dissemination of resistance genes by recombinant transposition.

Adolescent↗

Resistance to macrolides in Streptococcus pyogenes in France in pediatric patients.

A total of 1,500 recent throat isolates of Streptococcus pyogenes collected between 1996 and 1999 from children throughout France were tested for their susceptibility to erythromycin, azithromycin, josamycin, clindamycin, and streptogramin B. The erythromycin-resistant isolates were further studied for their genetic mechanism of resistance, by means of PCR. The clonality of these strains was also investigated by means of serotyping and ribotyping. In all, 6.2% of the strains were erythromycin resistant, and 3.4 and 2.8% expressed the constitutive MLS(B) and M resistance phenotypes and harbored the ermB and mefA genes, respectively; ermTR was recovered from one isolate which also harbored the ermB gene. Ten serotypes and 8 ribotypes were identified, but we identified 17 strains by combining serotyping with ribotyping. Among the eight ribotypes, the mefA gene was recovered from six clusters, one being predominant, while the ermB gene was recovered from four clusters, of which two were predominant.

Anti-Bacterial Agents↗

Rapid and simple determination of the Escherichia coli phylogenetic group.

Phylogenetic analysis has shown that Escherichia coli is composed of four main phylogenetic groups (A, B1, B2, and D) and that virulent extra-intestinal strains mainly belong to groups B2 and D. Actually, phylogenetic groups can be determined by multilocus enzyme electrophoresis or ribotyping, both of which are complex, time-consuming techniques. We describe a simple and rapid phylogenetic grouping technique based on triplex PCR. The method, which uses a combination of two genes (chuA and yjaA) and an anonymous DNA fragment, was tested with 230 strains and showed excellent correlation with reference methods.

Electrophoresis, Polyacrylamide Gel↗

Identification of regions of the Escherichia coli chromosome specific for neonatal meningitis-associated strains.

Specific virulence factors associated with the pathogenesis of Escherichia coli strains causing neonatal meningitis (ECNM), such as the K1 capsular polysaccharide, the S fimbriae, and the Ibe10 protein, have been previously identified. However, some other yet unidentified factors are likely to be involved in the pathogenesis of ECNM. To identify specialized unique DNA regions associated with ECNM virulence, we used the representational difference analysis technique. The genomes of two strains belonging to nonpathogenic phylogenetic group A of the ECOR reference collection were subtracted from E. coli strain C5, isolated from a case of neonatal meningitis. Strain C5 belongs to the phylogenetic group B2 as do the majority of ECNM. We have isolated and mapped 64 DNA fragments which are specific for strain C5 and not found in nonpathogenic strains. Of these clones, 44 were clustered in six distinct regions on the chromosome. The sfa and ibe10 genes were located in regions 2 and 6, respectively. A group of genes (cnf1, hra, hly, and prs) known to be present in a pathogenicity island of the uropathogenic strain E. coli J96 colocalized with region 6. The occurrence of these DNA regions was tested in a set of meningitis-associated strains and in a control group composed of non-meningitis-associated strains belonging to the same B2 group. Regions 1, 3, and 4 were present in 91, 82, and 81%, respectively, of the meningitis strains and in 40, 13, and 47% of the control strains. Together, these data suggest that regions 1, 3, and 4 code for factors associated with the ability of E. coli to invade the meninges of neonates.

Blotting, Southern↗

[Nosocomial infections in pediatrics. Problems and perspectives].

High incidence of nosocomial infections in children is largely explained by immunodeficiency, particularly in newborns. Central venous catheter is the main risk factor and coagulase negative staphylococcus the main pathogen in cause. Large variations of nosocomial infection incidences are observed by Nososcomial Infection Surveillance Networks and depend on the pediatric speciality. The highest rate is observed in neonatal intensive care, where incidence density of catheter-related sepsis varies from four to 23 infections for 1000 catheter-days. Local surveillance in each ward, risk factors and knowledge of bacterial epidemiology allow the development of rational preventive and therapeutic protocols. However, prophylactic use of vancomycin is dangerous and immunoglobulins are inefficient.

Catheterization, Central Venous↗

[Pediatric nosocomial diarrhea].

Nosocomial diarrhea are an important cause of childhood morbidity and mortality. Rotavirus has been recognized as the most important cause of nosocomial gastroenteritidis particularly in infants during winter months. Nosocomial diarrhea are also, caused by bacterial pathogen like Clostridium difficile, Salmonella, Shigella, Campylobacter. Clostridium difficile toxin assay should be considered for patients who are receiving antibiotics. Modifications of hygiene procedures and preventive measures are necessary in order to reduce nosocomial infection.

Adenoviridae Infections↗