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Streptococcus pneumoniae is an uncommon cause of osteoarticular infections (OAI) in children. The objective of this study was to investigate the clinical and laboratory characteristics of pneumococcal OAI before and after the introduction of the heptavalent pneumococcal conjugate vaccine (PCV7). Data were retrospectively collected from children aged <16 years who were hospitalized for pneumococcal OAI between 1997 and 2007 in four Parisian teaching hospitals. Forty-three children were included (32 with arthritis and 11 with osteomyelitis) and the median age of these children was 12.5 months (range 3 months to 14 years). Serotypes were available for 19/43 strains (44 %) from 1997 onwards and for 12/13 strains (92 %) from 2005 onwards. Seven unvaccinated children were infected with vaccine serotypes and we observed only one vaccine failure. After the introduction of PCV7, we noted an increase in short-term complications and the emergence of serotype 19A, which was penicillin-intermediate in 86 % of cases. After PCV7 introduction, serotype 19A was the most frequent serotype implicated in pediatric pneumococcal OAI. The 13-valent pneumococcal conjugate vaccine introduced in France in June 2010 should cover the emerging serotype. [ABSTRACT FROM AUTHOR]

Nosocomial outbreaks of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae are an increasing concern in neonatal intensive care units (NICUs). We describe an outbreak of ESBL-producing K. pneumoniae that lasted 5 months and affected 23 neonates in our NICU. Proton pump inhibitor and extended-spectrum cephalosporin exposure were significantly associated with the risk of ESBL-producing K. pneumoniae colonisation and/or infection. Thirty isolates recovered from clinical, screening and environmental samples in the NICU were studied by means of Raman spectroscopy, pulsed-field gel electrophoresis and repetitive extragenic palindromic polymerase chain reaction (rep-PCR). The Raman clustering was in good agreement with the results of the other two molecular methods. Fourteen isolates belonged to the Raman clone 1 and 16 to the Raman clone 3. Molecular analysis showed that all the strains expressed SHV-1 chromosomal resistance, plasmid-encoded TEM-1 and CTX-M-15 β-lactamases. Incompatibility groups of plasmid content identified by PCR-based replicon typing indicated that resistance dissemination was due to the clonal spread of K. pneumoniae and horizontal CTX-M-15 gene transfer between the two clones. [ABSTRACT FROM AUTHOR]

Acute respiratory tract infections (ARTIs) are the main reason for antibiotic prescription in children. In 2005, the French Drug Agency published guidelines to minimise inappropriate use of antibiotics for ARTI. The purpose of this study was to assess the impact of implementing these guidelines in a paediatric emergency department. We retrospectively analysed data collected prospectively in a French paediatric emergency department from November 2005 (date of guideline implementation) to October 2009. For each child diagnosed with ARTI, we collected age, diagnosis, and prescribed antibiotics. We computed antibiotic prescription rates in the study population. During the study period, 53,055 children were diagnosed with ARTI and 59% of the 22,198 antibiotic prescriptions given at discharge were related to ARTI. The proportion of ARTI patients given antibiotic prescriptions fell from 32.1% during the first year to 21% in year 4 ( p < 10, Cochran-Armitage test). Amoxicillin-clavulanic acid and amoxicillin accounted for 50% and 34% of antibiotic prescriptions for ARTI, respectively. French antibiotic guidelines led to significant decreases in antibiotic prescription for ARTI in our paediatric emergency department. [ABSTRACT FROM AUTHOR]

In January 1996 the emergence of penicillin-susceptible, multiresistant serotype 6B Streptococcus pneumoniae isolates resistant to chloramphenicol, tetracycline, erythromycin, clindamycin and trimethoprim-sulfamethoxazole was observed in young carriers in the city of Patras, located in the southwestern region of Greece. Later, a significant spread of pneumococci with this unusual phenotype was noted in carriers living in various other areas of the country. Using restriction fragment length polymorphism of the ribosomal RNA genes, clonal relationships were found between these Greek strains and serotype 6B penicillin-susceptible, multiresistant pneumococci isolated in France between January 1992 and September 1996. The French and Greek isolates appear to have a common ancestry. [ABSTRACT FROM AUTHOR]

In the evaluation of treatment failure in group A streptococcal pharyngitis, it is essential to distinguish persistence or relapse with homologous streptococcal strains from the acquisition of new, unrelated strains. Randomly amplified polymorphic DNA analysis and restriction fragment length polymorphism analysis of total DNA were used as epidemiological tools to compare 122 pre- and post-treatment Streptococcus pyogenes isolates obtained from 61 patients. The results obtained by molecular typing showed that bacteriological failures were due to the original strains in 43 cases (70%) and to new strains in 18 cases (30%). In the present study, restriction fragment length polymorphism analysis of total DNA appeared to be more discriminative than randomly amplified polymorphic DNA analysis. Thus, molecular analysis of DNA is an effective way to distinguish recurrence from persistence or relapse and will be useful in assessing the efficacy of new antibiotic treatments. [ABSTRACT FROM AUTHOR]

Time-kill kinetic studies were used to measure the bactericidal activity of amoxicillin/clavulanic acid (in a new form for pediatric use), cefaclor, cefuroxime, cefixime and erythromycin against 30 beta-lactamase producing Moraxella catarrhalis strains. Antibiotics were tested at the mean maximum serum concentration observed after administration of a standard dose and at 0.5 × Cmax, 0.33 × Cmax and 0.25 × Cmax. A 2 log10 reduction in colony counts was obtained with the Cmax of amoxicillin/clavulanic acid and cefixime after 5 h of incubation. After 24 h of incubation a decrease of 3 and 4 log was observed with cefixime and amoxicillin/clavulanic acid respectively. At 0.5 × Cmax and 0.33 × Cmax, bactericidal activity was obtained only with amoxicillin/clavulanic acid. [ABSTRACT FROM AUTHOR]

A dynamic in vitro model was used to determine the killing kinetics of daptomycin against 15 vancomycin-resistant clinical isolates of Enterococcus faecium. Concentration profiles simulating those observed in serum following administration of both low-dose (2 mg/kg) and high-dose (6 mg/kg) daptomycin were bactericidal within 5.5 and 2.8 h, respectively. In contrast, when albumin was added to the growth medium, the corresponding bacterial killing times were slowed to>24 h and 7 h; these results suggest that in the clinical setting, daptomycin dosages of approximately 6 mg/kg are required to achieve bactericidal activity against vancomycin-resistant Enterococcus faecium. [ABSTRACT FROM AUTHOR]

Eighty-five cerebrospinal fluid (CSF) specimens from the same number of pediatric patients with meningitis were examined to determine the bacterial count and the relationship of this count to the microscopy results, the ages of the patients and the bacterial species isolated. Bacterial counts ranged from 2 × 10 to 4 × 10 CFU/ml CSF. Twenty-five percent of the 85 CSF specimens positive for Haemophilus influenzae type b, Neisseria meningitidis, Streptococcus pneumoniae, Escherichia coli K1 and group B streptococci had counts of 10 CFU/ml or higher. Children between 1 and 6 months of age had significantly higher counts (p < 0.05) than the other age groups. The three patients who had positive CSF cultures 24 h after the start of therapy all had initial bacterial counts of 10 CFU/ml or higher. The detection limit for Gram stain/microscopy was 10 CFU/ml. No correlation was found between bacterial count and the number of polymorphonuclear leukocytes. [ABSTRACT FROM AUTHOR]

The killing kinetics of cefuroxime against 25 Streptococcus pneumoniae isolates with penicillin MICs of <0.1, 0.1-1.0 and 2 mg/l were studied in an in vitro model simulating the serum concentration profile in healthy adults following a single intramuscular injection of 500 mg. Cefuroxime was bactericidal against the isolates with exquisite or slightly diminished susceptibility to penicillin (−4 and −3.9 log10 cfu/ml killing, respectively) during the 6 h incubation period. In contrast, there was only a 2.8 log10 cfu/ml reduction in the initial inoculum of six of the eight isolates resistant to penicillin (MIC 2 mg/l). The two remaining penicillin-resistant isolates (cefuroxime MIC 8 mg/l) only showed a 2 log10 cfu reduction in the initial inoculum. [ABSTRACT FROM AUTHOR]