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M/emm typing, based either on serotyping of the M protein or on sequencing of the emm gene, is a major tool for epidemiological studies of group A streptococci (GAS). In order to simplify M/emm typing, we designed two multiplex polymerase chain reaction (PCR) formats capable of identifying the most frequent GAS M/emm types involved in invasive infections and antimicrobial resistance. A heptaplex PCR procedure was first developed in a conventional format coupled with gel electrophoresis to identify emm types 1, 3, 4, 6, 12, 28, and 89, based on the size of the amplification products. The other method, designed to identify the same seven emm types, together with emm11, was based on a real-time PCR format coupled with high-resolution melting (HRM) analysis, allowing the rapid typing of large strain collections.

Activities of combinations of beta-lactams, daptomycin, gentamicin, teicoplanin, and vancomycin against 11 clinical isolates of Enterococcus faecium highly resistant to glycopeptides, three plasmid-cured derivatives, eight E. faecalis and E. faecium transconjugants, and two susceptible recipient strains were tested. A marked synergy between penicillins or imipenem and glycopeptides against the glycopeptide-resistant strains but not against the glycopeptide-susceptible strains was observed by the double-disk agar diffusion assay. The synergy of combinations of amoxicillin, imipenem, penicillin G, or piperacillin with vancomycin or teicoplanin against resistant strains was confirmed by the checkerboard technique. The fractional inhibitory concentration indexes were generally below 0.25, except for one strain of E. faecium resistant to high levels of penicillin G. However, the combinations were not bactericidal as tested by time-killing experiments, and high concentrations (64 micrograms/ml) of amoxicillin, penicillin G, or piperacillin combined with 8 micrograms of vancomycin or teicoplanin per ml tended to be antagonistic. Addition of 4 micrograms of gentamicin per ml to these combinations enhanced their bactericidal effect, but they occasionally remained slightly less effective than beta-lactams associated with gentamicin. The combination of 10 micrograms of daptomycin per ml with gentamicin was bactericidal after 6 h against 11 glycopeptide-resistant strains.

Daptomycin, vancomycin, ampicillin and aminoglycosides, alone or in combination, were tested for their bactericidal activity against 15 isolates of vancomycin-resistant Enterococcus faecium from immunocompromised children. The kill-kinetic studies at clinically achievable concentrations demonstrated that daptomycin alone or in combination with ampicillin had the greatest bactericidal activity.

We aimed to assess the independent effect of clinical spectrum, bacterial inoculum size and physician characteristics on the sensitivity of a rapid antigen detection test (RADT) for group A streptococcus (GAS) in children. Double throat swabs were collected from 1,482 children with pharyngitis and 294 asymptomatic children in a French prospective, office-based, multicenter ( n = 17) study, from October 2009 to May 2011. Patient- and physician-level factors potentially affecting RADT sensitivity were studied by univariate and multivariate multilevel analysis, with laboratory throat culture as the reference test. In children with pharyngitis and asymptomatic children, the prevalence of GAS was 38 % (95 % confidence interval 36-41 %) and 11 % (7-14 %), respectively. Overall, RADT sensitivity was 87 % (84-90 %). On stratified and multivariate multilevel analysis, RADT sensitivity was higher for children with pharyngitis than asymptomatic children (89 % vs. 41 %), children <9 than ≥9 years old (88 % vs. 79 %) and those with heavy than light inoculum (94 % vs. 53 %). RADT sensitivity was influenced by the physician performing the test (range 56-96 %, p = 0.01) and was higher for physicians with hospital-based clinical activity in addition to office-based practice (adjusted odds ratio 3.4 [95 % confidence interval 1.9-6.3], p < 0.001); inter-physician variations in RADT sensitivity were largely explained by this variable (proportional change in variance >99 %). The sensitivity of the RADT is independently affected by patient- and physician-level factors. Physicians who base their diagnosis of GAS pharyngitis on the results of a RADT alone should consider diagnostic accuracy monitoring and adequate training when needed. [ABSTRACT FROM AUTHOR]

Cefprozil is a new oral cephalosporin with activity against the most common pathogens isolated in acute otitis media. This randomized study enrolled 361 patients (mean age 29 months). Physical examination and culture via tympanocentesis were required less than 48 h before therapy. One hundred and ninety-one patients were evaluable for clinical efficacy; 99 received cefprozil (20 mg/kg/day bd) and 92 received amoxycillin/clavulanate (13.3 mg/kg/day tid). Duration of treatment was 7-9 days for 81 patients, 10 days for 105 patients and 11-16 days for five patients. The treatment groups were comparable with respect to demographics, severity of infection and number of previous episodes. Clinical evaluations of efficacy were based on physical examination including otoscopy within a 14 day period after therapy. Satisfactory clinical responses were achieved in 84% of cefprozil-treated patients and 87% of amoxycillin/clavulanate-treated patients. Pathogens most commonly isolated included Haemophilus influenzae (33%) and Streptococcus pneumoniae (22%). All 361 patients were evaluable for safety. Adverse clinical events were reported in 13% (24) of cefprozil-treated patients and 20% (36) of amoxycillin/clavulanate-treated patients. Cefprozil, administered twice a day, is comparable to a regimen of amoxycillin/clavulanate three times a day in the treatment of acute otitis media in children. [ABSTRACT FROM AUTHOR]

Restriction fragment length polymorphism (RFLP) analysis of total DNA and of ribosomal DNA (rDNA) regions (ribotyping) were used to document Streptococcus pyogenes vertical mother-to-infant transmission and to investigate the spread of S. pyogenes in an obstetric unit. Two isolates from a newborn, two isolates from his mother (patient 1), and two isolates from two other mothers (patients 2 and 3) were studied. RFLP of total DNA, both after HindIII and PvuII digestions and ethidium bromide staining, gave indistinguishable patterns for the strains isolated from the neonate, his mother, and patient 2. Strains from patient 3 and six unrelated strains studied for comparison showed different patterns. In our system, ribotyping was less discriminative than total DNA RFLP analysis. DNA RFLP analysis therefore provides a valuable molecular tool for studying S. pyogenes epidemiology. [ABSTRACT FROM AUTHOR]

Abstract: Streptococcus pneumoniae (Sp) is an important cause of morbidity and mortality among paediatric infectious diseases. The aim of this study is to analyse specifical data on Sp meningitis out of the Bacterial Meningitis (BM) French Surveillance Network about mean age of BM cases and clinical features. Overall 367 Sp BM were reported between January 2001 to January 2004 (sex ratio M/F: 1.3), 69.7% were&#60;2 years old, median age 0.8 year (minmax 0–16.8 years). Before two years old children, 94.1% had no medical risk factor and no underlying conditions: on the other hand, after two years old, these factors were reported in 27% cases (P &#60;0.001). Mortality rate was 10.9%. On account of a Sp BM''s pic at five months, data of the BM French Surveillance Network confirm the necessity of an early vaccination. The vaccine administration at two, three, four months with a booster during the second year, recommended in the vaccinal french calendar, seems particularly adapted to the Sp BM in France. [Copyright &y& Elsevier]

Abstract: Since the 1980s, infections due to Streptococcus pyogenes or group A streptococci (GAS) were marked by the increase in invasive infections and the emergence of clones which were resistant to macrolides. Those challenges led the French national reference center for streptococci to enhance the epidemiological survey and the characterization of GAS strains, in collaboration with the National Institute for Public Health Surveillance. Active surveillance is of major importance for implementation of therapeutic and prophylactic guidelines and for evaluation of future streptococcal vaccines. [Copyright &y& Elsevier]

L’antibiothérapie empirique de l’angine à Streptococcus pyogenes (SGA) repose sur des études épidémiologiques de la résistance aux antibiotiques. Le but de notre étude a été d’évaluer l’activité de différents antibiotiques (pénicilline G, amoxicilline, érythromycine, clarithromycine et clindamycine) vis-à-vis de 206 souches de SGA isolées d’angines aiguës de l’enfant entre 2002 et 2004. Les CMI 50 et 90 de l’érythromycine, la clarythromycine et la clindamycine ont été déterminées sur les 100 premières souches par la méthode de dilution en milieu gélosé (CA-SFM). Les gènes de résistance aux macrolides (ermA, ermB, mef) ont été recherchés par PCR sur les souches résistantes aux macrolides.Aucune résistance vis-à-vis des ß-lactamines n’a été observée. En revanche, notre étude met en évidence l’émergence de la résistance aux macrolides chez SGA avec une prévalence de la résistance à l’érythromycine et à la clarythromycine de 14,5 % et de 12,6 % à la clindamycine. Les gènes ermB et mefA ont été retrouvés chez respectivement 13,5 et 1 % des souches, leur conférant ainsi le phénotype MLSB ou M. [Copyright &y& Elsevier]

Dans le cadre de ses missions de contrôle des produits de santé, l''Afssaps en collaboration avec deux autres sites experts, a réalisé une évaluation des 16 tests de diagnostic rapide (TDR) des angines à Streptocoque A présents sur le marché français en 2002. Cette étude a été réalisée dans un but de surveillance du marché afin de s''assurer du caractère fiable et rapide de ces TDR et a eu pour objectif de préciser certaines caractéristiques analytiques et pratiques de ces réactifs. L''étude analytique a été réalisée sur un même panel de dilutions de quatre souches de référence de Streptococcus pyogenes afin de déterminer dans les mêmes conditions méthodologiques le seuil de détection de tous les réactifs. Les seuils de détection ont été calculés à partir des résultats exprimés en unités formant colonie par ml (UFC/ml). L''étude de praticabilité a permis d''analyser la qualité de leur présentation, la facilité de lecture et de réalisation des tests. Un score a été établi pour chacun des réactifs. Une classification de ces 16 dispositifs en termes de sensibilité analytique (seuil de détection) et praticabilité (score) a été réalisée. En ce qui concerne la sensibilité analytique, les réactifs les plus performants sont ceux qui présentent les seuils permettant de détecter la plus faible concentration bactérienne à savoir 105 UFC/ml. En terme de praticabilité, il apparaît que les techniques immunochromatographiques sur bandelettes sont les mieux classées dans une utilisation en dehors d''un laboratoire d''analyses de biologie médicale. [Copyright &y& Elsevier]