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Blistering distal dactylitis is a distinct clinical entity, generally due to S. pyogenes, unfrequently reported. Characteristically, blistering distal dactylitis is described as a localized infection involving the distal phalanx of the digits, and it usually presents as a fluid-filled blister. Between October 2009 and June 2014, 69 children (median age: 60 months, extremes: 0,6-176) were enrolled. The sensitivity of GAS rapid antigen detection test was 97 % (CI 95 %: 83-100 %), the specificity was 76 % (CI 95 %: 60-89 %), the negative predictive value was 97 % (CI 95 %: 83-100 %), and the positive predictive value 76 % (CI 95 %: 60-89 %). All patients with a positive GAS rapid antigen test were treated with antibiotics (amoxicillin essentially) and cured without surgery.

The group A streptococcus (GAS) is the 5(th) responsible pathogen of invasive infections in children in France. These particularly severe diseases are dominated in children by soft tissue infection, isolated bacteremia but also osteoarthritis. Other complications are rare in France such as lung infections, necrotizing fasciitis (NF) and streptococcal toxic shock syndrome (STSS). More unusual localizations such as meningitis, neonatal infections, severe ear and throat and gastrointestinal infections and vascular disorders are also described. Based on published series, mortality ranging from 0-8 % of cases, is high but still lower than that observed in adults. Probabilistic antibiotherapy includes a β-lactam with anti-SGA but also anti-staphylococcal (predominantly methi-S in France) activity such as clavulanic acid- amoxicillin followed by amoxicillin as soon as identification of SGA is performed. The addition of an anti-toxin antibiotic such as clindamycin is recommended particularly in NF or STSS or clinical signs suggestive of toxin production by the SGA (rash, gastrointestinal signs, hemodynamic disorders). The use of intravenous polyvalent immunoglobulins must also be discussed in NF and STSS. In all cases surgery should be discussed. The prognosis of these potentially very severe infections is related to their early diagnosis and treatment. A better understanding of the pathophysiology of these infections may optimize their management but also their prevention.

Resume Dans les pays industrialises, les infections a streptocoque du groupe A etaient auparavant une source d’inquietude du fait de la survenue de rhumatismes articulaires aigus et de leurs complications cardiaques. Cette entite qui tend a disparaitre actuellement dans ces pays laisse la place a des infections invasives streptococcique de haute morbidite et mortalite, en particulier les fasciites necrosantes, le plus souvent en association avec la varicelle. L’introduction du vaccin contre la varicelle, dans le calendrier regulier vaccinal quebecois, s’est accompagnee d’une diminution signifi cative de la frequence des cas de fasciites necrosantes ou de cellulite. Cependant, nous n’avons pas pu mettre en evidence une diminution de la frequence des infections invasives a streptocoque du groupe A, en raison d’une augmentation du nombre d’infections pleuro-pulmonaires et osteo-articulaires.

The pathogenicity of s-hemolytic group A streptococcus (GAS) is particularly diverse, ranging from mild infections, such as pharyngitis or impetigo, to potentially debilitating poststreptococcal diseases, and up to severe invasive infections such as necrotizing fasciitis or the dreaded streptococcal toxic shock syndrome. This variety of clinical expressions, often radically different in individuals infected with the same strain, results from a complex interaction between the bacterial virulence factors, the mode of infection and the immune system of the host. Advances in comparative genomics have led to a better understanding of how, following this confrontation, GAS adapts to the immune system's pressure, either peacefully by reducing the expression of certain virulence factors to achieve an asymptomatic carriage, or on the contrary, by overexpressing them disproportionately, resulting in the most severe forms of invasive infection.

Resume Le streptocoque du groupe A (SGA) est un germe humain responsable d’un large eventail de manifestations cliniques. Les infections invasives a SGA sont en recrudescence depuis le milieu des annees 1980. Afin d’etudier l’epidemiologie des infections invasives a SGA en France, nous avons caracterise toutes les souches invasives recues au Centre national de reference des streptocoques (CNR-Strep) entre 2007 et 2011 et analyse les questionnaires de renseignements cliniques accompagnant les souches. Pour chaque souche ont ete determines le genotype emm , les genes de superantigenes et la sensibilite aux antibiotiques. Sur les 2 603 souches invasives non redondantes de SGA etudiees, 65,1 % ( n = 1 695) provenaient d’hemoculture. Un syndrome de choc toxique streptococcique (SCTS) etait decrit dans 16,4 % ( n = 428) des cas, notamment en cas de dermohypodermite necrosante (DHN), d’infections pleuropulmonaires ou osteo-articulaires ( p ≤ 0,001). Le taux de mortalite s’elevait a 10,6 %. Au total, 102 genotypes emm differents ont ete identifies. Trois genotypes predominaient, atteignant pres de 60 % des souches : emm 1 (26,7 %), emm 28 (16,4 %), et emm 89 (12,8 %). La preponderance de chaque genotype emm etait variable selon les annees et l’âge des patients. Chez les emm 1 (36,8 %), emm 12 (12,9 %) et emm 4 (9,5 %). La distribution des genes de superantigenes ( Spe A, Spe C et Ssa ) etait restreinte a certains genotypes emm . Entre 2007 et 2011, le taux de resistance aux macrolides des SGA a diminue de 7,8 a 5,5 %. Les souches emm 1 restent les plus repandues, en particulier lors des manifestations cliniques les plus severes (SCTS, DHN).

Group A streptococcus (GAS) is the most frequently identified bacterium in children with acute pharyngitis. Clinical signs and symptoms cannot distinguish accurately between viral and GAS pharyngitis. Rapid antigen detection tests (RADTs) can identify GAS by an immunologic reaction within a few minutes. Compared to throat culture, most RADTs have a high specificity (around 95 %), allowing antibiotic prescribing on the basis of a positive RADT result. Similarly, the negative predictive value of RADTs seems sufficiently high (around 95 %) to ensure against the presence of GAS in case of a negative RADT result. Among several factors affecting RADT sensitivity, the training and expertise of the person performing the test and the quality of the throat swab specimen seem to be key determinants. Available evidence suggests that clinical prediction rules for the triage of children who should undergo GAS testing are not sufficiently accurate. Implementing RADTs into clinical practice has an important impact on antibiotic prescription rates, for a reduction of about 30 %. French guidelines that recommend using RADTs in all children above 3 years of age presenting with pharyngitis without backup culture of negative tests seem relevant in this context.

Perineal diseases in children are usually caused by group A streptococcus (GAS). If the natural course of untreated cases is not known, it is well known that symptoms do not resolve spontaneously and can persist often for many months, until appropriate diagnosis and effective treatment are instituted. Furthermore, failures and recurrences after penicillin treatment are frequent. From 2009 to 2014, 165 perineal infections (median age: 48 months, extremes: 0.4-139) were enrolled by 15 pediatricians: 4 balanitis, 29 vulvo-vaginal diseases and 132 perianal infections. Painful defecation, anal fissures and macroscopic blood in stools were significantly more frequent in GAS perianal infections than negative GAS infections (p

Extraintestinal pathogenic Escherichia coli (ExPEC) causing urinary tract infections, bacteraemia or meningitis are characterized by a particular genetic background (phylogenetic group B2 and D) and the presence, within genetic pathogenicity islands (PAI) or plasmids, of genes encoding virulence factors involved in adhesion to epithelia, crossing of the body barriers (digestive, kidney, bloodbrain), iron uptake and resistance to the immune system. Among the many virulence factors described, two are particularly linked with a pathophysiological process: type P pili PapGII adhesin is linked with acute pyelonephritis, in the absence of abnormal flow of urine, and the K1 capsule is linked with neonatal meningitis. However, if the adhesin PapGII appears as the key factor of pyelonephritis, such that its absence in strain causing the infection is predictive of malformation or a vesico-ureteral reflux, the meningeal virulence of E. coli can not be reduced to a single virulence factor, but results from a combination of factors unique to each clone, and an imbalance between the immune defenses of the host and bacterial virulence.

Group A streptococcal (GAS) meningitis in children are rare. The aim of this study was to analyze the clinical, biological and outcome data on GAS meningitis recorded in the Bacterial Meningitis (BM) French Surveillance Network (GPIP/ACTIV). From 2001 through 2012, 4,564 children suffering from proven bacterial meningitis were recorded in the data base. Among them, 0.7 % were GAS infections. The median age was 5.6 years. A history of community acquired infection before the onset of GAS meningitis was frequent. Apart from the identification of the bacterial species, GAS meningitis were clinically and biologically indistinguishable from meningitis caused by other pathogens notably S. pneumoniae. Case fatality rate was 8 %.

The purpose of this study was to assess the performances of the group A streptococcus (GAS) rapid antigen diagnostic tests (RADTs) in extra-pharyngeal infections. Between October 2009 and June 2014, 368 patients (median age: 48 months) were enrolled. The pathologies involved were : 160 perineal infections (44 %), 69 blistering distal dactylitis (19 %), 55 cervical lymphadenitis (15 %), 31 crusty or bleeding rhinitis (8 %), and 53 other diseases (14 %). The sensitivity of GAS-RADT used was 96 % (95 % CI: 92-99 %), the specificity 81 % (95 % CI: 75- 86 %), the negative predictive value 97 % (CI 95 %: 93-99 %), and the positive predictive value 79 % (95 % CI: 73-85 %). Finally, positive and negative likelihood ratio were 5 (95 % CI: 4-7) and 0.05 (95 % CI: 0.02-0.11) respectively. The GAS-RADTs developed for pharyngitis have comparable performances in these settings and therefore can be used.

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.

Resume Objectif Analyse descriptive des caracteristiques cliniques, biologiques et pronostiques des meningites a Escherichia coli chez l’enfant. Methodes Les donnees cliniques et biologiques des enfants ayant presente une meningite neonatale a E. coli (MNEC) de 1988 a 2004 ont ete collectees retrospectivement et ont ete confrontees aux caracteristiques phenotypiques et genotypiques des souches. L’approche moleculaire des souches a consiste en une analyse du groupe phylogenetique, du sequence-O-type, de l’empreinte genetique de virulence. La virulence des souches responsables de deces a ete testee dans un modele animal de meningite du rat nouveau-ne. Resultats Quatre-vingt dix-neuf dossiers ont ete inclus. L’âge median des enfants etait de 10 jours (0 a 90 jours) et 83 patients etaient des nouveau-nes. Trente-trois enfants etaient des prematures. L’hyper ou l’hypothermie etait le signe clinique le plus frequemment present a l’admission. 28 % des enfants de plus de 6 jours presentaient une infection urinaire associee. La cytologie du LCR etait anormale dans 97 % des cas. Douze heures apres l’admission 34 % des enfants ont necessite une prise en charge en reanimation. Un tiers des echographies trans-fontanellaires realisees a l’admission etaient anormales. La sterilisation du LCR a ete retardee pour 15 % des enfants, malgre une antibiotherapie adaptee. L’adjonction de la ciprofloxacine a ete associee a une meilleure sterilisation du LCR (94 % vs 77 %, p = 0,03). 6 enfants ont presente une recidive. Le suivi en moyenne a ete de huit mois avec 21 % de sequelles observees. Le taux de mortalite des MNEC a ete de 14 %. La mortalite etait associee aux signes de choc septique (57 % vs 3 %, p Conclusion La mortalite des meningites a E. coli reste elevee. L’utilisation d’une approche clinique et moleculaire des souches a permis d’etablir une relation entre les souches appartenant a des sequences-O-types peu frequents et la mortalite. Ces souches qui sont avirulentes dans le modele animal suggerent que le deces pourrait etre lie d’avantage a la susceptibilite de l’hote qu’a la virulence des souches.

Objectifs Realiser une validation externe des regles de decision clinique (RDC) pour le diagnostic des angines a streptocoque du groupe A (SGA). Sujet / materiels et methodes Les 8 RDC identifiees grâce a une revue systematique ont ete appliquees aux donnees d’une cohorte prospective de 676 enfants avec angine de la maniere suivante : faible risque de SGA d’apres la RDC, pas de test de diagnostic rapide (TDR) ni d’antibiotique ; risque intermediaire, antibiotherapie selon le resultat d’un TDR ; haut risque, antibiotherapie empirique. Le test de reference etait la culture de prelevement de gorge. Les donnees manquantes ont ete gerees par imputation multiple. Resultats principaux La calibration des RDC etait faible et aucune RDC n’etait capable de rejeter ou de confirmer le diagnostic de SGA (risque de SGA rho =0,94 ; p Conclusions Les RDC disponibles pour selectionner les enfants chez qui realiser un TDR ne sont pas suffisamment bien calibrees ni performantes pour pouvoir etre recommandees en pratique clinique.