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Staphylococcus aureus is one of the main pathogens isolated from diabetic foot infections (DFI). The purpose of this study was to evaluate the importance of the persistence of S. aureus in this environment and the possible modifications of the bacterial genome content over time. Molecular typing of S. aureus isolates cultured from patients with the same DFI over a 7-year study revealed a 25% rate of persistence of this species in 48 patients, with a short median persistence time of 12weeks (range: 4–52weeks). Non-specific clonal complexes were linked to this persistence. During the follow-up, bla genes were acquired in three cases, whereas some virulence markers were lost in all cases after a long period of colonization (21.5weeks). Only one patient (2%) had a long-term persistence of 48weeks. The genome sequencing of a clonal pair of early/late strains isolated in this patient showed mutations in genes encoding bacterial defence and two-component signal transduction systems. Although, this study suggests that the long-term persistence of S. aureus in DFI is a rare event, genomic evolution is observed, highlighting the low adaptive ability of S. aureus to the specific environment and stressful conditions of diabetic foot ulcers. These results provide the basis for better understanding of S. aureus dynamics during persistent colonization in chronic wounds.

International audience; The emergence of carbapenemase-producing Gram-negative bacilli is a worldwide problem. To date, no study has evaluated the prevalence of faecal carriage of carbapenemase-producing and carbapenem-resistant Gram-negative bacilli (CR GNB) in France. From 1 February to 30 April 2012, we conducted a prospective, multicentre study in three University Hospitals and four General Hospitals in the south of France. The carriage of carbapenemase-producing Enterobacteriaceae (CPE) and other CR GNB was screened by both cultivation on chromID® CARBA and chromID® OXA-48 media (bioMérieux) and molecular tools [multiplex polymerase chain reaction (PCR) and NucliSENS EasyQ® KPC (bioMérieux)]. The genetic relationship between isolates was assessed by rep-PCR (DiversiLab, bioMérieux) or multilocus sequence typing (MLST). The prevalences of CR GNB and carbapenemase-producing bacteria were 2.4 % (27/1,135) and 0.4 % (n = 5), respectively. Two strains corresponded to OXA-23-producing Acinetobacter baumannii and belonged to the widespread sequence type (ST) 2/international clone II, whereas one strain was an ST15 OXA-48-producing Klebsiella pneumoniae. Two OXA-48-producers were detected exclusively by PCR. This first French study revealed the very low dissemination of carbapenemase-producing bacteria in patients attending hospitals in southern France during a non-outbreak situation. However, the increasing description of epidemic cases in this area must reinforce the use of hygiene procedures to prevent diffusion of these multidrug-resistant microorganisms.

The aim of this study was to determine the presence of oxyiminocephalosporin-resistant (OCR) Gram-negative bacilli and extended-spectrum β-lactamase (ESBL)-producing isolates in stool specimens obtained from paediatric patients hospitalised for acute diarrhoea. We conducted a prospective, multicentre study over a period of 6 months in seven hospitals in the south of France. Samplings were carried out from infants admitted for acute diarrhoea with no previous antibiotic treatment in the last week. Bacteria in stool specimens were screened for the presence of OCR Gram-negative bacilli on Drigalski agar supplemented with ceftazidime and ESBL CHROMagar® media, and confirmed by the Rosco tablets test. Genetic detection was performed by the Check MDR® microarray and by polymerase chain reaction (PCR) and sequencing with bacterial DNA extracted from isolates. The presence of OCR enterobacteria was markedly high (177/1,118 patients, 15.2 %), with an important community origin (66.1 %). The majority of multidrug-resistant (MDR) bacteria were Enterobacter cloacae (106, 59.9 %) and Escherichia coli (61, 34.5 %). The prevalence of ESBL and CTX-M producers represented 5.2 and 4.3 % of the isolates, respectively. The main proportion of these ESBL carriers was found in children less than 1 year of age (53.4 %). One carbapenemase (IMP-1) was detected. The study revealed the wide dissemination of MDR bacteria in infants attending hospitals in the south of France during a non-outbreak situation, in particular, the spread of cefotaximase and the detection of a carbapenemase. This worrisome situation must reinforce the use of hygiene procedures and appropriate antibiotics to control the emergence and spread of OCR organisms.

The aim of this study was to describe the epidemiology of enterococci isolated from infections at an Algerian university hospital, and to evaluate the prevalence of vancomycin-resistant enterococci (VRE) and the clonal cluster present in this country.Patients who presented at Annaba University Hospital with Enterococcus infections were prospectively included over a 1-y period (2010). All Enterococcus sp. isolated were characterized by antibiotic resistance, van and erm genes, repetitive sequence-based polymerase chain reaction (rep-PCR), multi-locus sequence typing (MLST), and virulence genes.A total of 125 Enterococcus isolates recovered from 125 patients (59% female; median age 54 y, range 2-86 y) were studied. No differences in epidemiological data were observed between infections by Enterococcus faecalis vs Enterococcus faecium. However a high proportion of E. faecium were resistant to ampicillin (95%). The prevalence of VRE, corresponding to 4 vanC1-Enterococcus gallinarum, was 3.2%. A high level of genomic diversity among strains was noted, with the importance of sequence type (ST) 78 (which belongs to clonal complex (CC) 17) in E. faecium and ST317 and CC2 in E. faecalis.This first study on enterococci isolated in Algeria shows the low prevalence of VRE, but the presence of clonal complexes linked to VRE and vancomycin-sensitive enterococci associated with hospital infections. Moreover the high level of macrolide resistance and/or ampicillin resistance in E. faecium suggests close monitoring of the epidemiology of these strains.

We compared the virulence properties of a collection of asymptomatic bacteriuria (ABU) Escherichia coli strains to urinary tract infection (UTI) strains isolated from pregnant women in a university hospital over 1 year. The in vitro and in vivo studies suggest that ABU strains presented a virulence behavior similar to that of strains isolated from cases of cystitis.