Antibiotic resistance and plasmid transfer capacity in biofilm formed with a CTX-M-15-producing Klebsiella pneumoniae isolate.

International audienceTo characterize a CTX-M-15-producing Klebsiella pneumoniae isolate that was identified during an outbreak involving 16 patients who had undergone endoscopic retrograde cholangiopancreatography between December 2008 and August 2009. The strain was also detected in one endoscope used for these examinations. Disc diffusion assays, MICs and isoelectric focusing were used to characterize the plasmidic CTX-M-15 β-lactamase. PCRs were used to check for the presence of genes associated with virulence or antibiotic resistance. Antibiotic tolerance tests and plasmid transfer were carried out in both planktonic and biofilm conditions. The strain belonged to sequence type 14 and to the virulent capsular serotype K2, but produced little glucuronic acid. It contained a 62.5 kb conjugative plasmid carrying the bla(CTX-M-15), bla(OXA-1) and aac(6')-Ib-cr genes and harboured few virulence genes (uge, wabG, kfu and mrkD). The strain was highly resistant to cefotaxime (MIC 516 mg/L) and the presence of this antibiotic at sub-MIC concentrations enhanced biofilm formation. The isolate was susceptible to ofloxacin (MIC 2 mg/L), but the bactericidal effect of this antibiotic was greater in planktonic cultures and 6 h old biofilm than in 24 or 48 h old biofilms. The K. pneumoniae strain was notable for its ability to transfer its plasmid, especially in biofilm conditions, in which the rate of plasmid transfer was about 0.5/donor. These findings demonstrate the ability of this strain to survive in a hospital environment and to transfer its extended-spectrum β-lactamase-encoding plasmid

Assessment on experimental bacterial biofilms and in clinical practice of the efficacy of sampling solutions for microbiological testing of endoscopes

International audienceOpinions differ on the value of microbiological testing of endoscopes, which varies according to the technique used. We compared the efficacy on bacterial biofilms of sampling solutions used for the surveillance of the contamination of endoscope channels. To compare efficacy, we used an experimental model of a 48-h Pseudomonas biofilm grown on endoscope internal tubing. Sampling of this experimental biofilm was performed with a Tween 80-lecithin-based solution, saline, and sterile water. We also performed a randomized prospective study during routine clinical practice in our hospital sampling randomly with two different solutions the endoscopes after reprocessing. Biofilm recovery expressed as a logarithmic ratio of bacteria recovered on bacteria initially present in biofilm was significantly more effective with the Tween 80-lecithin-based solution than with saline solution (P = 0.002) and sterile water (P = 0.002). There was no significant difference between saline and sterile water. In the randomized clinical study, the rates of endoscopes that were contaminated with the Tween 80-lecithin-based sampling solution and the saline were 8/25 and 1/25, respectively (P = 0.02), and the mean numbers of bacteria recovered were 281 and 19 CFU/100 ml (P = 0.001), respectively. In conclusion, the efficiency and therefore the value of the monitoring of endoscope reprocessing by microbiological cultures is dependent on the sampling solutions used. A sampling solution with a tensioactive action is more efficient than saline in detecting biofilm contamination of endoscopes

<i>Pseudomonas aeruginosa</i> intensive care unit outbreak:winnowing of transmissions with molecular and genomic typing

Bioinformatics and computational biology analyses were supported by the University of St Andrews Bioinformatics Unit which is funded by a Wellcome Trust ISSF award [grant 097831/Z/11/Z]. BJP, KO, MP, MTGH, GP and SHG are funded by the Chief Scientist Office through the Scottish Infection Research Network, a part of the SHAIPI consortium grant reference number SIRN/10.Background: Pseudomonas aeruginosa healthcare outbreaks can be time consuming and difficult to investigate. Guidance does not specify which typing technique is most practical to base decisions on. Aim: We explore the usefulness of whole genome sequencing (WGS) in the investigation of a Pseudomonas aeruginosa outbreak describing how it compares with pulsed-field gel electrophoresis (PFGE) and variable number tandem repeat (VNTR) analysis. Methods: Six patient isolates and six environmental samples from an Intensive Care Unit (ICU) positive for P. aeruginosa over two years underwent VNTR, PFGE and WGS. Findings:  VNTR and PFGE were required to fully determine the potential source of infection and rule out others. WGS results unambiguously distinguished linked isolates giving greater assurance of the transmission route between wash hand basin (WHB) water and two patients supporting control measures employed. Conclusion:  WGS provided detailed information without need for further typing. When allied to epidemiological information it can be used to understand outbreak situations rapidly and with certainty. Implementation of WGS in real-time would be a major advance in day-to-day practice. It could become a standard of care as it becomes more widespread due to its reproducibility and reduction in costs.Publisher PDFPeer reviewe

Gyrospun antimicrobial nanoparticle loaded fibrous polymeric filters

© 2016 The Authors. Published by Elsevier B.V. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).A one step approach to prepare hybrid nanoparticle embedded polymer fibres using pressurised gyration is presented. Two types of novel antimicrobial nanoparticles and poly (methylmethacrylate) polymer were used in this work. X-ray diffraction analysis of the nanoparticles revealed Ag, Cu and W are the main elements present in them. The concentration of the polymer solution and the nanoparticle concentration had a significant influence on the fibre diameter, pore size and morphology. Fibres with a diameter in the range of 6-20 ìm were spun using 20 wt% polymer solutions containing 0.1, 0.25 and 0.5 w% nanoparticles under 0.3 MPa working pressure and a rotational speed of 36000 rpm. Continuous, bead-free fibre morphologies were obtained for each case. The pore size in the fibres varied between 36-300 nm. Successful incorporation of the nanoparticles in polymer fibres was confirmed by energy dispersive x-ray analysis. The fibres were also gyrospun on to metallic disks to prepare filters which were tested for their antibacterial activity on a suspension of Pseudomonas aeruginosa. Nanoparticle loaded fibres showed higher antibacterial efficacy than pure poly(methylmethacrylate) fibres.8pÍuPeer reviewedFinal Published versio

Two cases of monomicrobial intraabdominal abscesses due to KPC - 3 Klebsiella pneumoniae ST258 clone

<p>Abstract</p> <p>Background</p> <p>Knowledge of the etiology of pyogenic liver and pancreatic abscesses is an important factor in determining the success of combined surgical and antibiotic treatment. Literature shows geographical variations in the prevalence and distribution of causative organisms, and the spread of <it>Klebsiella pneumoniae </it>carbapenemase-producing bacteria is an emerging cause of abdominal infections.</p> <p>Case presentation</p> <p>We herein describe two cases of intra-abdominal abscesses due to monomicrobial infection by <it>Klebsiella pneumoniae </it>Sequence Type 258 producing <it>K. pneumoniae </it>carbapenemase 3 (KPC-Kp). In case 1, a 50-year-old HIV-negative Italian woman with chronic pancreatitis showed infection of a pancreatic pseudocystic lesion caused by KPC-Kp. In case 2, a 64-year-old HIV- negative Italian woman with pancreatic neoplasm and liver metastases developed a liver abscess due to KPC after surgery. Both women were admitted to our hospital but to different surgical units. The clonal relationship between the two isolates was investigated by pulsed-field gel electrophoresis (PFGE). In case 2, the patient was already colonized at admission and inter-hospital transmission of the pathogen was presumed. A long-term combination regimen of colistin with tigecycline and percutaneous drainage resulted in full recovery and clearance of the multidrug-resistant (MDR) pathogen.</p> <p>Conclusions</p> <p>Timely microbiological diagnosis, the combined use of new and old antibiotics and radiological intervention appeared to be valuable in managing these serious conditions. The emergence and dissemination of MDR organisms is posing an increasing challenge for physicians to develop new therapeutic strategies and control and prevention frameworks.</p

The social protection of an employed athlete

Par son activité salariée, le sportif est intégré au système interprofessionnel de sécurité sociale. Les particularismes de l’activité sportive, tenant à la nature et à l’organisation de celle-ci, rendent néanmoins cette intégration complexe et difficile. La pluriactivité du sportif, mais également l’intervention massive des fédérations sportives, syndicats, partenaires et organisateurs de compétitions, doivent être prises en compte par le cadre normatif applicable. Il en est de même de l’importance des risques professionnels affectant le sportif et de la brièveté de sa carrière. Le système national, uniforme et public de protection sociale est alors confronté à ses limites. Tandis que la réparation des risques sociaux est insuffisante, la prévention et l’accompagnement socioprofessionnel du sportif salarié sont presque inexistants. La cadre légal applicable ne peut pleinement satisfaire. Face à ces carences, il appartient à la convention collective d’assurer une sécurité sociale professionnelle de la personne. Une protection sociale complémentaire et supplétive adaptée à l’activité sportive salariée se construit. Elle permet à la fois d’épouser les contours de la sécurité sociale et d’intégrer les dispositifs individuels et collectifs développés par les différents acteurs de l’activité sportive. La sécurisation effective de la personne est alors assurée par un cumul des formes de protection. Il s’agit ainsi de proposer une protection sociale organisée en différents niveaux s’adaptant à la réalité de l’activité professionnelle développée.Owing to the employed activity he pursues, a paid athlete is part of the interprofessional social protection system. Sporting activities have certain specificities, due to their nature and organisation, which make their inclusion into the system more complicated and difficult. The multiple activities the athlete may carry on, as well as the significant intervention of sporting federations, trade unions, partners and organisers of sporting events, must be taken into account by the applicable normative framework. The same applies to the extent of the occupational hazards which affect the athlete and to the brievity of his career. The standardised and public national social protection system is then faced with its own limits. While the compensation of social risks is inadequate, there are hardly any prevention and socio-occupational assistance. The applicable legal framework cannot therefore be fully satisfactory. To tackle these deficiencies, collective labour agreement must ensure an occupational social protection for the individual. An additional and auxiliary social protection adapted to the status of an employed sporting activity then starts to build up. It allows both to match the outline of the national social security and to integrate the individual and collective packages designed by the stakeholders of the sporting activity field. The actual safety of the individual is then guaranteed through the combination of these different forms of social protection. The point is thus to offer a social protection organised in different layers suitable for the developed sporting activity

Un suivi médical plus efficient ?

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