National survey of colistin resistance among carbapenemase-producing Enterobacteriaceae and outbreak caused by colistin-resistant OXA-48-producing Klebsiella pneumoniae, France, 2014

From January 2014 to December 2014, 972 consecutive non-replicate carbapenemase-producing Enterobacteriaceae isolates from colonised or infected patients were collected at the Associated French National Reference Centre as part of the French national survey on antimicrobial resistance. It included 577 Klebsiella spp. (59%), 236 Escherichia coli (24%), 108 Enterobacter spp. (11%), 50 Citrobacter spp. (5%), and a single Salmonella spp. isolate (0.1%). Of 561 K. pneumoniae isolates, 35 were found to be resistant to colistin (6.2%). PFGE analysis revealed a clonal outbreak involving 15 K. pneumoniae isolates belonging to sequence type ST11, recovered in a single hospital in the Picardie region in northern France. Those clonally related isolates showed variable levels of resistance to colistin, ranging from 4 to 64 mg/L. They harboured the blaOXA-48 carbapenemase gene and the blaCTX-M-15 extended-spectrum beta-lactamase gene. Among the 91 Enterobacter cloacae isolates, seven were resistant to colistin and produced different types of carbapenemases. Surprisingly, none of the E. coli and Citrobacter spp. isolates showed resistance to colistin. This national survey including carbapenemase-producing isolates recovered in 2014 reported a high rate of colistin resistance in K. pneumoniae and E. cloacae (6.2% and 7.7%, respectively) in France

The difficult-to-control spread of carbapenemase producers in Enterobacteriaceae worldwide

Spread of carbapenemase producers in Enterobacteriaceae is now identified worldwide. Three main carbapenemases are reported which belong to three classes of ß-lactamases that are KPC, NDM and OXA-48. The main reservoirs of KPC are Klebsiella pneumoniae in the USA, Israel, Greece and Italy, of NDM are K. pneumoniae and Escherichia coli in the Indian subcontinent, and of OXA-48 are K. pneumoniae and E. coli in North Africa and Turkey. KPC producers remain mostly identified in nosocomial isolates whereas NDM and OXA-48 producers are both nosocomial and community-acquired pathogens. Control of their spread is still possible in hospital settings and relies on the use of rapid diagnostic techniques and strict implemention of hygiene measures

The Other Press, June 2, 1999

International audienceCet article propose une réflexion sur le concept de réactivité, fondée sur une investigation empirique conduite en 2010 dans des réseaux de franchise en France. Alors que la réactivité est aujourd'hui considérée comme une réponse adéquate en période de crise économique, il convient de revenir sur ce concept, pourtant bien connu en stratégie, en prenant en compte les dimensions interorganisationnelles. En effet, les entreprises ne travaillent pas seules mais sont impliquées dans des réseaux d'affaires, ce qui nécessite d'ajouter à la dimension individuelle de la réactivité, une dimension collective (ou interorganisationnelle). Notre démarche de type exploratoire, a reposé sur une analyse de contenu thématique pratiquée sur une trentaine d'entretiens effectués auprès de différents acteurs de la franchise (experts, franchiseurs et franchisés) issus de secteurs variés d'activité (réparation automobile, commerce alimentaire, immobilier etc.). Les résultats auxquels nous sommes parvenus, sont constitués des différentes facettes de la réactivité en contexte interorganisationnel : en tant que réponse à la crise, en tant que processus de décision et en tant que compétence organisationnelle

In vitro prediction of the evolution of the GES-1 β-lactamase hydrolytic activity

Resistance to ß-lactams is constantly increasing, due to the emergence of totally new enzymes, but also to the evolution of pre-existing ß-lactamases. GES-1 is a clinically-relevant extended-spectrum β-lactamase (ESBL) hydrolyzing penicillins and broad-spectrum cephalosporins, but sparing monobactams and carbapenems. However, several GES-1 variants (i.e. GES-2 and GES-5) previously identified among clinical isolates display an extended spectrum of activity toward carbapenems. To study the evolution potential of the GES-1 β-lactamase, this enzyme was submitted to in-vitro directed evolution, with selection on increasing concentrations of the cephalosporin cefotaxime, the monobactam aztreonam, or the carbapenem imipenem. The highest resistance levels were conferred by the combination of up to four substitutions. The A6T, E104K, G243A variant selected on cefotaxime, and the A6T, E104K, T237A, G243A variant selected on aztreonam, conferred high resistance to cefotaxime, ceftazidime, and aztreonam. Conversely, the A6T, G170S variant selected on imipenem conferred high resistance to imipenem and cefoxitin. Noteworthy, the A6T substitution involved in higher MICs for all ß-lactams is located in the leader peptide of the GES enzyme, therefore not present in the mature protein. Acquired cross resistance was not observed since selection with CTX or ATM did not select for resistance to IPM and vice versa. Here we demonstrated that β-lactamase GES-1 exhibits peculiar properties with a significant potential to gain activity toward broad-spectrum cephalosporins, monobactams, and carbapenems

A Universal culture medium for screening polymyxin-resistant gram-negative isolates

The colistin-containing SuperPolymyxin medium was developed for screening polymyxin-resistant Gram-negative bacteria. It was evaluated with 88 polymyxin- susceptible or polymyxin-resistant cultured Gram-negative isolates. Its sensitivity and specificity of detection were ca. 100%. The SuperPolymyxin medium is the first screening medium that is able to detect intrinsic and acquired polymyxin-resistant bacteria

Rapid detection of carbapenemase-producing Enterobacteriaceae.

To rapidly identify carbapenemase producers in Enterobacteriaceae, we developed the Carba NP test. The test uses isolated bacterial colonies and is based on in vitro hydrolysis of a carbapenem, imipenem. It was 100% sensitive and specific compared with molecular-based techniques. This rapid (<2 hours), inexpensive technique may be implemented in any laboratory