Université de Fribourg

Acquisition of extended-spectrum β-lactamase GES-6 leading to resistance to ceftolozane-tazobactam combination in Pseudomonas aeruginosa

Poirel, Laurent ; Ortiz De La Rosa, José-Manuel ; Kieffer, Nicolas ; Dubois, Véronique ; Jayol, Aurélie ; Nordmann, Patrice

In: Antimicrobial Agents and Chemotherapy, 2019, vol. 63, no. 1, p. e01809-18

A clinical Pseudomonas aeruginosa isolate resistant to all β-lactams, including ceftolozane-tazobactam and carbapenems, was recovered. It belonged to sequence type 235 and produced the extended-spectrum β-lactamase (ESBL) GES-6 differing from GES-1 by two amino acid substitutions (E104K and G170S). GES-6 possessed an increased hydrolytic activity toward carbapenems and to ceftolozane and a ...

Université de Fribourg

Detection of colistin-resistant Gram-negative rods by using the SuperPolymyxin medium

Jayol, Aurélie ; Poirel, Laurent ; André, Catherine ; Dubois, Véronique ; Nordmann, Patrice

In: Diagnostic Microbiology and Infectious Disease, 2018, vol. 92, no. 2, p. 95–101

The commercial SuperPolymyxin medium (ELITechGroup, Puteaux, France), currently licensed in Europe, is aimed to screen for either intrinsic or acquired colistin resistance in Gram negatives. It was tested for screening colistin-resistant Gram- negative rods from bacterial cultures of 145 colistin-resistant and 86 colistin- susceptible Gram-negative rods isolates. It exhibited a sensitivity and...

Université de Fribourg

Evaluation of three broth microdilution systems to determine colistin susceptibility of Gram-negative bacilli

Jayol, Aurélie ; Nordmann, Patrice ; André, Catherine ; Poirel, Laurent ; Dubois, Véronique

In: Journal of Antimicrobial Chemotherapy, 2018, p. -

The broth microdilution (BMD) method is currently the recommended technique to determine susceptibility to colistin.Objectives: We evaluated the accuracy of three commercialized BMD panels [Sensititre (ThermoFisher Diagnostics), UMIC (Biocentric) and MicroScan (Beckman Coulter)] to determine colistin susceptibility.Methods: A collection of 185 isolates of Gram-negative bacilli (133 colistin...

Université de Fribourg

Prevalence of faecal carriage of colistin-resistant Gram-negative rods in a university hospital in western France, 2016

Saly, Marion ; Jayol, Aurélie ; Poirel, Laurent ; Megraud, Francis ; Nordmann, Patrice ; Dubois, Véronique

In: Journal of Medical Microbiology, 2017, vol. 66, no. 6, p. 842–843

Plasmid-mediated and chromosomally-encoded colistin resistance is increasingly being reported worldwide. We aimed to determine the prevalence of faecal carriage of colistin-resistant Gram-negative rod isolates in a university hospital in western France. From February to May 2016, rectal swabs from 653 patients hospitalized in various clinical settings were recovered and subsequently screened...

Université de Fribourg

Hafnia, an enterobacterial genus naturally resistant to colistin revealed by three susceptibility testing methods

Jayol, Aurélie ; Saly, Marion ; Nordmann, Patrice ; Ménard, Armelle ; Poirel, Laurent ; Dubois, Véronique

In: Journal of Antimicrobial Chemotherapy, 2017, vol. 72, no. 9, p. 2507–2511

ObjectivesTo determine the susceptibility to colistin of Hafnia alvei and Hafnia paralvei, and to compare methods for colistin resistance detection in the Hafnia genus.MethodsA collection of 25 Hafnia isolates was studied. Species were identified by using 16S rRNA gene sequencing with subsequent phylogeny analysis. Susceptibility to colistin was determined using the broth microdilution (BMD)...

Université de Fribourg

Ceftazidime/avibactam alone or in combination with aztreonam against colistin-resistant and carbapenemase-producing Klebsiella pneumoniae

Jayol, Aurélie ; Nordmann, Patrice ; Poirel, Laurent ; Dubois, Véronique

In: Journal of Antimicrobial Chemotherapy, 2017, p. -

The spread of carbapenemase-producing Klebsiella pneumoniae is a major public health concern since such isolates are basically resistant to most available antibiotics, including β-lactams, fluoroquinolones and aminoglycosides.1 Infections due to carbapenemase-producing K. pneumoniae are therefore commonly treated with a regimen containing colistin.1 However, acquired resistance to colistin...

Université de Fribourg

High-level resistance to colistin mediated by various mutations in the crrb gene among carbapenemase-producing klebsiella pneumoniae

Jayol, Aurélie ; Nordmann, Patrice ; Brink, Adrian ; Villegas, Maria-Virginia ; Dubois, Véronique ; Poirel, Laurent

In: Antimicrobial Agents and Chemotherapy, 2017, vol. 61, no. 11, p. e01423-17

Mutations in crrAB genes encoding a two-component regulator involved in modifications of lipopolysaccharide were searched for among a collection of colistin- resistant Klebsiella pneumoniae isolates. Four isolates, respectively, producing carbapenemases NDM-1, OXA-181, or KPC-2 showed mutated CrrB proteins compared with those in wild-type strains. Complementation assays with a wild-type CrrB...

Université de Fribourg

Comparison of methods for detection of plasmid-mediated and chromosomally encoded colistin resistance in Enterobacteriaceae

Jayol, Aurélie ; Nordmann, Patrice ; Lehours, Philippe ; Poirel, Laurent ; Dubois, Véronique

In: Clinical Microbiology and Infection, 2017, p. -

Objectives: Because of the emergence of plasmid-mediated (mcr-1 and mcr-2 genes) and chromosomally encoded colistin resistance, reliable methods for detecting colistin resistance/susceptibility in routine laboratories are required. We evaluated the respective performances of the BD Phoenix automated system, the newly developed Rapid Polymyxin NP test and the broth microdilution (BMD) reference...

Université de Fribourg

Rapid detection of polymyxin-resistant Enterobacteriaceae from blood cultures

Jayol, Aurélie ; Dubois, Véronique ; Poirel, Laurent ; Nordmann, 2 Patrice

In: Journal of Clinical Microbiology, 2016, p. JCM.00918-16

Enterobacterial strains resistant to polymyxins are increasingly reported worldwide. Conventional methods for detection of colistin-resistant isolates such as broth microdilution remain time-consuming (24 to 48 h), and methods such as disc diffusion and E-test are not reliable. Recently, the Rapid Polymyxin NP test was developed for a rapid identification of polymyxin-resistant...