Friday, 30 March 2012

E.coli producing VIM-1 carbapenemase on German pig farm


Bad news from Germany.

Abstract and access to full report here


Escherichia coli producing VIM-1 carbapenemase isolated on a pig farm

1.        Jennie Fischer1, 
2.        Irene Rodríguez1, 
3.        Silvia Schmoger1, 
4.        Anika Friese2, 
5.        Uwe Roesler2,
6.        Reiner Helmuth1 and 
7.        Beatriz Guerra1,*


...Carbapenems are one of the most critically important antimicrobials considered as drugs of last choice in clinical settings. However, during the last few years, the prevalence of resistance to these antimicrobial agents, especially inPseudomonas and Enterobacteriaceae, has been increasing worldwide.13 In Gram-negative bacteria, the mechanisms of resistance include the production of β-lactamases (carbapenemases), changes in the permeability of the membranes (i.e. loss of porins) and efflux pumps. Within the carbapenemases, the class B metallo-β-lactamases, such as VIM, IMP and NDM, play an important role because of their worldwide spread among different bacterial species, which is based on their location on mobile genetic elements.2,4,5
Currently, the national RESET project (www.reset-verbund.de) performs several longitudinal and cross-sectional studies of German farms, and potential extended spectrum β-lactamase (ESBL)-carrier organisms are collected (using MacConkey agar containing 1 mg/L cefotaxime as selective medium). All isolates sent to the Federal Institute for Risk Assessment for further analyses (n = 221) were tested for their antimicrobial susceptibility by the CLSI disc diffusion method (CLSI M2-A10 and M100-S21). They were analysed against a panel of 17 β-lactams (Oxoid, Wesel, Germany), including ampicillin (10 μg), piperacillin (100 and 30 μg), ticarcillin (75 μg), cefalotin (30 μg), cefuroxime (30 μg), ceftiofur (30 μg), ceftriaxone (30 μg), ceftazidime (30 and 10 μg), cefotaxime (30 and 5 μg), cefpodoxime (10 μg), cefepime (30 μg), cefoxitin (30 μg), aztreonam (30 μg), imipenem (10 μg), ertapenem (10 μg), meropenem (10 μg) and amoxicillin/clavulanic acid (30 μg). The 30, 10 and 5 μg amounts for piperacillin, ceftazidime and cefotaxime, respectively, are the disc concentrations recommended by EUCAST (www.eucast.org). The isolates were also tested for their susceptibility …