Dutch patients, retail chicken meat and poultry share the same ESBL genes, plasmids and strains.

Intestinal carriage of extended-spectrum beta-lactamase (ESBL) -producing bacteria in food-producing animals and contamination of retail meat may contribute to increased incidences of infections with ESBL-producing bacteria in humans. Therefore, distribution of ESBL genes, plasmids and strain genotypes in Escherichia coli obtained from poultry and retail chicken meat in the Netherlands was determined and defined as 'poultry-associated' (PA). Subsequently, the proportion of E. coli isolates with PA ESBL genes, plasmids and strains was quantified in a representative sample of clinical isolates. The E. coli were derived from 98 retail chicken meat samples, a prevalence survey among poultry, and 516 human clinical samples from 31 laboratories collected during a 3-month period in 2009. Isolates were analysed using an ESBL-specific microarray, sequencing of ESBL genes, PCR-based replicon typing of plasmids, plasmid multi-locus sequence typing (pMLST) and strain genotyping (MLST). Six ESBL genes were defined as PA (bla(CTX-M-1) , bla(CTX-M-2) , bla(SHV-2) , bla(SHV-12) , bla(TEM-20) , bla(TEM-52) ): 35% of the human isolates contained PA ESBL genes and 19% contained PA ESBL genes located on IncI1 plasmids that were genetically indistinguishable from those obtained from poultry (meat). Of these ESBL genes, 86% were bla(CTX-M-1) and bla(TEM-52) genes, which were also the predominant genes in poultry (78%) and retail chicken meat (75%). Of the retail meat samples, 94% contained ESBL-producing isolates of which 39% belonged to E. coli genotypes also present in human samples. These findings are suggestive for transmission of ESBL genes, plasmids and E. coli isolates from poultry to humans, most likely through the food chain.

Leverstein-van Hall MA ，Dierikx CM ，Cohen Stuart J ，Voets GM ，van den Munckhof MP ，van Essen-Zandbergen A ，Platteel T ，Fluit AC ，van de Sande-Bruinsma N ，Scharinga J ，Bonten MJ ，Mevius DJ ，National ESBL surveillance group ... -  《-》

Increased detection of extended spectrum beta-lactamase producing Salmonella enterica and Escherichia coli isolates from poultry.

To gain more information on the genetic basis of the rapid increase in the number of isolates exhibiting non-wild type Minimum Inhibitory Concentrations (MICs) for cefotaxime observed since 2003, beta-lactamase genes of 22 Salmonella enterica and 22 Escherichia coli isolates from broilers in 2006 showing this phenotype were characterized by miniaturized micro-array, PCR and DNA-sequencing. Presence and size of plasmids were determined by S1-digest pulsed-field gel electrophoresis and further characterized by PCR-based replicon typing. Transfer of resistance plasmids was tested by conjugation and transformation experiments. To link resistance genes and plasmid type, Southern blot hybridization experiments were conducted. In 42 isolates, five (bla(CTX-M-1), bla(CTX-M-2), bla(TEM-20), bla(TEM-52), bla(SHV-2)) different extended spectrum beta-lactamase (ESBL)-genes and two (bla(ACC-1), bla(CMY-2)) AmpC-genes were present. Three of the detected ESBL-genes (bla(CTX-M-1), bla(TEM-52) and bla(CTX-M-2)) were located on similar types of plasmids (IncI1 and IncHI2/P) in both E. coli and Salmonella. Two other detected ESBL- and AmpC-genes bla(SHV-2) and bla(CMY-2) respectively (on IncK plasmids), were only found in E. coli, whereas the AmpC-gene bla(ACC-1) (on non-typable plasmids), and the ESBL-gene bla(TEM-20) (on IncI1 plasmids), were only detected in Salmonella. In two isolates, no ESBL- or AmpC-gene could be detected through these methods. The increase in the number of E. coli and S. enterica isolates from the gastro-intestinal tract of broilers exhibiting non-wild type MICs for cefotaxime is mainly due to an increase in IncI1 plasmids containing bla(CTX-M-1). The reason for the successful spread of this plasmid type in these species is not yet understood.

Dierikx C ，van Essen-Zandbergen A ，Veldman K ，Smith H ，Mevius D ... -  《-》

Molecular characteristics of extended-spectrum beta-lactamase-producing Escherichia coli from the Chicago area: high prevalence of ST131 producing CTX-M-15 in community hospitals.

This study was designed to characterise 30 non-duplicate extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clinical isolates from the community in the Chicago metropolitan area collected during 2008. The majority of isolates (n=28) were recovered from urine and 2 isolates were from blood. Molecular characterisation was done using the following techniques: isoelectric focusing; polymerase chain reaction (PCR) and sequencing of bla(ESBL); PCR for plasmid-mediated quinolone resistance determinants; identification of ST131; phylogenetic grouping; and replicon typing. Genetic relatedness was determined by pulsed-field gel electrophoresis (PFGE) with XbaI and repetitive sequence-based PCR (rep-PCR) typing. Twenty-six (87%) of the ESBL-producing E. coli were positive for bla(CTX-M) genes (22 CTX-M-15 and 4 CTX-M-14), whilst the remaining 4 isolates produced SHV-2. Twenty-eight isolates (93%) were non-susceptible to ciprofloxacin and 16 (53%) were positive for aac(6')-Ib-cr. Overall, 16 (53%) of the ESBL-producers belonged to clonal complex ST131 that produced CTX-M-15 or CTX-M-14. Molecular characteristics of ST131 showed that it belonged to three distinct but related PFGE clones, was derived from phylogenetic group B2 and contained IncFII type plasmids. These results illustrate that E. coli clonal complex ST131 producing CTX-M-15, CTX-M-14, OXA-1, TEM-1 and aac(6')-Ib-cr has emerged as an important cause of community-onset urinary tract infections caused by ESBL-producing E. coli isolates in the Chicago area.

Peirano G ，Costello M ，Pitout JD 《-》

Multilocus sequence typing of IncI1 plasmids carrying extended-spectrum beta-lactamases in Escherichia coli and Salmonella of human and animal origin.

García-Fernández A ，Chiaretto G ，Bertini A ，Villa L ，Fortini D ，Ricci A ，Carattoli A ... -  《-》

High prevalence of extended-spectrum-β-lactamase-producing Enterobacteriaceae in organic and conventional retail chicken meat, Germany.

Kola A ，Kohler C ，Pfeifer Y ，Schwab F ，Kühn K ，Schulz K ，Balau V ，Breitbach K ，Bast A ，Witte W ，Gastmeier P ，Steinmetz I ... -  《-》