Commission Implementing Decision of 12 November 2013 on the monitoring and reporting of antimicrobial resistance in zoonotic and commensal bacteria (notified under document C(2013) 7145) (Text with EEA relevance) (2013/652/EU)

4. Specific monitoring of ESBL- or AmpC- or carbapenemase-producing Salmonella and E. coli U.K.

4.1. Method for detection of ESBL- or AmpC- or carbapenemase-producing E. coli in broilers, fattening turkeys, fattening pigs, bovines under one year of age and fresh meat of broilers, pig meat and bovine meat U.K.

For the purpose of estimating the proportion of samples containing ESBL- or AmpC- or carbapenemase-producing E. coli amongst the caecal samples collected from broilers, fattening turkeys, fattening pigs, bovines under one year of age, fresh meat of broilers, pig meat and bovine meat in accordance with point 1(d) of this Part, the following method shall apply.

For the detection of ESBL- or AmpC-producing E. coli the method shall start by a pre-enrichment step, followed by inoculation on McConkey agar containing a third generation cephalosporin in a selective concentration according to the most recent version of the detailed protocol for standardisation of the European Union Reference Laboratory for Antimicrobial Resistance(1). The microbial species E. coli shall be identified using an appropriated method.

The Member State may decide, based on the epidemiological circumstances, to test in parallel an additional selective plate that inhibits for the growth of AmpC-producing E. coli to facilitate the specific detection of ESBL-producing E. coli. When using this possibility, the results of the additional selective plate that inhibits for growth of AmpC-producing E. coli shall be kept separately when reported in accordance with point 2 of Part B.

Member States may decide to detect for carbapenemase-producing micro-organisms by using selective pre-enrichment and subsequent selective plating on carbapenem-containing media, according to the most recent version of the detailed protocol for standardisation of the European Union Reference Laboratory for AMR(2).

One presumptive ESBL- or AmpC- or carbapenemase-producing E. coli isolate obtained from each positive caecal sample and meat sample shall be tested on the first panel of antimicrobials in accordance with Table 1 and further submitted to extended susceptibility testing as set out in point 4.2 if they are resistant to cefotaxime or ceftazidime or meropenem based on the interpretative criteria (epidemiological cut-off values) listed in Table 1.

4.2. Method for further characterisation and classification of Salmonella spp. and E. coli isolates showing resistance to third-generation cephalosporins or meropenem U.K.

All presumptive ESBL- or AmpC- or carbapenemase-producing E. coli isolates identified through the selective plating described in point 4.1 as well as all those randomly selected isolates of Salmonella spp. and E. coli that after testing with the first panel of antimicrobials in accordance with Table 1, are resistant to cefotaxime or ceftazidime or meropenem, shall be further tested with a second panel of antimicrobial substances in accordance with Table 4. This panel includes cefoxitin, cefepime and clavulanate synergy test in combination with cefotaxime and ceftazidime for detection of ESBL and AmpC production. In addition the second panel also contains imipenem, meropenem and ertapenem to phenotypically verify the presumptive carbapenemase-producers.

Table 4

Panel of antimicrobial substances, EUCAST epidemiological cut-off values (ECOFFs) and clinical resistance breakpoints and concentrations ranges to be used for testing only Salmonella spp. and indicator commensal E. coli isolates resistant to cefotaxime or ceftazidime or meropenem — (Second panel)

a EUCAST epidemiological cut-off values.
b EUCAST clinical resistance breakpoints.
c 4 mg/L clavulanic acid.
d The values shall be compared to the values of Cefotaxime and Ceftazidime and interpreted according to CLSI or EUCAST guidelines regarding synergy testing.
NA : not available.
Antimicrobial	Species	Interpretative thresholds of AMR(mg/L)		Range of concentrations (mg/L)(No of wells in brackets)
		ECOFFa	Clinical breakpointb
Cefoxitin	Salmonella	> 8	NA	0,5-64 (8)
	E. coli	> 8	NA
Cefepime	Salmonella	NA	NA	0,06-32 (10)
	E. coli	> 0,125	> 4
Cefotaxime + clavulanic acidc	Salmonella	NAd	NAd	0,06-64 (11)
	E. coli	NAd	NAd
Ceftazidime + clavulanic acidc	Salmonella	NAd	NAd	0,125-128 (11)
	E. coli	NAd	NAd
Meropenem	Salmonella	> 0,125	> 8	0,03-16 (10)
	E. coli	> 0,125	> 8
Temocillin	Salmonella	NA	NA	0,5-64 (8)
	E. coli	NA	NA
Imipenem	Salmonella	> 1	> 8	0,12-16 (8)
	E. coli	> 0,5	> 8
Ertapenem	Salmonella	> 0,06	> 1	0,015-2 (8)
	E. coli	> 0,06	> 1
Cefotaxime	Salmonella	> 0.5	> 2	0,25-64 (9)
	E. coli	> 0,25	> 2
Ceftazidime	Salmonella	> 2	> 4	0,25-128 (10)
	E. coli	> 0,5	> 4

4.3. Quantitative method to assess the proportion of ESBL- or AmpC-producing E. coli U.K.

Member States, especially the Member States which have detected a high prevalence of ESBL- or AmpC-producing E. coli by the detection method set out in point 4.1, may characterise the proportion of ESBL- or AmpC-producing E. coli within the whole E. coli population.

That shall be done by enumerating ESBL- or AmpC-producing E. coli and total E. coli present in a sample using dilution methods and subsequent plating onto selective media and non-selective media, according to the most recent version of the detailed protocol of the European Union Reference Laboratory for Antimicrobial Resistance(3).

(1)

www.crl-ar.eu

(2)

See footnote 3.

(3)

See footnote 3.