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1 ESCMID Postgraduate Technical Workshop Antimicrobial susceptibility testing and surveillance of resistance in Gram-positive cocci: laboratory to clinic Current epidemiology of invasive enterococci in Europe Luis Martínez-Martínez Service of Microbiology Univ. Hosp. Marqués de Valdecilla Dept. of Molecular Biology University of Cantabria Santander, Spain Zagreb, Croatia, June 17, 2012

2 Enterococcus spp.: Clinical Relevance Enterococcus faecalis Enterococcus faecium Other species Urinary tract infections Wound infections Bacteraemia Infective endocarditis

3 THE EXTREME CLINICAL SITUATION. USA 1980s/early 1990s: E. faecalis: 90%; E. faecium: 5 10% Today. E. faecium: up to 30-35% Healthcare-associated infections E. faecium: Up to 90% Ampicillin-R; 80% vancomycin-r E. faecalis. Ampicillin-R: 4%; vancomycin-r: 7%

4 Enterococcus spp.: Intrinsic Resistance Organism FUS CEPHAL AMG ERY CLI Q/D VAN SUL E. faecalis R R R (LLR) E. gallinarum E. casseliflavus E. faecium R R AAC(6 ) R R R R R R R R R R R R R R R Leclerc R et al. EUCAST expert rules. Clin Microbiol Infect 2011

5 Exceptional phenotypes of Enterococcus spp. ORGANISM Enterococcus spp. E, faecalis E. gallinarum E. casseliflavus E. avium AGENT Resistant to linezolid, daptomycin, and tigecycline. Resistant to teicoplanin but not vancomycin Susceptible to quinupristin dalfopristin. Consider likelihood of misidentification. If also resistant to ampicillin, it is almost certainly E. faecium E. faecium Resistant to quinupristin dalfopristin. Consider likelihood of misidentification, especially if also susceptible to ampicillin Leclerc R et al. EUCAST expert rules. Clin Microbiol Infect 2011

6 Warning: For Enterococcus spp., Cephalosporins, Aminoglycosides (except for high-level screening) Clindamycin Trimethoprim-sulfamethoxazole may appear active in vitro, but are not effective clinically and should not be reported as susceptible CLSI document M100-S22; 2012

7 GROUP Routine testing of Enterococcus by CLSI (FDA clinical indications) AGENT A: Primary Test and Report Ampicillin, Penicillin B: Primary Test Report Selectively Daptomycin (MIC only), Linezolid, Vancomycin C: Supplemental Report Selectively HLR screen-gentamicin HLR screen-streptomycin U: Supplemental for Urine Only Ciprofloxacin, Levofloxacin, Norfloxacin Nitrofurantoin Tetracycline CLSI document M100-S22; 2012

8 Enterococcus spp.: Acquired Resistance High-level resistance to β-lactams Glycopeptides High-level resistance to aminoglycosides Oxazolidinones Lipopeptides Tigecycline [Quinolones] Macrolides Tetracyclines Streptogramins

9 GR-E. faecium strains: Host-specific properties Nosocomial strains genetically unrelated to faecal strains of nonhospitalized humans. Nosocomial strains in CC17 Enterococcus faecium: Clonal Complexes Distributed worldwide Ampicillin R; ciprofloxacin-r (high level); High percentage of Vancomycin-R vana (resistance to teicoplanin and vancomycin) on Tn1546 Specific virulence genes: community acquired VRE largely lacked the esp gene Enriched in the purk1 allele Enriched in IS elements Megaplasmids in most contemporary E. faecium

10 E. faecium from animals E. faecium CC17 from dogs; occasionally from other animals (anthropo-zoonotic transfer or dogs are a risk?) esp and hyl were not detected. Resistance profiles differed from those previously described for clinical human E. faecium from pigs related to CC5 vana E. faecium isolates from pigs from Europe and USA E. faecium CC5 isolates also in patients with UTI, and in fecal samples from community persons. E. faecium from animals can in some occasions affect humans, but most likely are important because the can provide resistance genes to other pathogenic enterococci.

11 Enterococcus faecium.: Resistance and the non-human reservoir Role of avoparcin? Denmark, 1994: Humans: 24 kg of vancomycin Animals: 24 tons of avoparcin Australia, : Humans: 582 kg of vancomycin/year Animals: 62,6 tons of avoparcin /year Avoparcin banning: Denmark and Norway (1995), Germany (1996), the rest of the EU and Korea (1997), Taiwan and New Zealand (2000) BUT Vancomycin-R E. faecium persisted in animals after avoparcin banning (Co-selection with tylosin, copper sulphate, tetracyclines,?) A. M. Hammerum, CMI 2012, online

12 Enterococcus faecium: Resistance and the non-human reservoir Quinu dalfo-r E. faecium in non-hospitalized humans, UK (Q/D and other streptogramins not licensed in the UK for use in humans!) Virginiamycin use in animals? Virginiamycin banned in Denmark (1998) and in all of the EU (1999). Use was restricted to therapeutic purposes in Australia (2008)

13 HYPOTHESIS: Enterococcus faecium: Clonal Complexes Non-epidemic expansion of particular CC17 clones before acquisition (multi-step process) of vancomycin resistance and putative virulence traits. No efficient method available to identify non-epidemic VRE E. faecium have not evolved recently from a single common ancestor: The designation of CC17 (simply) as a hospitalassociated CC may be erroneous.

14 Enterococcus faecalis: Clonal Complexes E. faecalis causing hospital outbreaks: CC2, CC9, CC87, CC21. CC2 (ST6) E. faecalis in pigs and in healthy infants ST16 E. faecalis: healthy humans, patients, animals Some isolates present high-level gentamicin-r. Other E. faecalis strains with different STs isolated from animals Virulence Genes of E. faecalis (gelatinase, cytolysin, enterococcal surface protein Esp and aggregation substance) frequently found in nonclinical E. faecalis There are not clear distinction between pathogenic and nonpathogenic clones in E. faecalis.

15 Enterococcus faecalis. Clonal Complexes in Spain

16 Proportion of Aminopenicillins (R+I) resistant Enterococcus faecium isolates in participating countries in Global:

17 Proportion of Aminopenicillins (R+I) resistant Enterococcus faecalis isolates in participating countries in 1991, 2006, 2010 Global:

18 Mostly due to mutations causing modification and/or overproduction of some PBPs (PBP4 in E. faecalis and PBP5 in E. faecium). This is by far more frequent in E. faecium Two distinct E. faecium lineages, with different ampicillin susceptibility, probably representative of commensal and hospital-associated clades? Beta-lactamase production Uncommon: Ampicillin Resistance in Enterococcus Reduced penicillin susceptibility and full ampicillin susceptibility. Some isolates, additionally resistant to gentamicin (ST6) and had indistinguishable or closely related PFGE

19 E. faecalis: Uncommon phenotypes of beta-lactam susceptibility (Hippokration University Hospital, Greece) Metzidie E et al, JAC

20 Beta-lactamase in E. faecium Modena, Italy, 2010 MIC of AMP: 8->=32 mg/l bla operon (blazblaiblar1) on the chromosome Related to Tn552 of S. aureus Other resistance genes (vanb2) Very slow reaction (pale color at 24 h) 8 different PFGE profiles 6 different lineages, all clustering in CC17 Sarti M et al, JCM

21 Proportion of Vancomycin (R) resistant Enterococcus faecium isolates in participating countries in Global:

22 Proportion of Vancomycin (R) resistant Enterococcus faecalis isolates in participating countries in Global:

23 Glycopeptide Resistance in Enterococcus 1986 in France and UK. Later in USA. van genes: A to M, after the type of D-amino acid ligase Modified peptidoglycan. No D-ala-D-ala dipeptide, but D-ala-D-lactate or D-ala-D-ser. vana and vanb the most important. Dissemination of vana clusters is mediated by Tn1546-like elements. VRE-MRSA cocolonization or coinfection common (up to 20% of all patients studied) in some regions. Transmission (Inc18-like vana plasmid) of the vancomycin-r transposon from VRE to MRSA: VRSA!!!

24 High-level ciprofloxacin resistance among hospital-adapted E. faecium (CC17) 609 clinical E. faecium isolates from a German hospital ( ) high-level resistance was defined as MIC>16 mg/l 26 different MLST types (all CC17) High-level CIP-Res related to mutations in both gyra and parc, Eleven different allele types or combinations thereof were identified Ciprofloxacin (MICs) for the 609 E. faecium from German hospital patients ( ).

25 Risk factors for VRE Elderly persons Severely ill patients Previous treatment with extensive courses of antibiotic Intensive care nits and transplant wards

26 Proportion of High level gentamicin (R) resistant Enterococcus faecium isolates in participating countries in Global:

27 Proportion of High level gentamicin (R) resistant Enterococcus faecalis isolates in participating countries in Global:

28 Linezolid resistance in Enterococcus Mutations in the domain V of 23S rrna (G2576T). Additional mutations include: T2500A, C2192T, G2447T, A2503G, T2504C, G2505A, G2766T and C2461T. Mutations in the ribosomal proteins L3 and L4 cfr (chloramphenicol-florfenicol resistance gene ): Methyltransferase (A2503 in the 23S rrna) Díaz L et al. AAC 2012, 56: 3917

29 linezolid-r enterococci and linezolid consumption. Southwest Germany; June 2004 to June 2006 Schulte B et al, Epidemiol. Infect