Slide 1

. Evoluzione dellantibiotico-resistenza: miti e realt Gian Maria Rossolini Dip. Biologia Molecolare Sezione di Microbiologia Universit di Siena UO Microbiologia e Virologia Azienda Osp-Univ Senese Slide 2 MIC values Inhibition zones Broth or agar dilution tests How do we define resistance? Interpretation of results based on clinical breakpoints Interpretation of results based on clinical breakpoints Slide 3 Reference MIC/zone values for interpretation of the results of in vitro susceptibility testing The clinical breakpoints Definition of susceptibility category (S/I/R) referred to clinical use Clinical breakpoints are defined by specific committees Slide 4 Breakpoint committees in Europe CommitteeCountry BSACUnited Kingdom CA-SFMFrance CRGThe Netherlands DINGermany NWGANorway SRGASweden CLSIUSA Slide 5 Enterics / cefotaxime S BSAC United Kingdom 1 / 1 CA-SFM France 4 / 32 CRG The Netherlands 4 / 8 DIN Germany 2 / 8 CLSI U.S.A. 8 / 32 NWGA Norway 1 / 2 SRGA Sweden 0.5 / 1 with different opinions... Kahlmeter et al JAC 2003 Slide 6 December 2004 Slide 7 Slide 8 The EUCAST Mission to harmonise clinical breakpoints in Europe to determine breakpoints for new antimicrobials to provide standardised methodology for AST Slide 9 Setting clinical breakpoints for new drugs in Europe Co-ordinated process between the Company, EMEA and EUCAST When a Company applies for registration of a new agent: EUCAST defines the breakpoints EMEA decides on all other aspects EUCAST breakpoints for new drugs are the only ones included in the SPC (Summary of Product Characteristics) Slide 10 EUCAST clinical breakpoints Freely available on the WEB Defined by consensus Institutional decision body (industry has a consulting role but does not participate in the decisional process) Rationale for decision disclosed (rationale documents available) Slide 11 EUCAST vs. CLSI breakpoints: a remarkable diversity Courtesy by G. Kahlmeter Slide 12 EUCASTCLSI SR>SR> Cefepime88816 Ceftazidime88816 Imipenem4848 Meropenem2848 Pip/Tazo16 64 Aztreonam1168 Ciprofloxacin0.5112 Gentamicin4448 Tobramycin4448 Amikacin816 32 Colistin2224 EUCAST vs. CLSI breakpoints: Pseudomonas aeruginosa For S: EUCAST 5/11 lower For R: EUCAST 8/11 lower Slide 13 EUCAST vs. CLSI breakpoints: Enterobacteriaceae (beta-lactams & quinolones) EUCASTCLSI SR>SR> Cefepime18816 Ceftriaxone12832 Ceftazidime18816 Ertapenem0.5124 Imipenem2848 Meropenem2848 Pip/Tazo816 64 Levofloxacin1224 Ciprofloxacin0.5112 For S: EUCAST 9/9 lower For R: EUCAST 7/9 lower Slide 14 EUCASTCLSI SR>SR> Amikacin816 32 Gentamicin2448 Tobramycin2448 Cotrimoxazole2422 Colistin22NA Tigecycline12NA For S: EUCAST 3/4 lower For R: EUCAST 3/4 lower, 1/4 higher EUCAST vs. CLSI breakpoints: Enterobacteriaceae (other agents) Slide 15 EUCAST vs. CLSI Will the change from CLSI to EUCAST breakpoint system significantly affect the epidemiology of antibiotic resistance? Slide 16 EUCAST vs. CLSI A comparative analysis of AST results interpreted according to CLSI or EUCAST Data source: historical records from clinical microbiology service, Siena University Hospital (year 2008) Slide 17 Pseudomonas aeruginosa Gentamicin (N = 295) 2481632 64 EUCAST CLSI MIC (mg/L) EUCAST: R CLSI: I Slide 18 Pseudomonas aeruginosa Amikacin (N = 296) 2481632 64 EUCAST CLSI MIC (mg/L) EUCAST: R CLSI: I EUCAST: I CLSI: S Slide 19 Pseudomonas aeruginosa Ceftazidime (N = 294) 124816 32 EUCAST CLSI MIC (mg/L) EUCAST: R CLSI: I Slide 20 Pseudomonas aeruginosa Meropenem (N = 216) 2481632 64 EUCAST CLSI MIC (mg/L) EUCAST: I CLSI: S Slide 21 Pseudomonas aeruginosa Pip/Tazo (N = 289) 2481632 64 EUCAST CLSI MIC (mg/L) EUCAST: R CLSI: S Slide 22 Pseudomonas aeruginosa Aztreonam (N = 133) 124816 32 EUCAST CLSI MIC (mg/L) EUCAST: I CLSI: S Slide 23 Pseudomonas aeruginosa Ciprofloxacin (N = 295) 0.250.5124 8 EUCAST CLSI MIC (mg/L) EUCAST: R CLSI: I EUCAST: I CLSI: S Slide 24 Pseudomonas aeruginosa CLSI vs. EUCAST % susceptibility Antibiotics Slide 25 MRSA impact (USA) Boucher & Corey Clin Infec Dis 2008 a in hospital deaths Slide 26 Resistance trends in major pathogens Europe EARSS annual report, 2007 MRSA Countries 8/30 14/30 = 8/30 14/30 = E. coli R to 3GC 23/30 1/30 6/30 = 23/30 1/30 6/30 = 2008: 2/31 10/31 19/31 = 2008: 2/31 10/31 19/31 = 2008: 21/30 0/30 9/31 = 2008: 21/30 0/30 9/31 = Slide 27 Resistance trends in major pathogens Europe EARSS annual report, 2007 MDR E. coli (R to 3GC,AG,FQ) MDR E. coli (R to 3GC,AG,FQ) 24/30 0/30 6/30 = 24/30 0/30 6/30 = Countries E. coli R to 3GC 23/30 1/30 6/30 = 23/30 1/30 6/30 = Slide 28 The growing challenge of resistant Gram-negatives MRSA and VRE rates have leveled off or decreasing in several European countries Resistant Gram-negatives are increasing in most European countries Rossolini & Mantengoli, CMI 2008 Major challenges: Enterobacteriaceae ESBL/AmpC, MDR, XDR (ESC/FQ/AG/NEM) Pseudomonas aeruginosa and Acinetobacter MDR, XDR (COL-S only) Slide 29 EARSS database Year % resistant to 3GC K. pneumoniae ESBLs: increasing trends Slide 30 EARSS database Year % resistant to 3GC E. coli ESBLs: increasing trends Slide 31 % Spanu et al. - AAC 2002; Luzzaro et al. - JCM 2006; OASIS study, data on file ESBL-producing Enterobacteriaceae, Italy Slide 32 Suspect ESBL 2003: Proteus mirabilis (isolates from UTIs and ulcers) Aztreonam Ceftazidime Cefotaxime Ceftriaxone Amoxi/Clav Resistant to 3rd gen. ceph. but ESBL-negative Ampicillin >128 R Amoxi/Clav 32 R Pip/Tazo 4 S Cephalotin 32 R Cefotaxime 64 R Ceftazidime 32 R Cefepime 2 Ertapenem 0.12 S Amikacin 2 S Gentamicin 4 S Ciprofloxacin >32 R Levofloxacin >32 R MIC (mg/L) R S Slide 33 . P. mirabilis resistant to 3rd gen. cephalosporins Luzzaro et al IJAA 2009 Same clone detected in LTCFs By clonal expansion Slide 34 Luzzaro et al IJAA 2009 Clinical features of infections caused by the P. mirabilis CMY-16+ Mean age: 7515 yrs (7616 for ESBL+; 5728 for susceptible strains) Female/male ratio: 1.1 (1.6 for ESBL+; 2.1 for susceptible strains) 51%37% Patients 80% Sources Slide 35 2007-2008: P. mirabilis CMY+ spreading in Italy 2007-2008: P. mirabilis CMY+ spreading in Italy Clonally related isolates detected in Greece and Poland: an internationally spreading clone DAndrea et al unpublished >30 cases from BSIs Slide 36 Courtesy of Vincent Jarlier, Sept 2009 (modified) ESBLs/AmpC and carbapenem overuse Increased # ESBL/AmpC cases Increased Carb-R strains Cross transmission of Carb-R strains Selection of Carb-R strains Increased carbapenem use Slide 37 Production of: - CTX-M-15 ESBL - SHV-11 - (OXA-9) (TEM-1) Production of: - CTX-M-15 ESBL - SHV-11 - (OXA-9) (TEM-1) DAndrea et al. 19th ECCMID 2007-2008: emergence of MDR Klebsiella pneumoniae ERT-R from several hospitals Ampicillin >16 R Amoxi/Clav >16 R Pip/Tazo >64 R Cefotaxime >16 R Ceftazidime >32 R Cefepime >16 R Aztreonam >16 R Imipenem 1 Meropenem 2-4 Ertapenem >4 R Amikacin >32 R Gentamicin >8 R Tobramycin >8 R Ciprofloxacin >32 R Levofloxacin >32 R TMP/SXT >2 R Tigecycline 1 - 2 ColistinSlide 38 Ampicillin >16 R Amoxi/Clav >16 R Pip/Tazo >64 R Cefotaxime >16 R Ceftazidime >32 R Cefepime >16 R Aztreonam >16 R Imipenem 1 R Meropenem 2-4 R Ertapenem >4 R ESBL positive Amikacin >32 R Gentamicin >8 R Tobramycin >8 R Ciprofloxacin >32 R Levofloxacin >32 R TMP/SXT >2 R Tigecycline 1 - 2 S ColistinSlide 39 KPC-2 K. oxytoca KPC-2 K. oxytoca Yigit et al. AAC 2003 Slide 40 22% of isolates resistant to: - Aminoglycosides - Fluoroquonolones - 3rd 4th gener. Cephems - Carbapenems Klebsiella pneumoniae Susceptibility only to: - Colistin - Tigecycline Due to spread of KPC carbapenemases Brooklyn, New York Landman et al JAC 2007 Slide 41 KPC-type carbapenemases in Israel: a major problem Nationwide outbreak Carbapenem resistance rates in K. pneumoniae from Israel: 2006: 11% 2007: 22% 2008: 19% EARSS database Slide 42 KPC-type carbapenemases: a new pandemic? Two cases, one with Israel connection Clonally related 7 cases 4 from Greece 2 from Israel Clonally related Nordmann et al. Lancet ID 2009 Villegas et al. AAC 2007 Tsakris et al. JAC 2008 Hawser et al. IJAA 2009 Literacka et al. AAC 2009 Intercontinental spread of ST258 KPC+ clone Slide 43 KPC-type carbapenemases: emerging in Italy Giani et al - JCM 2009 Florence Oct 2008: KPC-3 positive K. pneumoniae ST258 isolated from a cIAI (high-level carbapenem resistance) No epidemiological link with areas of endemicity, but patient cared for by a trainee from Israel Lecco May 2009: KPC positive K. pneumoniae Patient transferred from another hospital Large outbreak ongoing in that hospital (26 patients colonized or infected), variable carbapenem resistance Luzzaro et al - unpublished Santoriello et al - unpublished Mostly by clonal spread (ST258), but at least two clones and also in Enterobacter Additional reports Slide 44 Carbapenem-resistant K. pneumoniae, Greece Production of VIM-1 MBL Production of VIM-1 MBL Multiple clones Often susceptible only to colistin and tigecycline (XDR) Vatopoulos et al. - Eurosurveillance 2008 Psichogiou et al. JAC 2008 Slide 45 KPC-type (active-site serine, class A) OXA-type (active-site serine, class D) Metallo--lactamases (class B) Carbapenemases of clinical relevance Slide 46 GM COL AK TOB FEP IPM MEM CAZTZP ATM CIP PRL Lauretti et al. AAC 1999 Cornaglia et al. CID 2000 VERONA 1997 VIM-1 MBL-producing index strain VR-143/97 (ser. O11; ST227) VIM-1 MBL-producing index strain VR-143/97 (ser. O11; ST227) Slide 47 Acquired MBLs in Pseudomonas aeruginosa first Italian nationwide survey VARESE 2.6% PAVIA 1.3% CREMONA 0.6% PERUGIA 1.1% SASSARI 0.9% ROME 0.3% AVELLINO 1.4% NEAPLES 9.2% FOGGIA 1.2% GENOA 0% TURIN 0% LAQUILA 0% 2004: Overall prevalence 1.3% 2004: Overall prevalence 1.3% Rossolini et al. AAC 2008 2008: Overall prevalence 7% 2008: Overall prevalence 7% Luzzaro et al. - unpublished Slide 48 CLSI soon replaced by EUCAST: resistance rates will be affected in some cases Resistance in Gram-negatives: now a major problem XDR phenotypes not only in Pseudomonas and Acinetobacter but also among enterobacteria Multiple resistance mechanisms: not easily deducible from the antibiotype Open issues in: lab detection, reporting, infection control and treatment Conclusions