P1030 Low prevalence of TEM-type ESBLs among nosocomial strains of Enterobacteriaceae in Russia

S276 P1029 Explosive emergence of CTX-M-15 extended-spectrum b-lactamase in Enterobacteriaceae in Kuwait L. Poirel, V. Rotimi, S. Bernabeu, W. Jamal, P. Nordmann (Le Kremlin Bicetre, FR; Kuwait City, KW) Objectives: Emergence of expanded-spectrum b-lactamases (ESBL) of the CTX-M group in Enterobacteriaceae has been reported worldwide. Our goal was to identify ESBL genes from a collection of clinicallysignificant ESBL-producing enterobacterial isolates recovered from the Mubarak hospital in Kuwait City, Kuwait from 2002 to 2004. Methods: PCR with primers specific for several ESBL genes (blaTEM, blaSHV, blaCTX-M, blaVEB, and blaPER) were used for screening followed by sequencing of PCR products. Primers specific for mobile elements known to be at the origin of blaCTX-M genes acquisition were also used. Strains (one per patient) were collected during a three-year period. ESBL production was suggested by results of liquid medium VITEK 2 analyzer and confirmed by synergy tests performed on solid agar plates. Plasmid profiles analysis was determined by the Kieser method followed by Southern hybridisation with blaCTX-M specific probes. Results: 598 enterobacterial isolates were recovered during the studied period with 63 ESBL-producers (10.5%). Noteworthy, in 2002 and 2003 respectively, only 2 out of 57 (3.5%) and 6 out of 265 (2.3%) enterobacterial isolates were ESBL producers, whereas they were 55 out of 276 (20%) in 2004. ESBL producers were mostly Escherichia coli (n = 29), Klebsiella pneumoniae (n = 19). In addition, there were several Enterobacter cloacae (n = 4), Enterobacter aerogenes (n = 3), Proteus mirabilis (n = 6), Citrobacter freundii (n = 2) and Serratia marcescens (n = 1). They were from different hospital units, but mostly from Medicine, Surgery and Nephrology departments. The ESBL determinants were mostly of the CTX-M group (50 out of 63), with CTX-M-15 being the main ESBL (46 out of 50). Insertion sequence ISEcp1 was identified systematically upstream of the blaCTX-M-15 gene. The other CTX-M variants were CTX-M-2 and CTX-M-9. The other ESBL-type were mostly SHV-type enzymes, and one isolate was VEB-1 positive. An heterogeneous pattern of blaCTX-M-borne plasmids was observed that indicated that the dissemination of those resistance determinants were not related to dissemination of a single plasmid. Conclusion: This study constitutes the first survey on ESBL spread in Kuwait. Dissemination of CTX-M-15 producers was identified as observed worldwide with a threatening increasing detection rate.

P1030 Low prevalence of TEM-type ESBLs among nosocomial strains of Enterobacteriaceae in Russia L.N. Ikryannikova, E. Shitikov, E.N. Ilina, M.V. Edelstein, V.M. Govorun (Moscow, Smolensk, RU) Objectives: Production of extended-spectrum b-lactamases (ESBLs) in Enterobacteriaceae is one of the most prevalent mechanisms of resistance to oxyimino-b-lactams. Among others enzymes, the numerous mutant variants of TEM-type penicillinases (e.g. TEM-1 and TEM-2) possess ESBL phenotype. In this study we evaluated a contribution of TEMtype ESBLs to the development of resistance to oxyimino-b-lactams in nosocomial strains of Enterobacteriaceae collected in Russian Federation. Methods: A total of 718 ESBL-producing nosocomial isolates of 10 different genera of the family Enterobacteriaceae, mainly Klebsiella pneumoniae (47.4%) and Escherichia coli (40.5%), collected in the hospitals from Central (n = 235), North-West (n = 52), Volga (n = 39), South (n = 95), Ural (n = 62), Siberian (n = 175) and Far-Eastern (59) regions of Russian Federation as part of the national surveillance of antimicrobial resistance in ICU pathogens in 2002–2004 were investigated. The ESBL phenotype of these isolates was inferred based on the MIC of at least one of the oxyimino-cephalosporins (cefotaxime, ceftazidime and cefepime) 2 mg/L and positive results of the MIC synergy test (according to CLSI), or of the double-disk synergy with

17th ECCMID / 25th ICC, Posters clavulanic acid. The complete coding sequences of TEM b-lactamasecoding genes were amplified by PCR and directly sequenced using the automated fluorescent dideoxy terminator sequencing. Results: Three hundred and seventy three (51.9%) of the studied isolates were PCR-positive for blaTEM genes. Of these, 372 were found to possess TEM-penicillinase genes, including 368 – TEM-1 (98.7%), two – TEM-2, one – TEM-57 (Gly92Asp), and one – TEM-117 (Leu21Phe). Only one strain had a single Arg164His substitution consistent with the TEM-29 ESBL. Conclusion: This is a first report of a distribution of TEM-type ESBLs in Russian nosocomial strains of Enterobacteriaceae expressing ESBL phenotype. Our results show that TEM-type ESBLs are not a common cause of resistance in Russian Federation. P1031 Prevalence of faecal carriage of metallo-b-lactamase producing Enterobacteriaceae in a Spanish hospital T. Curiao, M. Tato, A. Valverde, A. Novais, F. Baquero, T.M. Coque, R. Canton (Madrid, ES) Background: Metallo-b-lactamase (MBL) producing Enterobacteriaceae have been recognized in different European countries, including Greece, France, and Spain. We recently described a polyclonal outbreak involving these isolates in our hospital in Madrid (Tato et al. 46th ICAAC, 2006; abstract C2−66). In this study we investigated the intestinal colonisation by MBL producing isolates of hospitalised and ambulatory patients in our geographic area. Methods: A total of 600 faecal samples from 569 hospitalised (20%) and ambulatory (80%) patients who attended in our hospital (January-April 2006) were studied. Aliquots of saline faecal suspension were cultured in MacConkey supplemented with ceftazidime (4 mg/L) agar plates and in Luria-Bertani (LB) supplemented with imipenem (2 mg/L) broth. Isolates from positive cultures were screened for MBL production by a double disk synergy test (DDST) using imipenem (10 mg), ceftazidime (30 mg) and EDTA (1900 mg) disks. Bacterial identification and antimicrobial susceptibility were performed using the WIDER system (Fco. Soria Melguizo, Madrid, Spain). MLB characterisation (blaVIM and blaIMP PCR, sequencing, and IEF) and PFGE were performed in isolates with positive DDST. Results: A positive faecal carriage with MLB producing isolates was observed in four patients (0.7%) hospitalised (3.5%) at surgical (n = 1) and medical (n = 1) wards and ICUs (n = 2). No colonised patients were detected in outpatients. Proposed method for detection of MBL producers was efficient. All MBL producers were recovered on both supplemented MacConkey agar plates and LB broth and identified as Enterobacter cloacae (n = 2) and Klebsiella pneumoniae (n = 2). All of them produced VIM-2 enzyme and belonged to epidemic clones detected in our hospital. Unlike E. cloacae, patients with K. pneumoniae colonisation were also infected by this clone. Conclusions: MBL (VIM-2) producing Enterobacteriaceae have emerged in our geographic area in hospitalised patients. Prevalence of colonised patients (3.5%) in our institution represents a clinical concern for the maintenance of epidemic clones and source for infections. Intervention strategies of containment of MBL producing isolates should include faecal carriage studies. P1032 Extended-spectrum b-lactamase producing Enterobacteriaceae in a Swiss university hospital: molecular characterisation and susceptibility to ertapenem T. Bruderer, A.F. Widmer, M. Flury, S. Oezcan, M. Jutzi, R. Frei (Basle, CH) Objectives: First, to determine the molecular types of extended-spectrum b-lactamases (ESBLs) in Enterobacteriaceae at the University Hospital Basel, Switzerland. Secondly, to assess the activity of ertapenem against ESBL-producing strains. Methods: Between 1/1/2003 and 31/12/2005, all consecutive clinical Enterobacteriaceae isolates were screened by use of 4 ESBL markers