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P133 Localization of resistance genes on the multiple-drug resistance plasmids in Escherichia coli isolated from beef cattle
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Posters / International Journal of Antimicrobial Agents 42S2 (2013) S41–S159
Conclusion: Multidrug resistant K. pneumoniae isolates habouring bla OXA-48 and bla NDM has emerged in Saudi Arabia. The identification of colistin resistant isolates is of major concern. P132 Clonal dissemination of OXA-23-producing extensively drug resistant Acinetobacter baumannii at a teaching hospital Y. Li1 *, Q. Guo1 , X. Ye1 , D. Zhu1 , M. Wang1 . 1 Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China E-mail address : [email protected] Introduction: Extensively drug resistant Acinetobacter baumannii presents a serious therapeutic and infection control challenge. We describe the molecular and clinical characteristics of 106 consecutive non-duplicate extensively drug resistant (XDR) Acinetobacter baumannii at a hospital in Shanghai, China. Methods: One-hundred and six clinical isolates of XDR A. baumannii were collected from January to December 2010. Antimicrobial susceptibilities were determined by agar dilution method. The prevalence of the carbapenemase genes were investigated by polymerase chain reaction (PCR)amplification. Genetic relatedness of isolates was determined by multilocus sequence typing (MLST) and Enterobacterial repetive intergenic consensus-PCR (ERIC-PCR). A case-control study was performed from January to December 2010. Cases were defined as patients clolonized or infected by XDR A. baumannii , and controls were patients without A. baumannii isolation, in an 1:1 proportion. Results: All 106 A. baumannii isolates were resistant to all antimicrobial agents tested, except colistin and tigecycline. All isolates possessed bla OXA-51-like and bla OXA-23-like. One-hundred and five isolates belonged to clonal complex 92. According to ERIC-PCR, clone A1 and A2 were the predominant clones, comprising 75.5% of all isolates. Neurosurgical patients comprised 48.4% of all patients, especially brain surgery (44.1%) and brain trauma (24.7%). The overall in-hospital mortality was 17.2%. Patients with XDR A. baumannii had a prolonged hospital stay (67.8 days, P = 0.003) and time at risk (30.0 days, P = 0.0006), isolation of other MDR bacteria (75.3%, P < 0.0001). Risk factor included previous hospitalization (P < 0.0001), many kinds of invasive procedures (gastric tube, bladder catheter, intubation/tracheostomy, mechanical ventilation, suctioning/bronchoscopy, intravascular catheter, P < 0.0001), previously treated with cabapenem (P < 0.0001), b-lactam/b-lactamase combination (P < 0.0001) and fluoroquinolones (P = 0.003). Conclusion: OXA-23-producing XDR A. baumannii is clonally disseminated at a university hospital and neurosurgery plays an important role in the dissemination of XDR phenotypes. It is important to minimize invasive procedures, to restrict excessive use of antibiotics, and to avoid referral frequently, in order to prevent the spreading of XDR A. baumannii. P133 Localization of resistance genes on the multiple-drug resistance plasmids in Escherichia coli isolated from beef cattle S. Yamamoto1 *, M. Nakano1 , M. Tanaka1 , W. Kitagawa1 , T. Sone1 , K. Asano1 . 1 Graduate School of Agriculture, Hokkaido University, Sapporo, Japan E-mail address : [email protected] Introduction: Antimicrobial-resistance (AMR) bacteria are a serious global concern. AMR bacteria increase by use of antimicrobial agents in farms. The prevalence of AMR in 3,147 E. coli isolates from 291 beef cattle fecal samples collected from three regions in Japan was investigated. The rate of AMR was higher than other countries. The prevalence of resistance genes differed significantly among the regions, and the genotypes showed high similarity in each farm. We suggested that the prevalence of AMR E. coli and resistance genes might be unique in each region. Objectives: This objective is to analysis the genetic relationship of AMR derivative plasmids. We investigated localization of resistance genes on the multiple-drug resistance plasmids in the E. coli strains isolated. Methods: The total 52 E. coli isolates showing resistances to one or more antibiotic were used. The resistance genes and incompatibility
(Inc) plasmids were identified with PCR and colony hybridization. Plasmids of the size of less than 16 kb were extracted by alkaline lysis methods, and the large plasmids were separated by S1-PFGE (pulsefield gel electrophoresis). The loci of resistance genes on the plasmids were identified by southern hybridization. Results: Every strains used had keeping plasmids from 1 to 780 kbp. The isolates of multiple-drug resistance had large-size plasmid. Approximate 60% of multidrug resistance plasmids were Inc plasmids which were detected 8 types including Inc F, FIA, FIB, I1, N, P, Y and A/C plasmids which size were 50 to 150 kbp. Inc A/C plasmid was detected from only isolates of resistance to 11 agents. Many resistance genes were located on large plasmids as multiple-drug resistance plasmid. Approximate 85% of Inc plasmids harbored resistance genes. Each plasmid was showed variety pattern of resistance genes. The resistance genes in the multiple-drug resistance isolates were varieties. The isolates with resistance to 9 agents had aacC2 gene for gentamicin-resistance, but the isolates with resistance to 11 agents didn’t have this gene; the isolates with resistance to 11 agents had aac(3)-VIa gene for gentamicin-resistance. Conclusion: Plasmids in the multiple-drug resistance isolates had a variety of resistance genes. However, plasmid and resistance gene patterns were different. These results suggest that different derivative plasmids developed from similar ancestor to multipledrug resistance, and it couldn’t always become the multiple-drug resistance strain by AMR strain obtained simply AMR. Thus, these findings may prevent acquisition of AMR.
Antibiotic usage P134 Methicillin-resistant Staphylococcus aureus from patients with blood stream infections; MIC creep for glycopeptides and arbekacin Y. Hirai1 *, S. Asahata1 , Y. Ainoda1 , T. Fujita1 , T. Konishi2 , A. Goto3 , T. Kimura2 , K. Totsuka1 . 1 Department of Infectious Diseases, 2 Department of Pharmacy, 3 Laboratory of Microbiology, Tokyo Women’s Medical University, Tokyo, Japan E-mail address : [email protected] Introduction: Blood stream infection (BSI) caused by MethicillinResistant Staphylococcus aureus (MRSA) is associated with unfavorable outcome. Evidence suggests a trend towards higher vancomycin (VCM) minimum inhibitory concentrations (MICs) for MRSA, which is termed as ’MIC creep’. We evaluated MIC creep of anti-MRSA agents (VCM, teicoplanin (TEIC), arbekacin (ABK)) and correlations between MIC creep and its usage. Methods: From April 2004 to March 2012, observational data were collected retrospectively from patients with BSI caused by MRSA at the Tokyo Women’s Medical University Hospital. The MICs were measured by WalkAway 96SI (Siemens, Germany). The defined daily dose (DDD) per 1000 patient days of VCM, TEIC, and ABK were collected according to the World Health Organization guidelines. The distributions of each MIC between April 2004 and March 2008, as the former study period, and between 2008 and 2012, as the latter study period, were compared. MIC creep was defined as increased rate of MRSA stains with reduced susceptibility (VCM 2 mg/ml, TEIC 16 mg/ml, and ABK 8 mg/ml). Statistical analyses were performed by using Fisher’s exact test and Spearman’s rank correlation coefficient in appropriate. P values less than 0.01 indicated statistical significance. Results: In total, 471 patients (252 in the former and 219 in the latter study period) with BSI caused by MRSA were included in this study. The incidence of MRSA BSI per 1000 patient days ranged from 0.093 to 0.20. The DDD per 1000 patient days ranged from 4.8 to 17.1 for VCM, from 0.5 to 4.5 for TEIC, and from 0.8 to 5.1 for ABK. Among 471 strains, 17 MRSA isolates had VCM MICs 2 mg/ml (12 strains: MICs 2 mg/ml, 5 strains: MICs 4 mg/ml). Further, 7 MRSA isolates (4.8%) had TEIC MICs 4 mg/ml. None of them had TEIC MICs > 4 mg/ml. VCM MICs crept in MRSA isolates (0.39% vs 7.3%, P = 0.00006) in a setting with increasing DDD of VCM (5.0 in 2003, 17.4 in 2011). MIC creep was not observed for TEIC in a setting with decreasing DDD of TEIC (4.5 in 2005, 0.5 in 2010). Further, 13 MRSA strains with ABK MICs 8 mg/ml
Posters / International Journal of Antimicrobial Agents 42S2 (2013) S41–S159
Conclusion: Multidrug resistant K. pneumoniae isolates habouring bla OXA-48 and bla NDM has emerged in Saudi Arabia. The identification of colistin resistant isolates is of major concern. P132 Clonal dissemination of OXA-23-producing extensively drug resistant Acinetobacter baumannii at a teaching hospital Y. Li1 *, Q. Guo1 , X. Ye1 , D. Zhu1 , M. Wang1 . 1 Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China E-mail address : [email protected] Introduction: Extensively drug resistant Acinetobacter baumannii presents a serious therapeutic and infection control challenge. We describe the molecular and clinical characteristics of 106 consecutive non-duplicate extensively drug resistant (XDR) Acinetobacter baumannii at a hospital in Shanghai, China. Methods: One-hundred and six clinical isolates of XDR A. baumannii were collected from January to December 2010. Antimicrobial susceptibilities were determined by agar dilution method. The prevalence of the carbapenemase genes were investigated by polymerase chain reaction (PCR)amplification. Genetic relatedness of isolates was determined by multilocus sequence typing (MLST) and Enterobacterial repetive intergenic consensus-PCR (ERIC-PCR). A case-control study was performed from January to December 2010. Cases were defined as patients clolonized or infected by XDR A. baumannii , and controls were patients without A. baumannii isolation, in an 1:1 proportion. Results: All 106 A. baumannii isolates were resistant to all antimicrobial agents tested, except colistin and tigecycline. All isolates possessed bla OXA-51-like and bla OXA-23-like. One-hundred and five isolates belonged to clonal complex 92. According to ERIC-PCR, clone A1 and A2 were the predominant clones, comprising 75.5% of all isolates. Neurosurgical patients comprised 48.4% of all patients, especially brain surgery (44.1%) and brain trauma (24.7%). The overall in-hospital mortality was 17.2%. Patients with XDR A. baumannii had a prolonged hospital stay (67.8 days, P = 0.003) and time at risk (30.0 days, P = 0.0006), isolation of other MDR bacteria (75.3%, P < 0.0001). Risk factor included previous hospitalization (P < 0.0001), many kinds of invasive procedures (gastric tube, bladder catheter, intubation/tracheostomy, mechanical ventilation, suctioning/bronchoscopy, intravascular catheter, P < 0.0001), previously treated with cabapenem (P < 0.0001), b-lactam/b-lactamase combination (P < 0.0001) and fluoroquinolones (P = 0.003). Conclusion: OXA-23-producing XDR A. baumannii is clonally disseminated at a university hospital and neurosurgery plays an important role in the dissemination of XDR phenotypes. It is important to minimize invasive procedures, to restrict excessive use of antibiotics, and to avoid referral frequently, in order to prevent the spreading of XDR A. baumannii. P133 Localization of resistance genes on the multiple-drug resistance plasmids in Escherichia coli isolated from beef cattle S. Yamamoto1 *, M. Nakano1 , M. Tanaka1 , W. Kitagawa1 , T. Sone1 , K. Asano1 . 1 Graduate School of Agriculture, Hokkaido University, Sapporo, Japan E-mail address : [email protected] Introduction: Antimicrobial-resistance (AMR) bacteria are a serious global concern. AMR bacteria increase by use of antimicrobial agents in farms. The prevalence of AMR in 3,147 E. coli isolates from 291 beef cattle fecal samples collected from three regions in Japan was investigated. The rate of AMR was higher than other countries. The prevalence of resistance genes differed significantly among the regions, and the genotypes showed high similarity in each farm. We suggested that the prevalence of AMR E. coli and resistance genes might be unique in each region. Objectives: This objective is to analysis the genetic relationship of AMR derivative plasmids. We investigated localization of resistance genes on the multiple-drug resistance plasmids in the E. coli strains isolated. Methods: The total 52 E. coli isolates showing resistances to one or more antibiotic were used. The resistance genes and incompatibility
(Inc) plasmids were identified with PCR and colony hybridization. Plasmids of the size of less than 16 kb were extracted by alkaline lysis methods, and the large plasmids were separated by S1-PFGE (pulsefield gel electrophoresis). The loci of resistance genes on the plasmids were identified by southern hybridization. Results: Every strains used had keeping plasmids from 1 to 780 kbp. The isolates of multiple-drug resistance had large-size plasmid. Approximate 60% of multidrug resistance plasmids were Inc plasmids which were detected 8 types including Inc F, FIA, FIB, I1, N, P, Y and A/C plasmids which size were 50 to 150 kbp. Inc A/C plasmid was detected from only isolates of resistance to 11 agents. Many resistance genes were located on large plasmids as multiple-drug resistance plasmid. Approximate 85% of Inc plasmids harbored resistance genes. Each plasmid was showed variety pattern of resistance genes. The resistance genes in the multiple-drug resistance isolates were varieties. The isolates with resistance to 9 agents had aacC2 gene for gentamicin-resistance, but the isolates with resistance to 11 agents didn’t have this gene; the isolates with resistance to 11 agents had aac(3)-VIa gene for gentamicin-resistance. Conclusion: Plasmids in the multiple-drug resistance isolates had a variety of resistance genes. However, plasmid and resistance gene patterns were different. These results suggest that different derivative plasmids developed from similar ancestor to multipledrug resistance, and it couldn’t always become the multiple-drug resistance strain by AMR strain obtained simply AMR. Thus, these findings may prevent acquisition of AMR.
Antibiotic usage P134 Methicillin-resistant Staphylococcus aureus from patients with blood stream infections; MIC creep for glycopeptides and arbekacin Y. Hirai1 *, S. Asahata1 , Y. Ainoda1 , T. Fujita1 , T. Konishi2 , A. Goto3 , T. Kimura2 , K. Totsuka1 . 1 Department of Infectious Diseases, 2 Department of Pharmacy, 3 Laboratory of Microbiology, Tokyo Women’s Medical University, Tokyo, Japan E-mail address : [email protected] Introduction: Blood stream infection (BSI) caused by MethicillinResistant Staphylococcus aureus (MRSA) is associated with unfavorable outcome. Evidence suggests a trend towards higher vancomycin (VCM) minimum inhibitory concentrations (MICs) for MRSA, which is termed as ’MIC creep’. We evaluated MIC creep of anti-MRSA agents (VCM, teicoplanin (TEIC), arbekacin (ABK)) and correlations between MIC creep and its usage. Methods: From April 2004 to March 2012, observational data were collected retrospectively from patients with BSI caused by MRSA at the Tokyo Women’s Medical University Hospital. The MICs were measured by WalkAway 96SI (Siemens, Germany). The defined daily dose (DDD) per 1000 patient days of VCM, TEIC, and ABK were collected according to the World Health Organization guidelines. The distributions of each MIC between April 2004 and March 2008, as the former study period, and between 2008 and 2012, as the latter study period, were compared. MIC creep was defined as increased rate of MRSA stains with reduced susceptibility (VCM 2 mg/ml, TEIC 16 mg/ml, and ABK 8 mg/ml). Statistical analyses were performed by using Fisher’s exact test and Spearman’s rank correlation coefficient in appropriate. P values less than 0.01 indicated statistical significance. Results: In total, 471 patients (252 in the former and 219 in the latter study period) with BSI caused by MRSA were included in this study. The incidence of MRSA BSI per 1000 patient days ranged from 0.093 to 0.20. The DDD per 1000 patient days ranged from 4.8 to 17.1 for VCM, from 0.5 to 4.5 for TEIC, and from 0.8 to 5.1 for ABK. Among 471 strains, 17 MRSA isolates had VCM MICs 2 mg/ml (12 strains: MICs 2 mg/ml, 5 strains: MICs 4 mg/ml). Further, 7 MRSA isolates (4.8%) had TEIC MICs 4 mg/ml. None of them had TEIC MICs > 4 mg/ml. VCM MICs crept in MRSA isolates (0.39% vs 7.3%, P = 0.00006) in a setting with increasing DDD of VCM (5.0 in 2003, 17.4 in 2011). MIC creep was not observed for TEIC in a setting with decreasing DDD of TEIC (4.5 in 2005, 0.5 in 2010). Further, 13 MRSA strains with ABK MICs 8 mg/ml