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Virulence factor profiles and genetic background of quinolone-resistant Escherichia coli isolated from hospital effluent
Abstracts / International Journal of Infectious Diseases 53S (2016) 4–163
Plasmid-encoded colistin resistance mediated by the mobile colistin resistance-1 (mcr-1) gene has been identified in food animal, human, food, and environmental isolates on every continent. We report on results of a screening survey on colistin-resistant E. coli in retail broiler meat and poultry caecal samples collected in Austria in 2016. Methods & Materials: A total of 164 caecal samples from poultry (110 broilers, 54 turkeys) and 115 meat samples from broilers were collected at slaughterhouses and at retail outlets in the framework of an EU surveillance programme on antimicrobial resistance between February and June 2016 in Austria. Samples were screened for the presence of colistin-resistant E. coli using non-selective enrichment broth and MacConkey agar supplemented with 0.2 to 0.6 mg/L colistin. Antimicrobial susceptibility was determined by Sensititre microbroth dilution using EUVSEC and EUVSEC2 plates. Colistin-resistant isolates were sequenced using the Illumina MiSeq platform. The assembled genomes were analyzed with pipelines MLST, PlasmidFinder, and ResFinder available from the Center for Genomic Epidemiology. PCR amplification was performed to identify plasmid-encoded AmpC genes. Results: Two colistin-resistant E. coli strains were isolated from broiler meat, one of domestic and one of Italian origin. Two additional isolates were found in caecal samples from broilers and turkeys, respectively. All isolates except the one from turkey carried the mcr-1 gene. The mcr-1-positive isolates belonged to different MLST sequence types (ST-10, ST-616, ST-43) and showed a MIC value of 4 to 8 mg/L for colistin. The isolates harboured multiple plasmid replicons with IncFIC(FII), IncFIB(AP001918) and IncX4 being present in all of them. Besides mcr-1, the isolates contained up to seven additional resistance genes including blaTEM-1B which was detected in all strains. The isolates were found to be negative for ESBLs, plasmid-mediated AmpC, and carbapenemases. Conclusion: Using selective screening for colistin-resistant bacteria, 0.9% of caecal samples and 1.7% of meat samples from broilers were shown to be positive for E. coli carrying mcr-1. The study is the first documentation of plasmid-mediated colistin resistance in E. coli isolated from poultry and poultry meat in Austria. http://dx.doi.org/10.1016/j.ijid.2016.11.099 19.005 Virulence factor profiles and genetic background of quinolone-resistant Escherichia coli isolated from hospital effluent L. Anssour ∗ , Y. Messai, R. Bakour university of sciences and technology, houari boumediene, cellular and molecular biology, Algiers/DZ Purpose: The widespread species Escherichia coli includes a broad variety of different types, ranging from highly pathogenic strains causing worldwide outbreaks of severe disease to avirulent isolates which are part of the normal intestinal flora. Pathogenicity is mainly determined by specific virulence factors which include adhesins, invasins, toxins and capsule. Several studies on clinical E. coli have demonstrated relationship between antibiotic resistance and low prevalence of virulence factors and suggested that quinolone resistance may be directly associated with the loss of virulence. The objective of this study was to evaluate the potential virulence of quinolone-resistant E. coli strains recovered from wastewater hospital. Methods & Materials: 24 isolates of E. coli were selected on Tergitol-7 agar supplemented with ciprofloxacin (2 mg/L) and identified by API 20E system. These strains were screened by PCR for 20
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virulence genes: papA, sfa/foc, afa/dra, fimH, kpsMII, entB, irp2, iutA, iroN, hlyF, iss, ompT, traT, eae, bfp, aggR, LT, ST, stx, and ibeA. Phylogenetics groups and sequence-types were determined by PCR and sequencing. The clonal relationship between isolates was investigated by ERIC-PCR. Results: Virulence genes detected were: fimH (n= 24, 100%), entB (n= 24, 100%), traT (n= 20, 83,3%), hlyF (n= 17, 70,8%), ompT (n= 16, 66,6%), iss (n= 10, 41,6%), iroN (n= 10, 41,6%), irp2 (n= 7, 29,1%), and iutA (n= 6, 25%). The combination of virulence factors allowed to distinguish eight virulence profiles, of which five were predictive of APEC pathotype, they include iss, ompT, iroN, iutA and hlyF genes. Phylogenetic groups A, B1 and D and sequence types ST405, ST443, ST101, ST10 and ST347 were identified in these isolates. ERIC-PCR molecular typing of isolates showed 12 different genetic profiles. Conclusion: This study highlighted the possible association between quinolone resistance and certain virulence factors and the potential role of hospital effluents in the dissemination of virulence genes in natural environments. http://dx.doi.org/10.1016/j.ijid.2016.11.100 19.007 Antibiotic susceptibility and -lactamase production of Gram-negative bacteria from swimming pools in Slovenia B. Bedenic a,∗ , M. Siroglavic b , N. Beader a , K. Godic-Torkar c , I. Marekovic d a
School of Medicine, University of Zagreb, Clinical Deprtment for Clinical and Molecular Microbiology, Zagreb/HR b University Hospital Center Zagreb, Transfusiology, Zagreb/HR c Faculty of Health Sciences, Sanitary Department, Ljubljana/SI d School of Medicine, University of Zagreb, University Hospital Center Zagreb, Clinical Department for Clinical and Molecular Microbiology, Zagreb/HR Purpose: -lactamases are enzymes which hydrolyze -lactam antibiotics. The first -lactamases were reported before the lactams were introduced into the clinical practice, mostly from environmental bacteria. Therefore, it is likely to expect that there is a pool of -lactamase encoding genes in the environment. Gram-negative bacteria are ubiquitous in nature and are widely distributed in soil and water. Extended-spectrum -lactamases (ESBLs) hydrolyze penicillins, cephalosporins of the 1st, 2nd, 3rd and 4th generation and monobactams. Carbapenemases hydrolyze carbapenems and belong to class A, B (metallo--lactamases or MBLs) and D (carbapenem-hydrolyzing oxacillinases). The aim of the study was to analyze antibiotic susceptibility and -lactamase production of Gram-negative isolates collected from the swiming pools in Slovenia. Methods & Materials: The collection included 10 Pseudomonas aeruginosa strains, 1 Pseudomonas putida, one Serratia marcescens, 1 Citrobacter farmeri, one Citrobacter brackii, one Citrobacter koseri, one Klebsiella oxytoca, one Escherichia coli, three Acinetobacter baumannii and one Cryseobacterium spp. In total 21 Gram-negative strains were collected from various swimming pools in Slovenia. The antimicrobial susceptibilty was determined by disk-diffusion and broth microdilution method according to CLSI. Production of ESBLs was detected by doubledisk synergy test (DDST) and combined disk test with clavulanic acid. MBLs were detected by combined disk test with EDTA. Resistance genes including those encoding ESBLs (blaTEM , blaSHV ,
Plasmid-encoded colistin resistance mediated by the mobile colistin resistance-1 (mcr-1) gene has been identified in food animal, human, food, and environmental isolates on every continent. We report on results of a screening survey on colistin-resistant E. coli in retail broiler meat and poultry caecal samples collected in Austria in 2016. Methods & Materials: A total of 164 caecal samples from poultry (110 broilers, 54 turkeys) and 115 meat samples from broilers were collected at slaughterhouses and at retail outlets in the framework of an EU surveillance programme on antimicrobial resistance between February and June 2016 in Austria. Samples were screened for the presence of colistin-resistant E. coli using non-selective enrichment broth and MacConkey agar supplemented with 0.2 to 0.6 mg/L colistin. Antimicrobial susceptibility was determined by Sensititre microbroth dilution using EUVSEC and EUVSEC2 plates. Colistin-resistant isolates were sequenced using the Illumina MiSeq platform. The assembled genomes were analyzed with pipelines MLST, PlasmidFinder, and ResFinder available from the Center for Genomic Epidemiology. PCR amplification was performed to identify plasmid-encoded AmpC genes. Results: Two colistin-resistant E. coli strains were isolated from broiler meat, one of domestic and one of Italian origin. Two additional isolates were found in caecal samples from broilers and turkeys, respectively. All isolates except the one from turkey carried the mcr-1 gene. The mcr-1-positive isolates belonged to different MLST sequence types (ST-10, ST-616, ST-43) and showed a MIC value of 4 to 8 mg/L for colistin. The isolates harboured multiple plasmid replicons with IncFIC(FII), IncFIB(AP001918) and IncX4 being present in all of them. Besides mcr-1, the isolates contained up to seven additional resistance genes including blaTEM-1B which was detected in all strains. The isolates were found to be negative for ESBLs, plasmid-mediated AmpC, and carbapenemases. Conclusion: Using selective screening for colistin-resistant bacteria, 0.9% of caecal samples and 1.7% of meat samples from broilers were shown to be positive for E. coli carrying mcr-1. The study is the first documentation of plasmid-mediated colistin resistance in E. coli isolated from poultry and poultry meat in Austria. http://dx.doi.org/10.1016/j.ijid.2016.11.099 19.005 Virulence factor profiles and genetic background of quinolone-resistant Escherichia coli isolated from hospital effluent L. Anssour ∗ , Y. Messai, R. Bakour university of sciences and technology, houari boumediene, cellular and molecular biology, Algiers/DZ Purpose: The widespread species Escherichia coli includes a broad variety of different types, ranging from highly pathogenic strains causing worldwide outbreaks of severe disease to avirulent isolates which are part of the normal intestinal flora. Pathogenicity is mainly determined by specific virulence factors which include adhesins, invasins, toxins and capsule. Several studies on clinical E. coli have demonstrated relationship between antibiotic resistance and low prevalence of virulence factors and suggested that quinolone resistance may be directly associated with the loss of virulence. The objective of this study was to evaluate the potential virulence of quinolone-resistant E. coli strains recovered from wastewater hospital. Methods & Materials: 24 isolates of E. coli were selected on Tergitol-7 agar supplemented with ciprofloxacin (2 mg/L) and identified by API 20E system. These strains were screened by PCR for 20
37
virulence genes: papA, sfa/foc, afa/dra, fimH, kpsMII, entB, irp2, iutA, iroN, hlyF, iss, ompT, traT, eae, bfp, aggR, LT, ST, stx, and ibeA. Phylogenetics groups and sequence-types were determined by PCR and sequencing. The clonal relationship between isolates was investigated by ERIC-PCR. Results: Virulence genes detected were: fimH (n= 24, 100%), entB (n= 24, 100%), traT (n= 20, 83,3%), hlyF (n= 17, 70,8%), ompT (n= 16, 66,6%), iss (n= 10, 41,6%), iroN (n= 10, 41,6%), irp2 (n= 7, 29,1%), and iutA (n= 6, 25%). The combination of virulence factors allowed to distinguish eight virulence profiles, of which five were predictive of APEC pathotype, they include iss, ompT, iroN, iutA and hlyF genes. Phylogenetic groups A, B1 and D and sequence types ST405, ST443, ST101, ST10 and ST347 were identified in these isolates. ERIC-PCR molecular typing of isolates showed 12 different genetic profiles. Conclusion: This study highlighted the possible association between quinolone resistance and certain virulence factors and the potential role of hospital effluents in the dissemination of virulence genes in natural environments. http://dx.doi.org/10.1016/j.ijid.2016.11.100 19.007 Antibiotic susceptibility and -lactamase production of Gram-negative bacteria from swimming pools in Slovenia B. Bedenic a,∗ , M. Siroglavic b , N. Beader a , K. Godic-Torkar c , I. Marekovic d a
School of Medicine, University of Zagreb, Clinical Deprtment for Clinical and Molecular Microbiology, Zagreb/HR b University Hospital Center Zagreb, Transfusiology, Zagreb/HR c Faculty of Health Sciences, Sanitary Department, Ljubljana/SI d School of Medicine, University of Zagreb, University Hospital Center Zagreb, Clinical Department for Clinical and Molecular Microbiology, Zagreb/HR Purpose: -lactamases are enzymes which hydrolyze -lactam antibiotics. The first -lactamases were reported before the lactams were introduced into the clinical practice, mostly from environmental bacteria. Therefore, it is likely to expect that there is a pool of -lactamase encoding genes in the environment. Gram-negative bacteria are ubiquitous in nature and are widely distributed in soil and water. Extended-spectrum -lactamases (ESBLs) hydrolyze penicillins, cephalosporins of the 1st, 2nd, 3rd and 4th generation and monobactams. Carbapenemases hydrolyze carbapenems and belong to class A, B (metallo--lactamases or MBLs) and D (carbapenem-hydrolyzing oxacillinases). The aim of the study was to analyze antibiotic susceptibility and -lactamase production of Gram-negative isolates collected from the swiming pools in Slovenia. Methods & Materials: The collection included 10 Pseudomonas aeruginosa strains, 1 Pseudomonas putida, one Serratia marcescens, 1 Citrobacter farmeri, one Citrobacter brackii, one Citrobacter koseri, one Klebsiella oxytoca, one Escherichia coli, three Acinetobacter baumannii and one Cryseobacterium spp. In total 21 Gram-negative strains were collected from various swimming pools in Slovenia. The antimicrobial susceptibilty was determined by disk-diffusion and broth microdilution method according to CLSI. Production of ESBLs was detected by doubledisk synergy test (DDST) and combined disk test with clavulanic acid. MBLs were detected by combined disk test with EDTA. Resistance genes including those encoding ESBLs (blaTEM , blaSHV ,