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Lydon KA, Robertson MJ, Lipp EK. Patterns of triclosan resistance in Vibrionaceae. PeerJ 2018; 6:e5170. [PMID: 30013840 PMCID: PMC6046194 DOI: 10.7717/peerj.5170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/16/2018] [Indexed: 11/30/2022] Open
Abstract
The antimicrobial additive triclosan has been used in personal care products widely across the globe for decades. Triclosan resistance has been noted among Vibrio spp., but reports have been anecdotal and the extent of phenotypic triclosan resistance across the Vibrionaceae family has not been established. Here, triclosan resistance was determined for Vibrionaceae strains across nine distinct clades. Minimum inhibitory concentrations (MIC) were determined for 70 isolates from clinical (n = 6) and environmental sources (n = 64); only two were susceptible to triclosan. The mean MIC for all resistant Vibrionaceae was 53 µg mL-1 (range 3.1-550 µg mL-1), but was significantly different between clades (p < 0.001). The highest mean triclosan MIC was observed in the Splendidus clade (200 µg mL-1; n = 3). Triclosan mean MICs were 68.8 µg mL-1 in the Damselae clade and 45.3 µg mL-1 in the Harveyi clade. The lowest mean MIC was observed in the Cholerae clade with 14.4 µg mL-1, which was primarily represented by clinical strains. There were no significant differences in triclosan MIC among individual species or among environmental strains isolated from different locations. Overall, phenotypic triclosan resistance appears to be widespread across multiple clades of Vibrionaceae.
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Affiliation(s)
- Keri A. Lydon
- Department of Environmental Health Science, University of Georgia, Athens, GA, United States of America
| | - Megan J. Robertson
- Department of Environmental Health Science, University of Georgia, Athens, GA, United States of America
| | - Erin K. Lipp
- Department of Environmental Health Science, University of Georgia, Athens, GA, United States of America
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2
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Limitations of MIC as the sole criterion in antimicrobial drug dosage regimen design: The need for full characterization of antimicrobial pharmacodynamic profile especially for drug-resistant organisms. Vet J 2013; 198:15-8. [DOI: 10.1016/j.tvjl.2013.07.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 07/30/2013] [Indexed: 11/23/2022]
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3
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Mayrhofer S, Mair C, Kneifel W, Domig KJ. Susceptibility of bifidobacteria of animal origin to selected antimicrobial agents. CHEMOTHERAPY RESEARCH AND PRACTICE 2011; 2011:989520. [PMID: 22312561 PMCID: PMC3265246 DOI: 10.1155/2011/989520] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 01/28/2011] [Indexed: 01/05/2023]
Abstract
Strains of the genus Bifidobacterium are frequently used as probiotics, for which the absence of acquired antimicrobial resistance has become an important safety criterion. This clarifies the need for antibiotic susceptibility data for bifidobacteria. Based on a recently published standard for antimicrobial susceptibility testing of bifidobacteria with broth microdilution method, the range of susceptibility to selected antibiotics in 117 animal bifidobacterial strains was examined. Narrow unimodal MIC distributions either situated at the low-end (chloramphenicol, linezolid, and quinupristin/dalfopristin) or high-end (kanamycin, neomycin) concentration range could be detected. In contrast, the MIC distribution of trimethoprim was multimodal. Data derived from this study can be used as a basis for reviewing or verifying present microbiological breakpoints suggested by regulatory agencies to assess the safety of these micro-organisms intended for the use in probiotics.
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Affiliation(s)
- Sigrid Mayrhofer
- Department of Food Sciences and Technology, Institute of Food Sciences, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Christiane Mair
- Department of Food Sciences and Technology, Institute of Food Sciences, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Wolfgang Kneifel
- Department of Food Sciences and Technology, Institute of Food Sciences, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Konrad J. Domig
- Department of Food Sciences and Technology, Institute of Food Sciences, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
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4
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Meunier D, Jouy E, Lazizzera C, Doublet B, Kobisch M, Cloeckaert A, Madec JY. Plasmid-borne florfenicol and ceftiofur resistance encoded by the floR and blaCMY-2 genes in Escherichia coli isolates from diseased cattle in France. J Med Microbiol 2010; 59:467-471. [PMID: 20056773 DOI: 10.1099/jmm.0.016162-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study was designed to determine the genetic basis of florfenicol and ceftiofur resistance in Escherichia coli isolates recovered from French cattle. In these isolates, ceftiofur resistance was conferred by bla(CMY-2) located on three distinct conjugative plasmids on a specific DNA fragment, ISEcp1-bla(CMY-2)-blc- sugE. Two of the plasmids also carried the floR gene conferring resistance to florfenicol. The floR gene was shown to be associated with the insertion sequence ISCR2. Mobile elements appear to contribute to the mobilization of floR and bla(CMY-2) genes in E. coli. The presence of bla(CMY-2) and floR on the same plasmid highlights the potential risk for a co-selection of the bla(CMY-2) gene through the use of florfenicol in food animal production.
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Affiliation(s)
- Danièle Meunier
- Agence Française de SécuritéSanitaire des Aliments, Unité Antibiorésistance et VirulenceBactériennes, 31 avenue Tony Garnier, 69364 Lyon, France
| | - Eric Jouy
- Agence Française de SécuritéSanitaire des Aliments, Unité Mycoplasmologie - Bactériologie,BP 53, 22440 Ploufragan, France
| | - Corinne Lazizzera
- Agence Française de SécuritéSanitaire des Aliments, Unité Antibiorésistance et VirulenceBactériennes, 31 avenue Tony Garnier, 69364 Lyon, France
| | - Benoît Doublet
- INRA, UR1282 Infectiologie Animale Santé Publique,37380 Nouzilly, France
| | - Marylène Kobisch
- Agence Française de SécuritéSanitaire des Aliments, Unité Mycoplasmologie - Bactériologie,BP 53, 22440 Ploufragan, France
| | - Axel Cloeckaert
- INRA, UR1282 Infectiologie Animale Santé Publique,37380 Nouzilly, France
| | - Jean-Yves Madec
- Agence Française de SécuritéSanitaire des Aliments, Unité Antibiorésistance et VirulenceBactériennes, 31 avenue Tony Garnier, 69364 Lyon, France
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5
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Turnidge J, Paterson DL. Setting and revising antibacterial susceptibility breakpoints. Clin Microbiol Rev 2007; 20:391-408, table of contents. [PMID: 17630331 PMCID: PMC1932754 DOI: 10.1128/cmr.00047-06] [Citation(s) in RCA: 366] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clinical microbiology laboratories need to communicate results of antibacterial susceptibility testing to prescribers. Sophisticated prescribers who are knowledgeable of the pharmacokinetics and pharmacodynamics of antibacterials may desire no more information than the MIC of the drug in question. However, most prescribers require interpretation of antibacterial susceptibility testing results. Breakpoints can assist in determining if an antibacterial is potentially useful in the treatment of a bacterial infection. Breakpoints should be set prior to an antibacterial being used clinically. Breakpoint setting requires integration of knowledge of the wild-type distribution of MICs, assessment of the pharmacokinetics/pharmacodynamics of the antibacterial, and study of the clinical outcome of infections when the antibacterial is used. It is mandatory that breakpoints be reviewed when antibacterial agents have been in clinical use for some time, particularly if mechanisms of bacterial resistance to the drug have been described. In general, greater amounts of information on the pharmacokinetics and pharmacodynamics of an antibacterial are available when breakpoints need to be revised. However, the opportunity to conduct randomized clinical studies of an antibacterial declines after the drug has been released commercially. Well-designed observational clinical studies are therefore necessary in order to provide reliable data to inform those reevaluating breakpoints. Breakpoint-setting organizations may also play a role in developing phenotypic tests for detection of resistance mechanisms, as this information may complement use of the breakpoint in some circumstances.
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Affiliation(s)
- John Turnidge
- Division of Laboratory Medicine, Women's and Children's Hospital, 72 King William Rd., North Adelaide, South Australia, Australia.
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6
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Mayrhofer S, Domig KJ, Amtmann E, Van Hoek AHAM, Petersson A, Mair C, Mayer HK, Kneifel W. Antibiotic susceptibility of Bifidobacterium thermophilum and Bifidobacterium pseudolongum isolates from animal sources. J Food Prot 2007; 70:119-24. [PMID: 17265870 DOI: 10.4315/0362-028x-70.1.119] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The widespread use of antimicrobial substances has led to resistant populations of microorganisms in several ecosystems. In animal husbandry, the application of antibiotics has contributed to resistance development in pathogenic and commensal bacteria. These strains or their resistance genes can be spread along several ecological routes, including the food chain. Antibiotic resistance is important in terms of the safety of industrial strains, such as probiotics for food and feed. Bifidobacterium thermophilum and Bifidobacterium pseudolongum are known to comprise the major part of the bifidobacterial microbiota in the gut and feces of cattle and pigs. In this study, the antimicrobial susceptibility in bifidobacterial isolates of these species was investigated. Isolates from the beef and pork production chain were identified and typed to strain level, and the antimicrobial susceptibility level was tested to a set of antibiotics. Isolates with low susceptibility levels were screened by PCR for already described resistance genes. Strains atypically resistant to clindamycin, erythromycin, and tetracycline were determined. The resistance genes tet(O), tet(W), and erm(X) were detected in the bifidobacterial species that were examined.
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Affiliation(s)
- Sigrid Mayrhofer
- BOKU-University of Natural Resources and Applied Life Sciences, Department of Food Science and Technology, Division of Food Microbiology and Hygiene, Gregor Mendel Strafle 33, A-1180 Vienna, Austria
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Smith EM, Green LE, Medley GF, Bird HE, Fox LK, Schukken YH, Kruze JV, Bradley AJ, Zadoks RN, Dowson CG. Multilocus sequence typing of intercontinental bovine Staphylococcus aureus isolates. J Clin Microbiol 2005; 43:4737-43. [PMID: 16145135 PMCID: PMC1234155 DOI: 10.1128/jcm.43.9.4737-4743.2005] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2004] [Revised: 03/13/2005] [Accepted: 04/17/2005] [Indexed: 11/20/2022] Open
Abstract
A total of 258 bovine-associated Staphylococcus aureus isolates from the United States, Chile, and the United Kingdom, plus the reference isolate S. aureus Newbould 305 (NCIMB 702892), were analyzed by multilocus sequence typing (MLST). A collection of previously characterized United Kingdom isolates were also included in the analysis. The results demonstrated that MLST is suitable for the differentiation of bovine S. aureus isolates from various sites (milk, teat skin, milking machine unit liners, hands, and bedding) and countries. The theory of the host specificity of S. aureus is supported by the detection of a previously undescribed clonal complex that comprised 87.4% of the isolates studied, with representatives from all geographic locations investigated. This suggests that a single clonal group has achieved a widespread distribution and is responsible for the majority of infections. Some sequence types (STs; ST25, ST115, ST124, and ST126) demonstrated site specificity, as they were significantly (P < 0.05) associated with milk or teat skin.
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Affiliation(s)
- E M Smith
- Department of Biological Sciences, University of Warwick, Coventry, UK
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8
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Smith EM, Green LE, Medley GF, Bird HE, Dowson CG. Multilocus sequence typing of Staphylococcus aureus isolated from high-somatic-cell-count cows and the environment of an organic dairy farm in the United Kingdom. J Clin Microbiol 2005; 43:4731-6. [PMID: 16145134 PMCID: PMC1234152 DOI: 10.1128/jcm.43.9.4731-4736.2005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2004] [Revised: 04/15/2005] [Accepted: 05/30/2005] [Indexed: 11/20/2022] Open
Abstract
An outbreak of Staphylococcus aureus intramammary infections on an organic dairy farm was monitored for 10 months. Environmental and milk samples were collected from a total of 26 cows and a group of 21 purchased heifers about to be introduced into the milking herd. There was variation in the rate of isolation of S. aureus (9.5 to 43.8%) from individual mammary quarters, although no S. aureus isolates were detected in the milk samples collected from the heifers. One hundred ninety-one S. aureus isolates were detected from cow milk samples (n = 182), milking machine clusters (n = 4), farm personnel (n = 4), and the environment (n = 1). Multilocus sequence typing (MLST) had a typeability of 100% when it was applied to the 191 isolates. Among the 191 isolates there was limited strain diversity, with seven sequence types (STs) dominated by two strains with closely related STs that differed at a single locus. Within individual mammary quarters there were naturally occurring dual infections, although this was identified in only 0.4% of milk samples. Different strains were associated with variable persistence within quarters. MLST is clearly a very suitable tool for the differentiation and analysis of S. aureus populations detected on dairy cattle farms.
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Affiliation(s)
- E M Smith
- Department of Biological Sciences, University of Warwick, Coventry, UK
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Soussy CJ, Nguyen J, Goldstein F, Dabernat H, Andremont A, Leclercq R, Drugeon H, Cavallo P, Chardon H, Etienne J, Rio Y, Courvalin P. In vitro antibacterial activity of moxifloxacin against hospital isolates: a multicentre study. Clin Microbiol Infect 2004; 9:997-1005. [PMID: 14616741 DOI: 10.1046/j.1469-0691.2003.00696.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the in vitro antibacterial activity of moxifloxacinin in comparison to that of other fluoroquinolones (ciprofloxacin, ofloxacin and trovafloxacin). METHODS A total of 2,196 strains was collected in 11 French hospitals in 1998. Minimum inhibitory concentrations (MICs) (mg/L) were determined by agar dilution and agar diffusion was performed with 5-microg discs. Internal quality control was carried out with genetically defined strains. RESULTS MIC50s and MIC90s of moxifloxacin against nalidixic acid (NAL)-susceptible Enterobacteriaceae (n = 663) were 0.12 and 0.5. As for other quinolones, the activity of moxifloxacin (4-32) was reduced against NAL-intermediate and NAL-resistant strains (n = 222). MIC50s and MIC90s of moxifloxacin were 2 and 4 for ciprofloxacin-susceptible P. aeruginosa (n = 128); moxifloxacin had no activity against ciprofloxacin-resistant strains (n = 56). The activity of moxifloxacin was maintained against NAL-susceptible A. baumannii (n = 11; 0.032-0.125), but reduced against NAL-resistant strains (n = 30; 16-32). H. influenzae (n = 97) and M. catarrhalis (n = 40) were inhibited by low concentrations (0.03-0.06 and 0.06-0.25, respectively). Moxifloxacin had better activity (0.06-0.12) than other tested quinolones against methicillin-susceptible S. aureus strains (n = 110); ciprofloxacin-resistant strains (n = 85) (2-8) were usually methicillin-resistant. Moxifloxacin was moderately active against enterococci (n = 149) (E. faecalis: 0.5-16; E. faecium: 2-4). Streptococci (n = 194) and pneumococci (n = 136), including 70 penicillin G-intermediate or G-resistant strains, were inhibited by low concentrations (0.25-0.5 for each species). Based on the regression curve, tentative zone diameter breakpoints could be > or =21 and <18 mm for MIC breakpoints of < or =1 and >2 mg/L, respectively. CONCLUSIONS While retaining activity against Enterobacteriaceae, moxifloxacin was moderately active against P. aeruginosa. Its activity was inferior to that of ciprofloxacin for these species. This study confirmed the comparatively high in vitro activity of moxifloxacin against Gram-positive cocci and other pathogens isolated from community-acquired respiratory tract infections.
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Affiliation(s)
- C-J Soussy
- Service de Bactériologie-Virologie-Hygiène, Henri Mondor University Hospital 94010 Creteil cedex, France.
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10
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Guérin-Faublée V, Carret G, Houffschmitt P. In vitro activity of 10 antimicrobial agents against bacteria isolated from cows with clinical mastitis. Vet Rec 2003; 152:466-71. [PMID: 12723630 DOI: 10.1136/vr.152.15.466] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The susceptibility of 495 strains of bacteria, recently isolated in France from cows with clinical mastitis, to 10 antimicrobial agents--penicillin G, cloxacillin, oxacillin, cephalexin, cefazolin, cephapirin, cefquinome, neomycin, ampicillin and colistin--was determined by measuring their minimum inhibitory concentrations (MICS). Overall, the levels of resistance were very low except for staphylococci and penicillin G. The 167 streptococcal strains were susceptible to all of the beta-lactams tested, but six (3-6 per cent) were highly resistant to neomycin. Of the 171 staphylococcal isolates, 36.2 per cent were resistant to penicillin G, one strain of Staphylococcus sciuri was classified as methicillin-resistant, but they were all susceptible to neomycin. None of the 122 strains of Escherichia coli was resistant to colistin, but 12 had high MIC values for one or more of the cephalosporins.
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Affiliation(s)
- V Guérin-Faublée
- Département de Santé Publique Veterinaire, Ecole Nationale Véterinaire de Lyon, BP 83, 69280 Marcy l'étoile, France
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Mihaila-Amrouche L, Schlegel L, Collobert G, Bouvet A. Évolution de la sensibilité aux antibiotiques des souches de Streptocoques et Entérocoques responsables d'endocardites infectieuses en France de 1990 à 1999. Med Mal Infect 2002. [DOI: 10.1016/s0399-077x(02)00425-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Cotter G, Adley CC. Comparison and evaluation of antimicrobial susceptibility testing of enterococci performed in accordance with six national committee standardized disk diffusion procedures. J Clin Microbiol 2001; 39:3753-6. [PMID: 11574610 PMCID: PMC88426 DOI: 10.1128/jcm.39.10.3753-3756.2001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Studies were conducted to compare and evaluate antimicrobial susceptibility test results for enterococci obtained by six national committee disk diffusion procedures. Variations in the incidence of isolates in resistance categories and errors were associated with the use of ciprofloxacin, gentamicin, nitrofurantoin, rifampin, and teicoplanin in a number of committee procedures. Results indicate that laboratories performing disk diffusion antimicrobial susceptibility testing may have problems correctly identifying resistance in enterococci with agents used to combat infections and that it may be difficult to compare resistance data for surveillance purposes.
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Affiliation(s)
- G Cotter
- Microbiology Laboratory, Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland
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13
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Chastagner P, Plouvier E, Eyer D, Plesiat P, Lozniewski A, Sommelet D. Efficacy of cefepime and amikacin in the empiric treatment of febrile neutropenic children with cancer. MEDICAL AND PEDIATRIC ONCOLOGY 2000; 34:306-8. [PMID: 10742081 DOI: 10.1002/(sici)1096-911x(200004)34:4<306::aid-mpo24>3.0.co;2-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- P Chastagner
- Pediatric Oncology Department, CHU Nancy, Nancy, France.
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14
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Ziha-Zarifi I, Llanes C, Köhler T, Pechere JC, Plesiat P. In vivo emergence of multidrug-resistant mutants of Pseudomonas aeruginosa overexpressing the active efflux system MexA-MexB-OprM. Antimicrob Agents Chemother 1999; 43:287-91. [PMID: 9925520 PMCID: PMC89065 DOI: 10.1128/aac.43.2.287] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During a 6-month period, 21 pairs of Pseudomonas aeruginosa isolates susceptible (pretherapy) and resistant (posttherapy) to antipseudomonal beta-lactam antibiotics were isolated from hospitalized patients. In vivo emergence of beta-lactam resistance was associated with the overexpression of AmpC beta-lactamase in 10 patients. In the other 11 patients, the posttherapy isolates produced only low, basal levels of beta-lactamase and had increased levels of resistance to a variety of non-beta-lactam antibiotics (e.g., quinolones, tetracyclines, and trimethoprim) compared with the levels of beta-lactamase production and resistance of their pretherapy counterparts. These data suggested the involvement of the MexA-MexB-OprM active efflux system in the multidrug resistance phenotype of the posttherapy strains. Immunoblotting of the outer membrane proteins of these 11 bacterial pairs with a specific polyclonal antibody raised against OprM demonstrated the overexpression of OprM in all the posttherapy isolates. To determine whether mutations in mexR, the regulator gene of the mexA-mexB-oprM efflux operon, could account for the overproduction of the efflux system, sequencing experiments were carried out with the 11 bacterial pairs. Eight posttherapy isolates were found to contain insertions or deletions that led to frameshifts in the coding sequences of mexR. Two resistant strains had point mutations in mexR that yielded single amino acid changes in the protein MexR, while another strain did not show any mutation in mexR or in the promoter region upstream of mexR. Introduction of a plasmid-encoded wild-type mexR gene into five posttherapy isolates partially restored the susceptibility of the bacteria to selected antibiotics. These results indicate that in the course of antimicrobial therapy multidrug-resistant active efflux mutants overexpressing the MexA-MexB-OprM system may emerge as a result of mutations in the mexR gene.
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Affiliation(s)
- I Ziha-Zarifi
- Laboratoire de Bactériologie, Hôpital Jean Minjoz, Besançon, France
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