1
|
Stubberfield E, AbuOun M, Card RM, Welchman D, Anjum MF. Molecular characterization of antimicrobial resistance in Brachyspira species isolated from UK chickens: Identification of novel variants of pleuromutilin and beta-lactam resistance genes. Vet Microbiol 2024; 290:109992. [PMID: 38306769 DOI: 10.1016/j.vetmic.2024.109992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 12/21/2023] [Accepted: 01/10/2024] [Indexed: 02/04/2024]
Abstract
Brachyspira species are Gram negative, anaerobic bacteria that colonise the gut of many animals, including poultry. In poultry, Brachyspira species can be commensal (B. innocens, B. murdochii, 'B. pulli') or pathogenic (B. pilosicoli, B. intermedia, B. alvinipulli or rarely B. hyodysenteriae), the latter causing avian intestinal spirochaetosis (AIS). Antimicrobial therapy options for treatment is limited, frequently involving administration of the pleuromutilin, tiamulin, in water. In this study 38 Brachyspira isolates from chickens in the UK, representing both commensal and pathogenic species, were whole genome sequenced to identify antimicrobial resistance (AMR) mechanisms and the minimum inhibitory concentration (MIC) to a number of antimicrobials was also determined. We identified several new variants of blaOXA in B. pilosicoli and B. pulli isolates, and variations in tva which led to two new tva variants in B.murdochii and B.pulli. A number of isolates also harboured mutations known to encode AMR in the 16S and 23S rRNA genes. The percentage of isolates that were genotypically multi-drug resistance (MDR) was 16%, with the most common resistance profile being: tetracycline, pleuromutilin and beta-lactam, which were found in three 'B. pulli' and one B. pilosicoli. There was good correlation with the genotype and the corresponding antibiotic MIC phenotypes: pleuromutilins (tiamulin and valnemulin), macrolides (tylosin and tylvalosin), lincomycin and doxycycline. The occurrence of resistance determinants identified in this study in pathogenic Brachyspira, especially those which were MDR, is likely to impact treatment of AIS and clearance of infections on farm.
Collapse
Affiliation(s)
- Emma Stubberfield
- Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Manal AbuOun
- Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
| | - Roderick M Card
- Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - David Welchman
- Animal and Plant Health Agency Winchester, Itchen Abbas, Winchester SO21 1BX, UK
| | - Muna F Anjum
- Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| |
Collapse
|
2
|
Hakimi M, Ye F, Stinman CC, Sahin O, Burrough ER. Antimicrobial susceptibility of U.S. porcine Brachyspira isolates and genetic diversity of B. hyodysenteriae by multilocus sequence typing. J Vet Diagn Invest 2024; 36:62-69. [PMID: 37968893 PMCID: PMC10734594 DOI: 10.1177/10406387231212189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023] Open
Abstract
Swine dysentery, caused by Brachyspira hyodysenteriae and the newly recognized Brachyspira hampsonii in grower-finisher pigs, is a substantial economic burden in many swine-rearing countries. Antimicrobial therapy is the only commercially available measure to control and prevent Brachyspira-related colitis. However, data on antimicrobial susceptibility trends and genetic diversity of Brachyspira species from North America is limited. We evaluated the antimicrobial susceptibility profiles of U.S. Brachyspira isolates recovered between 2013 and 2022 to tiamulin, tylvalosin, lincomycin, doxycycline, bacitracin, and tylosin. In addition, we performed multilocus sequence typing (MLST) on 64 B. hyodysenteriae isolates. Overall, no distinct alterations in the susceptibility patterns over time were observed among Brachyspira species. However, resistance to the commonly used antimicrobials was seen sporadically with a higher resistance frequency to tylosin compared to other tested drugs. B. hampsonii was more susceptible to the tested drugs than B. hyodysenteriae and B. pilosicoli. MLST revealed 16 different sequence types (STs) among the 64 B. hyodysenteriae isolates tested, of which 5 STs were previously known, whereas 11 were novel. Most isolates belonged to the known STs: ST93 (n = 32) and ST107 (n = 13). Our findings indicate an overall low prevalence of resistance to clinically important antimicrobials other than tylosin and bacitracin, and high genetic diversity among the clinical Brachyspira isolates from pigs in the United States during the past decade. Further molecular, epidemiologic, and surveillance studies are needed to better understand the infection dynamics of Brachyspira on swine farms and to help develop effective control measures.
Collapse
Affiliation(s)
- Maria Hakimi
- Departments of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
| | - Fangshu Ye
- Statistics, Iowa State University, Ames, IA, USA
| | - Chloe C. Stinman
- Veterinary Diagnostic Laboratory, Iowa State University, Ames, IA, USA
| | - Orhan Sahin
- Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
| | - Eric R. Burrough
- Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
| |
Collapse
|
3
|
Predictive Power of Long-Read Whole-Genome Sequencing for Rapid Diagnostics of Multidrug-Resistant Brachyspira hyodysenteriae Strains. Microbiol Spectr 2023; 11:e0412322. [PMID: 36602320 PMCID: PMC9927316 DOI: 10.1128/spectrum.04123-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Infections with Brachyspira hyodysenteriae, the etiological agent of swine dysentery, result in major economic losses in the pig industry worldwide. Even though microbial differentiation of various Brachyspira species can be obtained via PCR, no quick diagnostics for antimicrobial susceptibility testing are in place, which is mainly due to the time-consuming (4 to 7 days) anaerobic growth requirements of these organisms. Veterinarians often rely on a clinical diagnosis for initiating antimicrobial treatment. These treatments are not always effective, which may be due to high levels of acquired resistance in B. hyodysenteriae field isolates. By using long-read-only whole-genome sequencing and a custom-trained Bonito base-calling model, 81 complete B. hyodysenteriae genomes with median Q51 scores and 99% completeness were obtained from 86 field strains. This allowed the assessment of the predictive potential of genetic markers in relation to the observed acquired resistance phenotypes obtained via agar dilution susceptibility testing. Multidrug resistance was observed in 77% and 21% of the tested strains based on epidemiological cutoff and clinical breakpoint values, respectively. The predictive power of genetic hallmarks (genes and/or gene mutations) for antimicrobial susceptibility testing was promising. Sensitivity and specificity for tiamulin [tva(A) and 50SL3N148S, 99% and 67%], valnemulin [tva(A), 97% and 92%), lincomycin (23SA2153T/G and lnuC, 94% and 100%), tylvalosin (23SA2153T/G, 99% and 93%), and doxycycline (16SG1026C, 93% and 87%) were determined. The predictive power of these genetic hallmarks is promising for use in sequencing-based workflows to speed up swine dysentery diagnostics in veterinary medicine and determine proper antimicrobial use. IMPORTANCE Diagnostics for swine dysentery rely on the identification of Brachyspira species using molecular techniques. Nevertheless, no quick diagnostic tools are available for antimicrobial susceptibility testing due to extended growth requirements (7 to 14 days). To enable practitioners to tailor antimicrobial treatment to specific strains, long-read sequencing-based methods are expected to lead to rapid methods in the future. Nevertheless, their potential implementation should be validated extensively. This mainly implies assessing sequencing accuracy and the predictive power of genetic hallmarks in relation to their observed (multi)resistance phenotypes.
Collapse
|
4
|
Vega C, Pérez-Pérez L, Argüello H, Gómez-García M, Puente H, Fernández-Usón I, Rubio P, Carvajal A. In vitro evaluation of gentamicin activity against Spanish field isolates of Brachyspira hyodysenteriae. Porcine Health Manag 2022; 8:48. [DOI: 10.1186/s40813-022-00291-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/14/2022] [Indexed: 12/02/2022] Open
Abstract
Abstract
Background
The treatment of swine dysentery (SD) has become constrained in recent years due to the limited availability of effective drugs combined with a rise in antimicrobial resistance. Gentamicin, an aminoglycoside antibiotic, is authorised for the control of this disease in several European countries but has not been extensively used so far. In this study, the in vitro susceptibility of 56 Brachyspira hyodysenteriae field isolates was evaluated against gentamicin using a broth microdilution test. The molecular basis of decreased susceptibility to gentamicin was also investigated by sequencing the 16S rRNA gene and phylogenetic relatedness by multiple-locus variable number tandem-repeat analysis (MLVA).
Results
Most B. hyodysenteriae isolates presented low minimum inhibitory concentration (MIC) values to gentamicin, with a mode of 2 µg/mL, a median or MIC50 of 4 µg/mL and percentile 90 or MIC90 of 16 µg/mL. The distribution of these values over the period studied (2011–2019) did not show a tendency towards the development of resistance to gentamicin. Differences in susceptibility among isolates could be explained by two point-mutations in the 16S rRNA gene, C990T and A1185G, which were only present in isolates with high MICs. These isolates were typed in three different MLVA clusters. Analyses of co-resistance between gentamicin and antimicrobials commonly used for the treatment of SD revealed that resistance to tiamulin and valnemulin was associated with low MICs for gentamicin.
Conclusions
The results provide an accurate characterisation of antimicrobial sensitivity to gentamicin and possible mechanisms of resistance in Spanish B. hyodysenteriae isolates. These findings allow us to propose gentamicin as an alternative in the antibiotic management of SD, particularly in outbreaks caused by pleuromutilin resistant isolates.
Collapse
|
5
|
Tylvalosin demonstrates anti-parasitic activity and protects mice from acute toxoplasmosis. Life Sci 2022; 294:120373. [DOI: 10.1016/j.lfs.2022.120373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 01/28/2022] [Accepted: 01/29/2022] [Indexed: 11/19/2022]
|
6
|
Dual Antimicrobial Effect of Medium-Chain Fatty Acids against an Italian Multidrug Resistant Brachyspira hyodysenteriae Strain. Microorganisms 2022; 10:microorganisms10020301. [PMID: 35208756 PMCID: PMC8875639 DOI: 10.3390/microorganisms10020301] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/05/2022] [Accepted: 01/24/2022] [Indexed: 01/27/2023] Open
Abstract
The fastidious nature of Brachyspira hyodysenteriae limits an accurate in vitro pre-screening of conventionally used antibiotics and other candidate alternative antimicrobials. This results in a non-judicious use of antibiotics, leading to an exponential increase of the antibiotic resistance issue and a slowdown in the research for new molecules that might stop this serious phenomenon. In this study we tested four antibiotics (tylosin, lincomycin, doxycycline, and tiamulin) and medium-chain fatty acids (MCFA; hexanoic, octanoic, decanoic, and dodecanoic acid) against an Italian field strain of B. hyodysenteriae and the ATCC 27164 strain as reference. We determined the minimal inhibitory concentrations of these substances, underlining the multidrug resistance pattern of the field strain and, on the contrary, a consistent and stable inhibitory effect of the tested MCFA against both strains. Then, sub-inhibitory concentrations of antibiotics and MCFA were examined in modulating a panel of B. hyodysenteriae virulence genes (tlyA, tlyB, bhlp16, bhlp29.7, and bhmp39f). Results of gene expression analysis were variable, with up- and downregulations not properly correlated with particular substances or target genes. Decanoic and dodecanoic acid with their direct and indirect antimicrobial property were the most effective among MCFA, suggesting them as good candidates for subsequent in vivo trials.
Collapse
|
7
|
Gómez-García M, Argüello H, Pérez-Pérez L, Vega C, Puente H, Mencía-Ares Ó, Rubio P, Carvajal A. Combined in-vitro and on-farm evaluation of commercial disinfectants used against Brachyspira hyodysenteriae. Porcine Health Manag 2022; 8:3. [PMID: 34998431 PMCID: PMC8742949 DOI: 10.1186/s40813-021-00244-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/16/2021] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Swine dysentery (SD) is a severe infectious disease with a relevant impact on pig production usually caused by Brachyspira hyodysenteriae, although B. hampsonii causes an identical clinical picture. SD control relies on antimicrobials, good management practices and strict biosecurity with cleaning and disinfection as crucial tools to avoid the pathogen transmission. This study evaluates the in-vitro efficacy of an array of commercial disinfectants against a collection of B. hyodysenteriae isolates using broth tests. The efficacy of cleaning and disinfection protocols was also evaluated on two farms with endemic SD using surface swabs collected in emptied pens before and after cleaning and disinfection procedures, using both real-time PCR and bacterial microbiological culture. RESULTS Most of the commercial disinfectants evaluated were effective against all B. hyodysenteriae isolates tested, with a reduction of more than 5.00 log10 CFU/mL (bactericidal efficacy of 99.999%). However, some isolates exhibited reduced susceptibility to Virkon-S and Limoseptic disinfectants. The evaluation of cleaning and disinfection protocols on farms with SD outbreaks showed that approximately half the pens tested (n = 25) were positive by real-time PCR after pigs removal (mean B. hyodysenteriae counts 5.72 ± 1.04 log10 CFU/mL) while almost 20% of the pens remained positive after cleaning (n = 7) and disinfection (n = 5) procedures although with significantly lower, mean estimates (4.31 ± 0.43 log10 CFU/mL and 4.01 ± 0.55 log10 CFU/mL, respectively). CONCLUSIONS These results show the efficacy of disinfectants against B. hyodysenteriae but also stress the need to implement adequately the cleaning and disinfection protocols on pig farms and review and revise their efficiency periodically.
Collapse
Affiliation(s)
- Manuel Gómez-García
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain.
| | - Héctor Argüello
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Lucía Pérez-Pérez
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Clara Vega
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Héctor Puente
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Óscar Mencía-Ares
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Pedro Rubio
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| | - Ana Carvajal
- Department of Animal Health, Faculty of Veterinary Medicine, Universidad de León, León, Spain
| |
Collapse
|
8
|
Stubberfield E, Pringle M, Landén A, Veldman KT, Geurts Y, Jouy E, Le Devendec L, Rubin JE, Kulathunga DGRS, Kristensen KA, Chanter J, Bollard A, Johnson P, Maycock J, Habighorst-Blome K, Rohde J, Card RM. Validation of an antimicrobial susceptibility testing protocol for Brachyspira hyodysenteriae and Brachyspira pilosicoli in an international ring trial. Vet Microbiol 2020; 244:108645. [PMID: 32402332 DOI: 10.1016/j.vetmic.2020.108645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 02/27/2020] [Accepted: 03/17/2020] [Indexed: 10/24/2022]
Abstract
Brachyspira hyodysenteriae and Brachyspira pilosicoli cause economically important enteric disease in pigs. Treatment of these infections often includes antimicrobial administration, which can be most effective when therapeutic options are informed by antimicrobial susceptibility testing data. Here we describe a method for broth dilution antimicrobial susceptibility testing of these bacteria, both of which are difficult to culture in vitro. The protocol was evaluated for its fitness for use in an inter-laboratory ring trial involving eight laboratories from seven countries, and employing eleven test strains (5 Brachyspira hyodysenteriae including the type strain B78T and 6 Brachyspira pilosicoli) and six antibiotics. Overall intra- and inter-laboratory reproducibility of this method was very good (>90 % MICs at mode +/- 1 log2). Whole genome sequencing revealed good correspondence between reduced susceptibility and the presence of previously defined antimicrobial resistance determinants. Interestingly, lnu(C) was identified in B. pilosicoli isolates with elevated MICs of lincomycin, whilst tva(B) was associated with elevated MICs of pleuromutilins in this species. We designated two new control strains with MICs lying within currently tested ranges, including for the pleuromutilins, in contrast to the control strain B. hyodysenteriae B78T. These were deposited at the DSMZ-German Collection of Microorganisms and Cell Cultures GmbH. The validation of a standard protocol and identification of new control strains facilitates comparisons between studies, establishment of robust interpretative criteria, and ultimately contributes to rational antimicrobial use when treating infected livestock.
Collapse
Affiliation(s)
- E Stubberfield
- Department of Bacteriology, Animal and Plant Health Agency, Weybridge, Surrey, KT15 3NB, United Kingdom
| | - M Pringle
- Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute, SVA, SE-751 89, Uppsala, Sweden
| | - A Landén
- Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute, SVA, SE-751 89, Uppsala, Sweden
| | - K T Veldman
- Department of Bacteriology and Epidemiology, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Y Geurts
- Department of Bacteriology and Epidemiology, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - E Jouy
- Mycoplasmology-Bacteriology-Antimicrobial Resistance Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan, France
| | - L Le Devendec
- Mycoplasmology-Bacteriology-Antimicrobial Resistance Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan, France
| | - J E Rubin
- Department of Veterinary Microbiology, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - D G R S Kulathunga
- Department of Veterinary Microbiology, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - K A Kristensen
- National Food Institute, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
| | - J Chanter
- Animal and Plant Health Agency, Starcross VIC, Devon, United Kingdom
| | - A Bollard
- VETQAS Quality Assurance Unit, Animal and Plant Health Agency, Sutton Bonington, Leicestershire, United Kingdom
| | - P Johnson
- VETQAS Quality Assurance Unit, Animal and Plant Health Agency, Sutton Bonington, Leicestershire, United Kingdom
| | - J Maycock
- VETQAS Quality Assurance Unit, Animal and Plant Health Agency, Sutton Bonington, Leicestershire, United Kingdom
| | - K Habighorst-Blome
- Institute for Microbiology, University of Veterinary Medicine, Foundation, Bischofsholer Damm 15, 30173, Hannover, Germany
| | - J Rohde
- Institute for Microbiology, University of Veterinary Medicine, Foundation, Bischofsholer Damm 15, 30173, Hannover, Germany
| | - R M Card
- Department of Bacteriology, Animal and Plant Health Agency, Weybridge, Surrey, KT15 3NB, United Kingdom.
| |
Collapse
|
9
|
García-Martín AB, Schwendener S, Perreten V. The tva(A) Gene from Brachyspira hyodysenteriae Confers Decreased Susceptibility to Pleuromutilins and Streptogramin A in Escherichia coli. Antimicrob Agents Chemother 2019; 63:e00930-19. [PMID: 31307989 PMCID: PMC6709466 DOI: 10.1128/aac.00930-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/11/2019] [Indexed: 12/28/2022] Open
Abstract
The tva(A) gene suspected to confer resistance to pleuromutilins in Brachyspira hyodysenteriae was tested for functionality in Escherichia coli AG100A and Staphylococcus aureus RN4220. Expression of the cloned tva(A) gene conferred decreased susceptibility to pleuromutilin (P) and streptogramin A (SA) antibiotics in E. coli and had a minor effect in S. aureus The finding provides evidence of the direct association of tva(A) with the PSA resistance phenotype.
Collapse
Affiliation(s)
- Ana B García-Martín
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Sybille Schwendener
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Vincent Perreten
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| |
Collapse
|
10
|
Hampson DJ, Lugsomya K, La T, Phillips ND, Trott DJ, Abraham S. Antimicrobial resistance in Brachyspira - An increasing problem for disease control. Vet Microbiol 2018; 229:59-71. [PMID: 30642599 DOI: 10.1016/j.vetmic.2018.12.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/13/2018] [Accepted: 12/16/2018] [Indexed: 01/11/2023]
Abstract
Across all bacterial species the continuing reduction in susceptibility to antimicrobial agents is a critical and increasing threat for disease control. This mini-review outlines the extent of this problem amongst anaerobic intestinal spirochaetes of the genus Brachyspira, of which there are currently nine officially recognised species. These include some important pathogens that may cause colitis with diarrhoea and/or dysentery in various mammalian and avian species, but most notably in pigs and in adult chickens. The most economically significant pathogen is Brachyspira hyodysenteriae, the spirochaete which causes swine dysentery in countries throughout the world. Control of infections with Brachyspira species has long relied on the prophylactic or therapeutic use of antimicrobials, but increasingly strains with reduced susceptibility and sometimes multidrug resistance to previously effective antimicrobial agents are being encountered. In this mini-review we outline these problems and explain the extent and molecular basis of the emerging resistance. Future control will rely on developing and applying standardised methods for measuring antimicrobial susceptibility; improving surveillance of resistance using traditional phenotypic as well as genomic analysis of known resistance determinants; improving understanding of the molecular basis of resistance to different drug classes; improving farmer and veterinarian education about prudent antimicrobial use so as to reduce selective pressure on the emergence of resistance; and developing alternatives to antimicrobials as a means to control these infections.
Collapse
Affiliation(s)
- David J Hampson
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region; School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150, Australia.
| | - Kittitat Lugsomya
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
| | - Tom La
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150, Australia
| | - Nyree Dale Phillips
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150, Australia
| | - Darren J Trott
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, the University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Sam Abraham
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150, Australia
| |
Collapse
|
11
|
Card RM, Stubberfield E, Rogers J, Nunez-Garcia J, Ellis RJ, AbuOun M, Strugnell B, Teale C, Williamson S, Anjum MF. Identification of a New Antimicrobial Resistance Gene Provides Fresh Insights Into Pleuromutilin Resistance in Brachyspira hyodysenteriae, Aetiological Agent of Swine Dysentery. Front Microbiol 2018; 9:1183. [PMID: 29971045 PMCID: PMC6018095 DOI: 10.3389/fmicb.2018.01183] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/15/2018] [Indexed: 11/30/2022] Open
Abstract
Brachyspira hyodysenteriae is the aetiological agent of swine dysentery, a globally distributed disease that causes profound economic loss, impedes the free trade and movement of animals, and has significant impact on pig health. Infection is generally treated with antibiotics of which pleuromutilins, such as tiamulin, are widely used for this purpose, but reports of resistance worldwide threaten continued effective control. In Brachyspira hyodysenteriae pleuromutilin resistance has been associated with mutations in chromosomal genes encoding ribosome-associated functions, however the dynamics of resistance acquisition are poorly understood, compromising stewardship efforts to preserve pleuromutilin effectiveness. In this study we undertook whole genome sequencing (WGS) and phenotypic susceptibility testing of 34 UK field isolates and 3 control strains to investigate pleuromutilin resistance in Brachyspira hyodysenteriae. Genome-wide association studies identified a new pleuromutilin resistance gene, tva(A) (tiamulin valnemulin antibiotic resistance), encoding a predicted ABC-F transporter. In vitro culture of isolates in the presence of inhibitory or sub-inhibitory concentrations of tiamulin showed that tva(A) confers reduced pleuromutilin susceptibility that does not lead to clinical resistance but facilitates the development of higher-level resistance via mutations in genes encoding ribosome-associated functions. Genome sequencing of antibiotic-exposed isolates identified both new and previously described mutations in chromosomal genes associated with reduced pleuromutilin susceptibility, including the 23S rRNA gene and rplC, which encodes the L3 ribosomal protein. Interesting three antibiotic-exposed isolates harboured mutations in fusA, encoding Elongation Factor G, a gene not previously associated with pleuromutilin resistance. A longitudinal molecular epidemiological examination of two episodes of swine dysentery at the same farm indicated that tva(A) contributed to development of tiamulin resistance in vivo in a manner consistent with that seen experimentally in vitro. The in vitro studies further showed that tva(A) broadened the mutant selection window and raised the mutant prevention concentration above reported in vivo antibiotic concentrations obtained when administered at certain doses. We show how the identification and characterisation of tva(A), a new marker for pleuromutilin resistance, provides evidence to inform treatment regimes and reduce the development of resistance to this class of highly important antimicrobial agents.
Collapse
Affiliation(s)
- Roderick M Card
- Department of Bacteriology, Animal and Plant Health Agency (APHA), Addlestone, United Kingdom
| | - Emma Stubberfield
- APHA Veterinary Investigation Centre Bury St. Edmunds, Bury St Edmunds, United Kingdom
| | - Jon Rogers
- APHA Veterinary Investigation Centre Bury St. Edmunds, Bury St Edmunds, United Kingdom
| | - Javier Nunez-Garcia
- Central Sequencing Unit, Animal and Plant Health Agency (APHA), Addlestone, United Kingdom
| | - Richard J Ellis
- Central Sequencing Unit, Animal and Plant Health Agency (APHA), Addlestone, United Kingdom
| | - Manal AbuOun
- Department of Bacteriology, Animal and Plant Health Agency (APHA), Addlestone, United Kingdom
| | - Ben Strugnell
- Farm Post Mortems Ltd., Bishop Auckland, United Kingdom
| | - Christopher Teale
- APHA Veterinary Investigation Centre Shrewsbury, Shrewsbury, United Kingdom
| | - Susanna Williamson
- APHA Veterinary Investigation Centre Bury St. Edmunds, Bury St Edmunds, United Kingdom
| | - Muna F Anjum
- Department of Bacteriology, Animal and Plant Health Agency (APHA), Addlestone, United Kingdom
| |
Collapse
|
12
|
Yeh JC, Lo DY, Chang SK, Kuo HC. Antimicrobial Susceptibility Patterns of Brachyspira Species Isolated in Taiwan. Microb Drug Resist 2018; 24:685-692. [PMID: 29653474 DOI: 10.1089/mdr.2017.0188] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Some members of the Brachyspira genus cause diseases such as swine dysentery (SD) and porcine intestinal (or colonic) spirochetosis. Severe economic losses are caused by decreased feed intake and increased feed conversion ratio, as well as costs associated with treatment and death. A loss of clinical efficacy of some antimicrobial agents authorized for treating SD has been observed in many countries. The aim of this study was to analyze the antimicrobial susceptibility of Brachyspira isolated from Taiwan and to investigate the mechanism of decreased susceptibility to macrolides. A total of 55 Brachyspira isolates obtained from the grower-finisher period were evaluated in this study. These isolates included B. hyodysenteriae (n = 37), B. murdochii (n = 11), B. pilosicoli (n = 5), B. intermedia (n = 1), and B. innocens (n = 1). Antimicrobial susceptibility testing was performed to examine 12 selected antimicrobial agents. The results showed that the 50% and 90% minimum inhibitory concentration (MIC) values of the tested macrolides were all >256 μg/ml. The MIC50 of lincomycin, tiamulin, carbadox, olaquindox, ampicillin, amoxicillin, doxycycline, oxytetracycline, and gentamicin were 32, 1, ≤0.125, ≤0.125, 0.5, 0.25, 2, 2, and 2 μg/ml. The genetic basis of the decreased susceptibility to tylosin and lincomycin in Brachyspira spp. was investigated and the results showed a possible connection to the mutations at position A2058 and G2032 of the 23S rRNA gene. These findings demonstrated that, in Taiwan, there may be a decrease in susceptibility of Brachyspira spp. to antimicrobials commonly used for the treatment of SD.
Collapse
Affiliation(s)
- Jih-Ching Yeh
- 1 Department of Veterinary Medicine, College of Veterinary Medicine, National Chiayi University , Chiayi, Taiwan , ROC
| | - Dan-Yuan Lo
- 1 Department of Veterinary Medicine, College of Veterinary Medicine, National Chiayi University , Chiayi, Taiwan , ROC
| | - Shao-Kuang Chang
- 2 Graduate Institute of Veterinary Medicine, National Taiwan University , Taipei, Taiwan , ROC
| | - Hung-Chih Kuo
- 1 Department of Veterinary Medicine, College of Veterinary Medicine, National Chiayi University , Chiayi, Taiwan , ROC
| |
Collapse
|
13
|
Vadillo S, San-Juan C, Calderón M, Risco D, Fernández-Llario P, Pérez-Sancho M, Redondo E, Hurtado MA, Igeño MI. Isolation of Brachyspira species from farmed wild boar in Spain. Vet Rec 2017; 181:vetrec-2017-104348. [PMID: 28765497 DOI: 10.1136/vr.104348] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 05/06/2017] [Accepted: 06/04/2017] [Indexed: 12/28/2022]
Affiliation(s)
- Santiago Vadillo
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | - Carlos San-Juan
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | - Marta Calderón
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | - David Risco
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | | | | | - Eloy Redondo
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | - Miguel A Hurtado
- Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain
| | - M Isabel Igeño
- Departamento de Bioquímica y Biología Molecular y Genética, IPROCAR, Universidad de Extremadura, Cáceres, Spain
| |
Collapse
|
14
|
Kulathunga D, Rubin J. A review of the current state of antimicrobial susceptibility test methods for Brachyspira. Can J Microbiol 2017; 63:465-474. [DOI: 10.1139/cjm-2016-0756] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The re-emergence of swine dysentery (Brachyspira-associated muco-haemorrhagic colitis) since the late 2000s has illuminated diagnostic challenges associated with this genus. The methods used to detect, identify, and characterize Brachyspira from clinical samples have not been standardized, and laboratories frequently rely heavily on in-house techniques. Particularly concerning is the lack of standardized methods for determining and interpreting the antimicrobial susceptibility of Brachyspira spp. The integration of laboratory data into a treatment plan is a critical component of prudent antimicrobial usage. Therefore, the lack of standardized methods is an important limitation to the evidence-based use of antimicrobials. This review will focus on describing the methodological limitations and inconsistencies between current susceptibility testing schemes employed for Brachyspira, provide an overview of what we do know about the susceptibility of these organisms, and suggest future directions to improve and standardize diagnostic strategies.
Collapse
Affiliation(s)
- D.G.R.S. Kulathunga
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
| | - J.E. Rubin
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
| |
Collapse
|
15
|
Daniel AG, Sato JP, Gabardo MP, Resende TP, Barcellos DED, Pereira CE, Vannucci FA, Guedes RM. Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains. PESQUISA VETERINARIA BRASILEIRA 2017. [DOI: 10.1590/s0100-736x2017000400006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ABSTRACT: The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8μg/ml for doxycycline, >4μg/ml for valnemulin, 8μg/ml for tiamulin, 32μg/ml for tylvalosin, >64μg/ml for lincomycin and >128μg/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Fábio A. Vannucci
- Microvet-Microbiologia Veterinária Especial, Brasil; University of Minnesota, USA
| | | |
Collapse
|
16
|
Antimicrobial Susceptibility Patterns of Brachyspira Species Isolated from Swine Herds in the United States. J Clin Microbiol 2016; 54:2109-19. [PMID: 27252458 DOI: 10.1128/jcm.00834-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 05/24/2016] [Indexed: 12/12/2022] Open
Abstract
Outbreaks of swine dysentery, caused by Brachyspira hyodysenteriae and the recently discovered "Brachyspira hampsonii," have reoccurred in North American swine herds since the late 2000s. Additionally, multiple Brachyspira species have been increasingly isolated by North American diagnostic laboratories. In Europe, the reliance on antimicrobial therapy for control of swine dysentery has been followed by reports of antimicrobial resistance over time. The objectives of our study were to determine the antimicrobial susceptibility trends of four Brachyspira species originating from U.S. swine herds and to investigate their associations with the bacterial species, genotypes, and epidemiological origins of the isolates. We evaluated the susceptibility of B. hyodysenteriae, B. hampsonii, Brachyspira pilosicoli, and Brachyspira murdochii to tiamulin, valnemulin, doxycycline, lincomycin, and tylosin by broth microdilution and that to carbadox by agar dilution. In general, Brachyspira species showed high susceptibility to tiamulin, valnemulin, and carbadox, heterogeneous susceptibility to doxycycline, and low susceptibility to lincomycin and tylosin. A trend of decreasing antimicrobial susceptibility by species was observed (B. hampsonii > B. hyodysenteriae > B. murdochii > B. pilosicoli). In general, Brachyspira isolates from the United States were more susceptible to these antimicrobials than were isolates from other countries. Decreased antimicrobial susceptibility was associated with the genotype, stage of production, and production system from which the isolate originated, which highlights the roles of biosecurity and husbandry in disease prevention and control. Finally, this study also highlights the urgent need for Clinical and Laboratory Standards Institute-approved clinical breakpoints for Brachyspira species, to facilitate informed therapeutic and control strategies.
Collapse
|
17
|
Mirajkar NS, Gebhart CJ. Comparison of agar dilution and antibiotic gradient strip test with broth microdilution for susceptibility testing of swine Brachyspira species. J Vet Diagn Invest 2016; 28:133-43. [DOI: 10.1177/1040638716629154] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Production-limiting diseases in swine caused by Brachyspira are characterized by mucohemorrhagic diarrhea ( B. hyodysenteriae and “ B. hampsonii”) or mild colitis ( B. pilosicoli), while B. murdochii is often isolated from healthy pigs. Emergence of novel pathogenic Brachyspira species and strains with reduced susceptibility to commonly used antimicrobials has reinforced the need for standardized susceptibility testing. Two methods are currently used for Brachyspira susceptibility testing: agar dilution (AD) and broth microdilution (BMD). However, these tests have primarily been used for B. hyodysenteriae and rarely for B. pilosicoli. Information on the use of commercial susceptibility testing products such as antibiotic gradient strips is lacking. Our main objective was to validate and compare the susceptibility results, measured as the minimum inhibitory concentration (MIC), of 6 antimicrobials for 4 Brachyspira species ( B. hyodysenteriae, “ B. hampsonii”, B. pilosicoli, and B. murdochii) by BMD and AD (tiamulin, valnemulin, lincomycin, tylosin, and carbadox) or antibiotic gradient strip (doxycycline) methods. In general, the results of a high percentage of all 4 Brachyspira species differed by ±1 log2 dilution or less by BMD and AD for tiamulin, valnemulin, lincomycin, and tylosin, and by BMD and antibiotic gradient strip for doxycycline. The carbadox MICs obtained by BMD were 1–5 doubling dilutions different than those obtained by AD. BMD for Brachyspira was quicker to perform with less ambiguous interpretation of results when compared with AD and antibiotic gradient strip methods, and the results confirm the utility of BMD in routine diagnostics.
Collapse
Affiliation(s)
- Nandita S. Mirajkar
- Department of Veterinary and Biomedical Sciences (Mirajkar, Gebhart), College of Veterinary Medicine, University of Minnesota, Saint Paul, MN
- Veterinary Diagnostic Laboratory (Gebhart), College of Veterinary Medicine, University of Minnesota, Saint Paul, MN
| | - Connie J. Gebhart
- Department of Veterinary and Biomedical Sciences (Mirajkar, Gebhart), College of Veterinary Medicine, University of Minnesota, Saint Paul, MN
- Veterinary Diagnostic Laboratory (Gebhart), College of Veterinary Medicine, University of Minnesota, Saint Paul, MN
| |
Collapse
|
18
|
Le Roy CI, Mappley LJ, La Ragione RM, Woodward MJ, Claus SP. Brachyspira pilosicoli-induced avian intestinal spirochaetosis. MICROBIAL ECOLOGY IN HEALTH AND DISEASE 2015; 26:28853. [PMID: 26679774 PMCID: PMC4683989 DOI: 10.3402/mehd.v26.28853] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 11/22/2022]
Abstract
Avian intestinal spirochaetosis (AIS) is a common disease occurring in poultry that can be caused by Brachyspira pilosicoli, a Gram-negative bacterium of the order Spirochaetes. During AIS, this opportunistic pathogen colonises the lower gastrointestinal (GI) tract of poultry (principally, the ileum, caeca, and colon), which can cause symptoms such as diarrhoea, reduced growth rate, and reduced egg production and quality. Due to the large increase of bacterial resistance to antibiotic treatment, the European Union banned in 2006 the prophylactic use of antibiotics as growth promoters in livestock. Consequently, the number of outbreaks of AIS has dramatically increased in the UK resulting in significant economic losses. This review summarises the current knowledge about AIS infection caused by B. pilosicoli and discusses various treatments and prevention strategies to control AIS.
Collapse
Affiliation(s)
- Caroline I Le Roy
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Luke J Mappley
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Roberto M La Ragione
- Faculty of Health and Medical Sciences, School of Veterinary Medicine, University of Surrey, Guilford, UK.,Department of Bacteriology, APHA, Weybridge, UK
| | - Martin J Woodward
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Sandrine P Claus
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK;
| |
Collapse
|
19
|
Jansson DS, Mushtaq M, Johansson KE, Bonnedahl J, Waldenström J, Andersson DI, Broman T, Berg C, Olsen B. Intestinal spirochaetes (genus Brachyspira) colonise wild birds in the southern Atlantic region and Antarctica. Infect Ecol Epidemiol 2015; 5:29296. [PMID: 26584828 PMCID: PMC4653322 DOI: 10.3402/iee.v5.29296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/19/2015] [Accepted: 10/22/2015] [Indexed: 11/14/2022] Open
Abstract
Introduction The genus Brachyspira contains well-known enteric pathogens of veterinary significance, suggested agents of colonic disease in humans, and one potentially zoonotic agent. There are recent studies showing that Brachyspira are more widespread in the wildlife community than previously thought. There are no records of this genus in wildlife from the southern Atlantic region and Antarctica. Our aim was therefore, to determine whether intestinal spirochaetes of genus Brachyspira colonise marine and coastal birds in this region. Method Faecal samples were collected from marine and coastal birds in the southern Atlantic region, including sub-Antarctic islands and Antarctica, in 2002, 2009, and 2012, with the aim to isolate and characterise zoonotic agents. In total, 205 samples from 11 bird species were selectively cultured for intestinal spirochaetes of genus Brachyspira. To identify isolates to species level, they were subjected to phenotyping, species-specific polymerase chain reactions, sequencing of partial 16S rRNA, NADH oxidase (nox), and tlyA genes, and phylogenetic analysis. Antimicrobial susceptibility tests were performed. Results Fourteen unique strains were obtained from 10 birds of three species: four snowy sheathbills (Chionis albus), three kelp geese (Chloephaga hybrida subsp. malvinarum), and three brown skua (Stercorarius antarcticus subsp. lonnbergi) sampled on the Falkland Islands, Tierra del Fuego in Argentina, South Georgia, South Shetland Islands, and the Antarctic Peninsula. Five Brachyspira strains were closely related to potentially enteropathogenic Brachyspira sp. of chickens: B. intermedia (n=2, from snowy sheathbills), and B. alvinipulli (n=3, from a kelp goose and two snowy sheathbills). Three strains from kelp geese were most similar to the presumed non-pathogenic species ‘B. pulli’ and B. murdochii, whereas the remaining six strains could not be attributed to currently known species. No isolates related to human strains were found. None of the tested strains showed decreased susceptibility to tiamulin, valnemulin, doxycycline, tylvalosin, lincomycin, or tylosin. Conclusions This is the first report of intestinal spirochaetes from this region. Despite limitations of current diagnostic methods, our results, together with earlier studies, show that Brachyspira spp., including potentially pathogenic strains, occur globally among free-living avian hosts, and that this genus encompasses a higher degree of biodiversity than previously recognised.
Collapse
Affiliation(s)
- Désirée S Jansson
- Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute, Uppsala, Sweden;
| | - Memoona Mushtaq
- Department of Animal Breeding and Genetics, Global Bioinformatics Centre, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden
| | - Karl-Erik Johansson
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Jonas Bonnedahl
- Department of Infectious Diseases, Kalmar County Hospital, Kalmar, Sweden.,Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Jonas Waldenström
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Dan I Andersson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Tina Broman
- Division of CBRN Defence and Security, FOI - Swedish Defence Research Agency, Umeå, Sweden
| | - Charlotte Berg
- Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Skara, Sweden
| | - Björn Olsen
- Section of Infectious Diseases, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| |
Collapse
|
20
|
Rugna G, Bonilauri P, Carra E, Bergamini F, Luppi A, Gherpelli Y, Magistrali CF, Nigrelli A, Alborali GL, Martelli P, La T, Hampson DJ, Merialdi G. Sequence types and pleuromutilin susceptibility of Brachyspira hyodysenteriae isolates from Italian pigs with swine dysentery: 2003-2012. Vet J 2015; 203:115-9. [PMID: 25486860 DOI: 10.1016/j.tvjl.2014.10.033] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/15/2014] [Accepted: 10/28/2014] [Indexed: 10/24/2022]
Abstract
Swine dysentery is a mucohaemorrhagic colitis of pigs caused by infection with Brachyspira hyodysenteriae. The disease can be controlled by treatment with antimicrobial agents, with the pleuromutilins tiamulin and valnemulin being widely used. In recent years, the occurrence of B. hyodysenteriae with reduced susceptibility to these drugs has been increasing. The aim of this study was to determine temporal changes in genetic groups and pleuromutilin susceptibility amongst B. hyodysenteriae isolates from Italy. Multilocus sequence typing (MLST) was performed on 108 isolates recovered from 87 farms in different regions of Italy from 2003 to 2012, and their minimum inhibitory concentrations (MICs) for tiamulin and valnemulin were determined. Logistic regression was performed to assess associations between susceptibility to the two antimicrobial agents and genetic group, year and region of isolation. The isolates were allocated to 23 sequence types (STs), with five clonal clusters (Ccs) and seven singletons. More than 50% of isolates were resistant to both pleuromutilins (MIC >2.0 µg/mL for tiamulin and >1.0 µg/mL for valnemulin). All 10 isolates in ST 83 were resistant; these were first isolated in 2011 and came from nine farms, suggesting recent widespread dissemination of a resistant strain. Significant associations were found between the proportion of pleuromutilin susceptible isolates and the genetic group and year of isolation. Although resistant isolates were found in all Ccs, isolates in Ccs 2 and 7 were over five times more likely to be susceptible than those in the other Ccs. A significant trend in the reduction of susceptibility over time also was observed.
Collapse
Affiliation(s)
- G Rugna
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy.
| | - P Bonilauri
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - E Carra
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - F Bergamini
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - A Luppi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - Y Gherpelli
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - C F Magistrali
- Istituto Zooprofilattico Sperimentale Umbria e Marche, Via G. Salvemini 1, 06126 Perugia, Italy
| | - A Nigrelli
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - G L Alborali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| | - P Martelli
- Department of Veterinary Science, University of Parma, Via del Taglio 10, 43126 Parma, Italy
| | - T La
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - D J Hampson
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - G Merialdi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 9, 25124 Brescia, Italy
| |
Collapse
|
21
|
Hillen S, Willems H, Herbst W, Rohde J, Reiner G. Mutations in the 50S ribosomal subunit of Brachyspira hyodysenteriae associated with altered minimum inhibitory concentrations of pleuromutilins. Vet Microbiol 2014; 172:223-9. [PMID: 24948419 DOI: 10.1016/j.vetmic.2014.04.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 04/25/2014] [Accepted: 04/28/2014] [Indexed: 11/21/2022]
Abstract
Brachyspira hyodysenteriae, the causative agent of swine dysentery, is responsible for severe mucohaemorrhagic colitis with considerable financial loss to worldwide swine production. Antimicrobial resistance against macrolides and lincosamides is widespread and the mechanisms are well known. Currently, the most common treatment for swine dysentery is the use of pleuromutilins and resistance to these drugs also is increasingly being reported. Although resistance mechanisms against pleuromutilins are less clear than for other drugs, they seem to involve alterations of the peptidyl transferase centre (PTC), including ribosomal RNA and the ribosomal protein L3. The present study was conducted to examine molecular mechanisms of resistance on a representative set of B. hyodysenteriae field strains with different resistance patterns. In total, we identified 24 single nucleotide polymorphisms (SNPs) in the 23S rRNA gene and genes of the ribosomal proteins L3, L4, L2 and L22. The SNP in the ribosomal protein gene L3 at position 443 led to an amino acid substitution of asparagine (Asn) by serine (Ser) at position 148, significantly associated with MICs for pleuromutilins. Based on this SNP a correct assignment of 71% of the strains with respect to a threshold of >0.625 μg tiamulin/ml was reached. Unexpectedly low MICs in some of the Asn-strains were explained by a second SNP at position 2535 of the 23S rRNA. Our results clearly show the associations between MICs for pleuromutilins and mutations in their binding site. A complete list of SNPs that influence MICs of B. hyodysenteriae strains is needed to enable the interpretation of future molecular susceptibility testing.
Collapse
Affiliation(s)
- Sonja Hillen
- Department of Veterinary Clinical Sciences, Clinic for Swine, JLU Giessen, Germany
| | - Hermann Willems
- Department of Veterinary Clinical Sciences, Clinic for Swine, JLU Giessen, Germany
| | - Werner Herbst
- Institute for Hygiene and Infectious Diseases of Animals, JLU Giessen, Germany
| | - Judith Rohde
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine, Hannover, Germany
| | - Gerald Reiner
- Department of Veterinary Clinical Sciences, Clinic for Swine, JLU Giessen, Germany.
| |
Collapse
|
22
|
van Duijkeren E, Greko C, Pringle M, Baptiste KE, Catry B, Jukes H, Moreno MA, Pomba MCMF, Pyörälä S, Rantala M, Ružauskas M, Sanders P, Teale C, Threlfall EJ, Torren-Edo J, Törneke K. Pleuromutilins: use in food-producing animals in the European Union, development of resistance and impact on human and animal health. J Antimicrob Chemother 2014; 69:2022-31. [PMID: 24793902 DOI: 10.1093/jac/dku123] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
Pleuromutilins (tiamulin and valnemulin) are antimicrobial agents that are used mainly in veterinary medicine, especially for swine and to a lesser extent for poultry and rabbits. In pigs, tiamulin and valnemulin are used to treat swine dysentery, spirochaete-associated diarrhoea, porcine proliferative enteropathy, enzootic pneumonia and other infections where Mycoplasma is involved. There are concerns about the reported increases in the MICs of tiamulin and valnemulin for porcine Brachyspira hyodysenteriae isolates from different European countries, as only a limited number of antimicrobials are available for the treatment of swine dysentery where resistance to these antimicrobials is already common and widespread. The loss of pleuromutilins as effective tools to treat swine dysentery because of further increases in resistance or as a consequence of restrictions would present a considerable threat to pig health, welfare and productivity. In humans, only one product containing pleuromutilins (retapamulin) is authorized currently for topical use; however, products for oral and intravenous administration to humans with serious multidrug-resistant skin infections and respiratory infections, including those caused by methicillin-resistant Staphylococcus aureus (MRSA), are being developed. The objective of this review is to summarize the current knowledge on the usage of pleuromutilins, resistance development and the potential impact of this resistance on animal and human health.
Collapse
Affiliation(s)
| | | | | | | | | | - Helen Jukes
- Veterinary Medicines Directorate, Addlestone, UK
| | - Miguel A Moreno
- Faculty of Veterinary Medicine, Complutense University, Madrid, Spain
| | | | - Satu Pyörälä
- Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Merja Rantala
- Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Modestas Ružauskas
- Veterinary Institute, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Pascal Sanders
- Agence Nationale de Sécurité Sanitaire (ANSES), Fougères, France
| | | | | | | | | |
Collapse
|
23
|
Pharmacological and structure-activity relationship evaluation of 4-aryl-1-diphenylacetyl(thio)semicarbazides. Molecules 2014; 19:4745-59. [PMID: 24743932 PMCID: PMC6271380 DOI: 10.3390/molecules19044745] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 03/27/2014] [Accepted: 04/03/2014] [Indexed: 12/01/2022] Open
Abstract
This article describes the synthesis of six 4-aryl-(thio)semicarbazides (series a and b) linked with diphenylacetyl moiety along with their pharmacological evaluation on the central nervous system in mice and computational studies, including conformational analysis and electrostatic properties. All thiosemicarbazides (series b) were found to exhibit strong antinociceptive activity in the behavioural model. Among them, compound 1-diphenylacetyl-4-(4-methylphenyl)thiosemicarbazide 1b was found to be the most potent analgesic agent, whose activity is connected with the opioid system. For compounds from series a significant anti-serotonergic effect, especially for compound 1-diphenylacetyl-4-(4-methoxyphenyl)semicarbazide 2b was observed. The computational studies strongly support the obtained results.
Collapse
|
24
|
Antibiotic susceptibility of Brachyspira hyodysenteriae isolates from Czech swine farms: a 10-year follow-up study. ACTA VET BRNO 2014. [DOI: 10.2754/avb201483010003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Brachyspira hyodysenteriae is the causative agent of swine dysentery. Loss of clinical efficacy of some antimicrobial agents authorized for treating swine dysentery was observed on certain Czech pig farms. The aim of the present study was to evaluate the antimicrobial sensitivity of six antibiotics using a set of 202 randomly selected B. hyodysenteriae isolates obtained from farms in the Czech Republic between years 1997 and 2006. Minimum inhibitory concentration of antibiotics tylosin, lincomycin, tylvalosin, chlortetracyclin, tiamulin and valnemulin were tested, using an agar dilution method. All antibiotics tested showed an increase in minimal inhibitory concentrations. Continual decrease in susceptibility of B. hyodysenteriae isolates to tiamulin and valnemulin was observed. Multiresistant B. hyodysenteriae were isolated more frequently in the past years. Only a careful use of antibiotics can ensure their efficacy, especially in case of pleuromutilins, in the strategic therapy of swine dysentery. This rare study demonstrates the minimal inhibitory concentration changes of selected antidysenterics among Czech isolates of Brachyspira hyodysenteriae during a ten-year period.
Collapse
|
25
|
Herbst W, Schlez K, Heuser J, Baljer G. Antimicrobial susceptibility of Brachyspira hyodysenteriae determined by a broth microdilution method. Vet Rec 2014; 174:382. [PMID: 24659031 DOI: 10.1136/vr.102169] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- W Herbst
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-Universität Giessen, Frankfurter Strasse 89, 35392 Giessen, Germany
| | | | | | | |
Collapse
|
26
|
Pitucha M, Olender A, Wujec M, Borowski P, Mardarowicz M. Synthesis and Antibacterial Evaluation of Some Semicarbazides and 1,2,4-Triazol-5-Ones Containing Thiophene Moieties. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.201000040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
27
|
Swine dysentery: aetiology, pathogenicity, determinants of transmission and the fight against the disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:1927-47. [PMID: 23665849 PMCID: PMC3709357 DOI: 10.3390/ijerph10051927] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/22/2013] [Accepted: 04/23/2013] [Indexed: 11/18/2022]
Abstract
Swine Dysentery (SD) is a severe mucohaemorhagic enteric disease of pigs caused by Brachyspira hyodysenteriae, which has a large impact on pig production and causes important losses due to mortality and sub-optimal performance. Although B. hyodysenteriae has been traditionally considered a pathogen mainly transmitted by direct contact, through the introduction of subclinically infected animals into a previously uninfected herd, recent findings position B. hyodysenteriae as a potential threat for indirect transmission between farms. This article summarizes the knowledge available on the etiological agent of SD and its virulence traits, and reviews the determinants of SD transmission. The between-herds and within-herd transmission routes are addressed. The factors affecting disease transmission are thoroughly discussed, i.e., environmental survival of the pathogen, husbandry factors (production system, production stage, farm management), role of vectors, diet influence and interaction of the microorganism with gut microbiota. Finally, prophylactic and therapeutic approaches to fight against the disease are briefly described.
Collapse
|
28
|
Pringle M, Landén A, Unnerstad HE, Molander B, Bengtsson B. Antimicrobial susceptibility of porcine Brachyspira hyodysenteriae and Brachyspira pilosicoli isolated in Sweden between 1990 and 2010. Acta Vet Scand 2012; 54:54. [PMID: 22998753 PMCID: PMC3526423 DOI: 10.1186/1751-0147-54-54] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 09/16/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The anaerobic spirochetes Brachyspira hyodysenteriae and Brachyspira pilosicoli cause diarrheal diseases in pigs. Their fastidious nature has hampered standardization of methods for antimicrobial susceptibility testing. For monitoring of antimicrobial susceptibility wild type cutoff values are needed to define where the wild type distribution of MICs ends and no approved cutoffs are available for Brachyspira spp. In this study antimicrobial susceptibility data for both species (in total 906 isolates) were compiled and analyzed and wild type cut off values for B. hyodysenteriae proposed. METHODS The MICs of tiamulin, valnemulin, tylosin, tylvalosin, doxycycline and lincomycin were determined by broth dilution in brain heart infusion broth supplemented with 10% fetal calf serum. RESULTS The compiled MICs from the broth dilution tests of the B. hyodysenteriae type strain, B78T (ATCC® 27164T), showed that the method yields reproducible results. In an international perspective the frequencies of isolates with decreased antimicrobial susceptibility were low among both B. hyodysenteriae and B. pilosicoli. However, in B. pilosicoli a constant level of 10-15% isolates with tiamulin MICs >4 μg/ml was detected between 2002 and 2010 and in B. hyodysenteriae a gradual increase in tiamulin MICs was seen between 1990 and 2003 although this increase has ceased during the last years. The wild type cutoff values proposed for B. hyodysenteriae are: tiamulin >0.25 μg/ml, valnemulin >0.125 μg/ml, tylosin >16 μg/ml, tylvalosin >1 μg/ml, lincomycin >1 μg/ml and doxycycline >0.5 μg/ml. CONCLUSIONS The broth dilution method used in this study has over the years generated tightly grouped MIC populations for the field isolates and reproducible results for the control strain B78T and is therefore a suitable antimicrobial susceptibility test method for monitoring of Brachyspira spp. Here we propose wild type cutoff values for six antimicrobial agents for B. hyodysenteriae tested by broth dilution based on MIC distributions and the current knowledge on mechanisms of resistance in this species. There are few studies on antimicrobial resistance mechanisms and MIC distributions in B. pilosicoli but to some extent the cutoff values proposed for B. hyodysenteriae may be applicable also for monitoring of antimicrobial susceptibility in B. pilosicoli.
Collapse
|
29
|
Antimicrobial susceptibility of Brachyspira hyodysenteriae isolated from 21 Polish farms. Pol J Vet Sci 2012; 15:259-65. [PMID: 22844703 DOI: 10.2478/v10181-011-0143-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Swine dysentery (SD) is a common disease among pigs worldwide, which contributes to major production losses. Antimicrobial susceptibility testing of B. hyodysenteriae, the etiological agent of SD, is mainly performed by the agar dilution method. This method has certain limitations due to difficulties in interpretation of results. The aim of this study was the analysis of antimicrobial susceptibility of Brachyspira hyodysenteriae (B. hyodysenteriae) Polish field isolates by broth microdilution procedure. The study was performed on 21 isolates of B. hyodysenteriae, collected between January 2006 to December 2010 from cases of swine dysentery. VetMIC Brachyspira panels with antimicrobial agents (tiamulin, valnemulin, doxycycline, lincomycin, tylosin and ampicillin) were used for susceptibility testing of B. hyodysenteriae. The minimal inhibitory concentration (MIC) was determined by the broth dilution procedure. The lowest antimicrobial activity was demonstrated for tylosin and lincomycin, with inhibition of bacterial growth using concentrations > 128 microg/ml and 32 microg/ml, respectively. In the case of doxycycline, the MIC values were < or = 2.0 microg/ml. No decreased susceptibility to tiamulin was found among the Polish isolates and MIC values for this antibiotic did not exceed 1.0 microg/ml. The results of the present study confirmed that Polish B. hyodysenteriae isolates were susceptible to the main antibiotics (tiamulin and valnemulin) used in treatment of swine dysentery. Further studies are necessary to evaluate a possible slow decrease in susceptibility to tiamulin and valnemulin of B. hyodysenteriae strains in Poland.
Collapse
|
30
|
Clothier KA, Kinyon JM, Frana TS, Naberhaus N, Bower L, Strait EL, Schwartz K. Species characterization and minimum inhibitory concentration patterns of Brachyspira species isolates from swine with clinical disease. J Vet Diagn Invest 2011; 23:1140-5. [DOI: 10.1177/1040638711425580] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Typhlocolitis and dysentery due to Brachyspira hyodysenteriae infection represent an economically important disease syndrome in growing pigs. Largely disappearing from U.S. swine herds in the late 1990s and early 2000s, Brachyspira-associated disease and bacterial isolation from swine with clinical disease has increased in the last several years, and non– B. hyodysenteriae isolates are commonly identified. Antimicrobial resistance has been demonstrated in Brachyspira spp. isolates from Europe and Asia, and may be the reason for the resurgence in U.S. herds. Seventy-nine clinical isolates identified at the Iowa State University Veterinary Diagnostic Lab were tested with multiple polymerase chain reaction assays to establish species identity, and evaluated for minimum inhibitory concentrations (MICs) using an agar dilution method against lincomycin, gentamicin, valnemulin, tiamulin, salinomycin, and carbadox. Only 38.0% of isolates could be confirmed as the known pathogens B. hyodysenteriae (30.4%) or Brachyspira pilosicoli (7.6%). Twenty of the 79 isolates (25.3%) were identified as Brachyspira murdochii, and 13.9% could not be identified to species. The MIC values were consistently high against lincomycin and moderately high against gentamicin. The remaining antimicrobials had MICs that were at the low end of the test ranges. Brachyspira murdochii and Brachyspira spp. had significantly greater MIC values against several of these drugs than other Brachyspira spp. examined. The increased incidence of these less definitively characterized Brachyspira species with increased MIC values to commonly prescribed antimicrobials may, at least in part, explain the increased prevalence and severity of this disease complex in recent years. Further research is necessary to understand these changes.
Collapse
Affiliation(s)
- Kristin A. Clothier
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Joann M. Kinyon
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Timothy S. Frana
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Nadine Naberhaus
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Leslie Bower
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Erin L. Strait
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| | - Kent Schwartz
- Iowa State University Veterinary Diagnostic Laboratory, Department of Veterinary and Production Animal Medicine, Iowa State University, College of Veterinary Medicine, Ames, IA
| |
Collapse
|
31
|
Lobova D, Prasek J, Cizek A, Celer V. Evaluation of the use of recombinant Bhlp29.7 in immunoblotting with pig serum as a means to identify herds infected with Brachyspira hyodysenteriae. Lett Appl Microbiol 2011; 53:466-72. [PMID: 21838749 DOI: 10.1111/j.1472-765x.2011.03134.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Aim of the study is to evaluate the use of recombinant Bhlp29.7 in immunoblotting with sera as a means to detect pig herds infected with Brachyspira hyodysenteriae. METHODS AND RESULTS Sera samples from 789 sows and rectal swabs from 838 pigs of various categories on 22 farms of different size (median 450 animals), production type and history of swine dysentery (SD) were examined. Sera from 378 sows from farms with previous SD history were examined via immunoblotting. Specific antibodies were detected in 79 of these (20.9%). Examination of 411 serum samples from sows and gilts taken on 11 farms without previous history of SD detected specific antibodies in 13 sows and gilts (3.2%). These 13, however, had come from farms where the presence of B. hyodysenteriae was confirmed or SD status was not known. Seroprevalence in herds with previous SD history ranged from 2.5 to 35.7%. B. hyodysenteriae was confirmed on six (27.3%) of 22 monitored farms. CONCLUSIONS Immunoblotting using recombinant antigen Bhlp29.7 in conjunction with culturing B. hyodysenteriae proved to be a valuable tool for detecting swine herds latently infected with B. hyodysenteriae. SIGNIFICANCE AND IMPACT OF THE STUDY The use of immunoblotting with recombinant Bhlp29.7 should prove to be a useful adjunct to detecting herds with SD, and hence, it will assist in controlling this important disease.
Collapse
Affiliation(s)
- D Lobova
- Institute of Infectious Diseases and Microbiology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | | | | | | |
Collapse
|
32
|
Jansson DS, Pringle M. Antimicrobial susceptibility ofBrachyspiraspp. isolated from commercial laying hens and free-living wild mallards (Anas platyrhynchos). Avian Pathol 2011; 40:387-93. [DOI: 10.1080/03079457.2011.588197] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
33
|
Verlinden M, Boyen F, Pasmans F, Garmyn A, Haesebrouck F, Martel A. Antimicrobial susceptibility pattern of Brachyspira intermedia isolates from European layers. Microb Drug Resist 2011; 17:485-8. [PMID: 21663534 DOI: 10.1089/mdr.2011.0082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A broth microdilution method was used to determine the antimicrobial susceptibility of 20 Brachyspira intermedia isolates obtained from different layer flocks in Belgium and The Netherlands between 2008 and 2010. The antimicrobial agents used were tylosin, tilmicosin, tiamulin, valnemulin, doxycycline, and lincomycin. The minimal inhibitory concentration (MIC) distribution patterns of tylosin, tilmicosin, lincomycin, and doxycycline were bimodal, demonstrating acquired resistance against doxycycline in three strains, against the macrolides in two strains, and against lincomycin in one strain. The MICs of tiamulin and valnemulin showed a monomodal distribution, but with tailing toward the higher MIC values, possibly suggesting low-level acquired resistance in six isolates. Sequencing revealed a G1058C mutation in the 16S rRNA gene in all doxycycline-resistant strains. The strain resistant to tylosin, tilmicosin, and lincomycin had an A2058T mutation in the 23S rRNA gene.
Collapse
Affiliation(s)
- Marc Verlinden
- Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | | | | | | | | | | |
Collapse
|
34
|
Lactobacilli antagonize the growth, motility, and adherence of Brachyspira pilosicoli: a potential intervention against avian intestinal spirochetosis. Appl Environ Microbiol 2011; 77:5402-11. [PMID: 21666022 DOI: 10.1128/aem.00185-11] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Avian intestinal spirochetosis (AIS) results from the colonization of the ceca and colorectum of poultry by pathogenic Brachyspira species. The number of cases of AIS has increased since the 2006 European Union ban on the use of antibiotic growth promoters, which, together with emerging antimicrobial resistance in Brachyspira, has driven renewed interest in alternative intervention strategies. Probiotics have been reported as protecting livestock against infection with common enteric pathogens, and here we investigate which aspects of the biology of Brachyspira they antagonize in order to identify possible interventions against AIS. The cell-free supernatants (CFS) of two Lactobacillus strains, Lactobacillus reuteri LM1 and Lactobacillus salivarius LM2, suppressed the growth of Brachyspira pilosicoli B2904 in a pH-dependent manner. In in vitro adherence and invasion assays with HT29-16E three-dimensional (3D) cells and in a novel avian cecal in vitro organ culture (IVOC) model, the adherence and invasion of B. pilosicoli in epithelial cells were reduced significantly by the presence of lactobacilli (P < 0.001). In addition, live and heat-inactivated lactobacilli inhibited the motility of B. pilosicoli, and electron microscopic observations indicated that contact between the lactobacilli and Brachyspira was crucial in inhibiting both adherence and motility. These data suggest that motility is essential for B. pilosicoli to adhere to and invade the gut epithelium and that any interference of motility may be a useful tool for the development of control strategies.
Collapse
|
35
|
Trends towards lower antimicrobial susceptibility and characterization of acquired resistance among clinical isolates of Brachyspira hyodysenteriae in Spain. Antimicrob Agents Chemother 2011; 55:3330-7. [PMID: 21555771 DOI: 10.1128/aac.01749-10] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antimicrobial susceptibility of clinical isolates of Brachyspira hyodysenteriae in Spain was monitored, and the underlying molecular mechanisms of resistance were investigated. MICs of tylosin, tiamulin, valnemulin, lincomycin, and tylvalosin were determined for 87 B. hyodysenteriae isolates recovered from 2008 to 2009 by broth dilution. Domain V of the 23S rRNA gene and the ribosomal protein L3 gene were sequenced in 20 isolates for which the tiamulin MIC was ≥ 4 μg/ml, presenting decreased susceptibility, and in 18 tiamulin-susceptible isolates (MIC ≤ 0.125 μg/ml), and all isolates were typed by multiple-locus variable-number tandem repeats analysis. A comparison with antimicrobial susceptibility data from 2000 to 2007 showed an increase in pleuromutilin resistance over time, doubling the number of isolates with decreased susceptibility to tiamulin. No alteration in susceptibility was detected for lincomycin, and the MIC of tylosin remained high (MIC(50) > 128 μg/ml). The decreased susceptibility to tylosin and lincomycin can be explained by mutations at position A2058 of the 23S rRNA gene (Escherichia coli numbering). A2058T was the predominant mutation, but A2058G also was found together with a change of the neighboring base pair at positions 2057 to 2611. The role of additional point mutations in the vicinity of the peptidyl transferase center and mutations in the L3 at amino acids 148 and 149 and their possible involvement in antimicrobial susceptibility are considered. An association between G2032A and high levels of tiamulin and lincomycin MICs was found, suggesting an increasing importance of this mutation in antimicrobial resistance of clinical isolates of B. hyodysenteriae.
Collapse
|
36
|
Ohya T, Sueyoshi M. In vitro antimicrobial susceptibility of Brachyspira hyodysenteriae strains isolated in Japan from 1985 to 2009. J Vet Med Sci 2010; 72:1651-3. [PMID: 20697185 DOI: 10.1292/jvms.10-0271] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The antimicrobial susceptibilities of 72 Brachyspira hyodysenteriae isolates collected from clinical cases of swine dysentery (SD) in 11 prefectures in Japan between 1985 and 2009 were investigated by an agar dilution method using five antimicrobial agents. There is a tendency of Japanese field isolates of B. hyodysenteriae to acquire resistance to the main antimicrobials used in SD treatment such as tiamulin, valnemulin, and efrotomycin. A responsible approach for selection and use of antimicrobial agents is required for SD treatment.
Collapse
Affiliation(s)
- Tatsuo Ohya
- Kyushu Research Station, Environmental/Enzootic Diseases Research Team, National Institute of Animal Health, Kagoshima, Japan.
| | | |
Collapse
|
37
|
Pati A, Sikorski J, Gronow S, Munk C, Lapidus A, Copeland A, Glavina Del Tio T, Nolan M, Lucas S, Chen F, Tice H, Cheng JF, Han C, Detter JC, Bruce D, Tapia R, Goodwin L, Pitluck S, Liolios K, Ivanova N, Mavromatis K, Mikhailova N, Chen A, Palaniappan K, Land M, Hauser L, Chang YJ, Jeffries CD, Spring S, Rohde M, Göker M, Bristow J, Eisen JA, Markowitz V, Hugenholtz P, Kyrpides NC, Klenk HP. Complete genome sequence of Brachyspira murdochii type strain (56-150). Stand Genomic Sci 2010; 2:260-9. [PMID: 21304710 PMCID: PMC3035287 DOI: 10.4056/sigs.831993] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Brachyspira murdochii Stanton et al. 1992 is a non-pathogenic, host-associated spirochete of the family Brachyspiraceae. Initially isolated from the intestinal content of a healthy swine, the ‘group B spirochaetes’ were first described as Serpulina murdochii. Members of the family Brachyspiraceae are of great phylogenetic interest because of the extremely isolated location of this family within the phylum ‘Spirochaetes’. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a type strain of a member of the family Brachyspiraceae and only the second genome sequence from a member of the genus Brachyspira. The 3,241,804 bp long genome with its 2,893 protein-coding and 40 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
Collapse
|
38
|
YANO T, MOE KK, CHUMA T, MISAWA N. Antimicrobial Susceptibility of Treponema phagedenis-Like Spirochetes Isolated from Dairy Cattle with Papillomatous Digital Dermatitis Lesions in Japan. J Vet Med Sci 2010; 72:379-82. [DOI: 10.1292/jvms.09-0418] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Takahisa YANO
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki
| | - Kyaw Kyaw MOE
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki
| | - Takehisa CHUMA
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, Kagoshima University
| | - Naoaki MISAWA
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki
- Project for Zoonoses Education and Research, University of Miyazaki
| |
Collapse
|
39
|
Pitucha M, Mazur L, Kosikowska U, Pachuta-Stec A, Malm A, Popiołek Ł, Rza̧czyńska Z. Synthesis, structure, and antibacterial evaluation of new N-substituted-3-amino- 5-oxo-4-phenyl-2,5-dihydro-1 H-pyrazole-1-carbothioamides. HETEROATOM CHEMISTRY 2010. [DOI: 10.1002/hc.20598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
40
|
Bernardeau M, Gueguen M, Smith DGE, Corona-Barrera E, Vernoux JP. In vitro antagonistic activities of Lactobacillus spp. against Brachyspira hyodysenteriae and Brachyspira pilosicoli. Vet Microbiol 2009; 138:184-90. [PMID: 19356863 DOI: 10.1016/j.vetmic.2009.03.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 03/04/2009] [Accepted: 03/06/2009] [Indexed: 11/24/2022]
Abstract
The sensitivity of Brachyspira hyodysenteriae and Brachyspira pilosicoli, respectively the causative agents of Swine Dysentery and Porcine Intestinal Spirochaetosis to two probiotic Lactobacillus strains, L. rhamnosus CNCM-I-3698 and L. farciminis CNCM-I-3699 was studied through viability, motility and coaggregation assays. The cell-free supernatant of these lactobacilli contains lactic acid, that is stressful for Brachyspira (leading to the formation of spherical bodies), and lethal. It was demonstrated for the first time the in vitro coaggregation properties of two probiotic Lactobacillus strains (active or heat-treated) with two pathogenic strains of Brachyspira, leading to (1) trapping of spirochaetal cells in a physical network as demonstrated by SEM; (2) inhibition of the motility of Brachyspira. Such in vitro studies should encourage in vivo studies in animal model to evaluate the potential of the use of probiotic lactobacilli through a feeding strategy for the prevention of B. hyodysenteriae and B. pilosicoli.
Collapse
Affiliation(s)
- Marion Bernardeau
- Unité de recherche des Microorganismes d'Intérêt Laitier et Alimentaire, IFR 146 ICORE, Université de Caen Basse-Normandie, Esplanade de la Paix, 14032 Caen, France
| | | | | | | | | |
Collapse
|
41
|
Hidalgo A, Carvajal A, García-Feliz C, Osorio J, Rubio P. Antimicrobial susceptibility testing of Spanish field isolates of Brachyspira hyodysenteriae. Res Vet Sci 2008; 87:7-12. [PMID: 19084246 DOI: 10.1016/j.rvsc.2008.10.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 10/30/2008] [Accepted: 10/31/2008] [Indexed: 10/21/2022]
Abstract
This study is the first conducted in Spain to evaluate antimicrobial susceptibility of field isolates of Brachyspira hyodysenteriae. One hundred and eight isolates of the bacterium, recovered from different Spanish swine farms between 2000 and 2007, were investigated. The minimum inhibitory concentrations (MIC) of erythromycin, tylosin, tiamulin, valnemulin, clindamycin and lincomycin were determined using a broth microdilution technique. Most of the isolates showed poor susceptibility to erythromycin (MIC(90)>256 microg/ml), tylosin (MIC(90)>256 microg/ml), clindamycin (MIC(90)>4 microg/ml) and lincomycin (MIC(90)=128 microg/ml). Reduced susceptibility to tiamulin and valnemulin was observed with a MIC>2 microg/ml in 17.6% and 7.41% of the B. hyodysenteriae isolates, respectively. Moreover, a survival analysis permitted the detection of an increasing trend in the MIC values for almost all the antimicrobials used in the treatment of swine dysentery when comparing recent isolates (from 2006 to 2007) with those recovered in earlier years (between 2000 and 2004).
Collapse
Affiliation(s)
- A Hidalgo
- Department of Animal Health (Infectious Diseases and Epidemiology), Veterinary Faculty, University of León, Spain.
| | | | | | | | | |
Collapse
|
42
|
Evans NJ, Brown JM, Demirkan I, Birtles R, Hart CA, Carter SD. In vitro susceptibility of bovine digital dermatitis associated spirochaetes to antimicrobial agents. Vet Microbiol 2008; 136:115-20. [PMID: 19081208 DOI: 10.1016/j.vetmic.2008.10.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 10/13/2008] [Accepted: 10/20/2008] [Indexed: 12/18/2022]
Abstract
Bovine digital dermatitis (BDD) is an infectious lameness in cattle, which has a large global impact in terms of animal welfare and cost. The majority of evidence suggests that spirochaetes are the aetiological agent of this disease. The aim of this study was to identify the susceptibility of BDD associated spirochaetes to a range of antimicrobial agents with a view to potential usage in vivo to treat this widespread cattle disease. A microdilution method was adapted to determine the in vitro susceptibilities of 19 UK digital dermatitis spirochaetes (6 Treponema medium/Treponema vincentii-like, 8 Treponema phagedenis-like and 5 Treponema denticola/Treponema putidum-like) to eight relevant antimicrobials. The BDD spirochaetes exhibited the highest susceptibility to penicillin and erythromycin and this information may now be used to aid development of efficacious treatments. This study has also identified that BDD spirochaete T167 is spectinomycin resistant and that the likely biological basis is a point mutation in the 16S rRNA gene. Interestingly, nearly all Brachyspira isolate 16S rRNA gene sequences in Genbank have this substitution, suggesting it may be responsible for the characteristic spectinomycin resistance reported for the Brachyspira genus.
Collapse
Affiliation(s)
- Nicholas J Evans
- Department of Veterinary Pathology, University of Liverpool, Liverpool L69 CBX, UK.
| | | | | | | | | | | |
Collapse
|
43
|
Pringle M, Bergsten C, Fernström LL, Höök H, Johansson KE. Isolation and characterization of Treponema phagedenis-like spirochetes from digital dermatitis lesions in Swedish dairy cattle. Acta Vet Scand 2008; 50:40. [PMID: 18937826 PMCID: PMC2576277 DOI: 10.1186/1751-0147-50-40] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Accepted: 10/20/2008] [Indexed: 11/10/2022] Open
Abstract
Background Digital dermatitis in cattle is an emerging infectious disease. Ulcerative lesions are typically located on the plantar skin between the heel bulbs and adjacent to the coronet. Spirochetes of the genus Treponema are found in high numbers in the lesions and are likely to be involved in the pathogenesis. The aim of this study was to obtain pure cultures of spirochetes from cattle with digital dermatitis and to describe them further. Methods Tissue samples and swabs from active digital dermatitis lesions were used for culturing. Pure isolates were subjected to, molecular typing through 16S rRNA gene sequencing, pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and an intergenic spacer PCR developed for Treponema spp. as well as API-ZYM and antimicrobial susceptibility tests. The antimicrobial agents used were tiamulin, valnemulin, tylosin, aivlosin, lincomycin and doxycycline. Results Seven spirochete isolates from five herds were obtained. Both 16S rRNA gene sequences, which were identical except for three polymorphic nucleotide positions, and the intergenic spacer PCR indicated that all isolates were of one yet unnamed species, most closely related to Treponema phagedenis. The enzymatic profile and antimicrobial susceptibility pattern were also similar for all isolates. However it was possible to separate the isolates through their PFGE and RAPD banding pattern. Conclusion This is the first report on isolation of a Treponema sp. from cattle with digital dermatitis in Scandinavia. The phylotype isolated has previously been cultured from samples from cattle in the USA and the UK and is closely related to T. phagedenis. While very similar, the isolates in this study were possible to differentiate through PFGE and RAPD indicating that these methods are suitable for subtyping of this phylotype. No antimicrobial resistance could be detected among the tested isolates.
Collapse
|
44
|
Råsbäck T, Jansson DS, Johansson KE, Fellström C. A novel enteropathogenic, strongly haemolytic spirochaete isolated from pig and mallard, provisionally designated ?Brachyspira suanatina? sp. nov. Environ Microbiol 2007; 9:983-91. [PMID: 17359270 DOI: 10.1111/j.1462-2920.2006.01220.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atypical, strongly haemolytic porcine isolates of intestinal spirochaetes differing genetically from Brachyspira hyodysenteriae were identified and characterized. The isolates were subjected to culture and biochemical tests, antimicrobial susceptibility testing and molecular analyses. None of four species-specific polymerase chain reaction systems targeting genes of B. hyodysenteriae gave a positive reaction. All the atypical porcine isolates were identical in their partial 16S rRNA and nox gene sequences with a previously described isolate from a mallard (Anas platyrhynchos), and differed only slightly from another mallard isolate. All these isolates were distinctly different from all currently recognized Brachyspira species. A challenge study was carried out using recently weaned pigs. Clinical signs and macroscopic changes consistent with swine dysentery were seen both in pigs given the atypical porcine isolate and in control pigs given the reference strain of B. hyodysenteriae (B204(R)). Pigs given the genetically similar isolate from a mallard became colonized and diarrhoea was observed. This is the first study indicating that Brachyspira isolates from mallard can infect pigs and induce diarrhoea. We propose that this atypical spirochaete genotype should be regarded as a new species within the genus Brachyspira, and be provisionally designated 'Brachyspira suanatina' sp. nov.
Collapse
Affiliation(s)
- Thérése Råsbäck
- Department of Clinical Sciences, Swedish University of Agricultural Sciences (SLU), PO Box 7018, SE-750 07 Uppsala, Sweden.
| | | | | | | |
Collapse
|
45
|
Pringle M, Aarestrup FM, Bergsjø B, Fossi M, Jouy E, Landén A, Mevius D, Perry K, Teale C, Thomson J, Skrzypczak T, Veldman K, Franklin A. Quality-control ranges for antimicrobial susceptibility testing by broth dilution of the Brachyspira hyodysenteriae type strain (ATCC 27164T). Microb Drug Resist 2006; 12:219-21. [PMID: 17002550 DOI: 10.1089/mdr.2006.12.219] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
There are no approved standards for antimicrobial susceptibility testing of the fastidious spirochete Brachyspira hyodysenteriae. An interlaboratory study was performed to establish MIC quality control ranges for six antimicrobial agents for the type strain of B. hyodysenteriae using broth dilution. The results showed that B. hyodysenteriae B78T ATCC 27164T is a suitable quality control strain. This is a first step toward standardization of methods regarding this anaerobe.
Collapse
Affiliation(s)
- M Pringle
- National Veterinary Institute, Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Egervärn M, Lindmark H, Roos S, Huys G, Lindgren S. Effects of inoculum size and incubation time on broth microdilution susceptibility testing of lactic acid bacteria. Antimicrob Agents Chemother 2006; 51:394-6. [PMID: 17060527 PMCID: PMC1797673 DOI: 10.1128/aac.00637-06] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inoculum size and incubation time were varied during broth microdilution testing of the susceptibilities of 35 strains of lactic acid bacteria to six antibiotics. An increase in either parameter resulted in elevated MICs for all species. An inoculum of 3 x 10(5) CFU/ml is recommended to assess the antibiotic susceptibilities of these bacteria by using broth microdilution.
Collapse
Affiliation(s)
- Maria Egervärn
- Microbiology Division, National Food Administration, Box 622, SE-751 26 Uppsala, Sweden.
| | | | | | | | | |
Collapse
|
47
|
Råsbäck T, Fellström C, Gunnarsson A, Aspán A. Comparison of culture and biochemical tests with PCR for detection of Brachyspira hyodysenteriae and Brachyspira pilosicoli. J Microbiol Methods 2006; 66:347-53. [PMID: 16457900 DOI: 10.1016/j.mimet.2005.12.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 12/19/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
Traditional culture and biochemical tests (CBT) were compared with PCR for sensitivity and detection of Brachyspira hyodysenteriae and Brachyspira pilosicoli in seeded faeces and clinical samples from diarrhoeic pigs. A duplex PCR system was developed based on primers detecting the tlyA-gene of B. hyodysenteriae and the 16S rRNA-gene of B. pilosicoli. Sensitivities for the PCR system were determined on seeded faeces, using DNA that had been recovered from primary cultures or extracted directly from faeces. Compared to CBT, PCR applied to DNA extracted directly from faeces lowered the sensitivity by a factor of 1000 to 10,000. B. hyodysenteriae and B. pilosicoli detection was compared for CBT and PCR using 200 clinical samples. CBT detected more B. hyodysenteriae isolates in the clinical samples than PCR, but fewer B. pilosicoli positive samples. An atypical strongly haemolytic isolate was detected only by CBT.
Collapse
Affiliation(s)
- T Råsbäck
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, P.O. Box 7018, SE-750 07 Uppsala, Sweden.
| | | | | | | |
Collapse
|
48
|
Pringle M, Landén A, Franklin A. Tiamulin resistance in porcine Brachyspira pilosicoli isolates. Res Vet Sci 2006; 80:1-4. [PMID: 16253666 DOI: 10.1016/j.rvsc.2005.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Revised: 01/17/2005] [Accepted: 02/16/2005] [Indexed: 11/27/2022]
Abstract
There are few studies on antimicrobial susceptibility of Brachyspira pilosicoli, therefore this study was performed to investigate the situation among isolates from pigs. The tiamulin and tylosin susceptibility was determined by broth dilution for 93 and 86 porcine B. pilosicoli isolates, respectively. The isolates came from clinical samples taken in Swedish pig herds during the years 2002 and 2003. The tylosin minimal inhibitory concentration (MIC) was >16 microg/ml for 50% (n=43) of the isolates tested. A tiamulin MIC >2 microg/ml was obtained for 14% (n=13) of the isolates and these were also tested against doxycycline, salinomycin, valnemulin, lincomycin and aivlosin. For these isolates the susceptibility to salinomycin and doxycycline was high but the MICs for aivlosin varied. The relationship between the 13 tiamulin resistant isolates was analyzed by pulsed-field gel electrophoresis (PFGE). Among the 13 isolates 10 different PFGE patterns were identified.
Collapse
Affiliation(s)
- M Pringle
- Department of Antibiotics, National Veterinary Institute, SE-751 89 Uppsala, Sweden.
| | | | | |
Collapse
|
49
|
Råsbäck T, Fellström C, Bergsjø B, Cizek A, Collin K, Gunnarsson A, Jensen SM, Mars A, Thomson J, Vyt P, Pringle M. Assessment of diagnostics and antimicrobial susceptibility testing of Brachyspira species using a ring test. Vet Microbiol 2005; 109:229-43. [PMID: 15982833 DOI: 10.1016/j.vetmic.2005.05.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Revised: 04/29/2005] [Accepted: 05/09/2005] [Indexed: 10/25/2022]
Abstract
There is no ring test for quality assessment available in Europe for diagnostics and antimicrobial susceptibility testing of the fastidious, anaerobic bacteria of the genus Brachyspira. Therefore, an international ring test for Brachyspira spp. was performed once a year during 2002-2004. Two sets of coded samples were prepared and distributed on each occasion. One set comprised six swabs dipped in pig faeces spiked with Brachyspira spp. intended for diagnostics. The other set comprised two pure strains intended only for susceptibility testing. All methods used were in-house methods. The species used were Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira innocens, Brachyspira murdochii and Brachyspira intermedia. In most cases, the correct Brachyspira spp. were detected. However, the results showed that Brachyspira spp. could be difficult to identify, especially if two Brachyspira spp. were mixed or if the concentration of Brachyspira in faeces was low. Additionally, some laboratories reported Brachyspira growth in control samples that were not seeded with any spirochaetes. The lowest detection level was 10(2) bacteria/ml faeces for both B. hyodysenteriae and B. pilosicoli. The susceptibility tests performed showed that disc diffusion was not recommendable for Brachyspira spp. Extended antimicrobial dilution series gave most congruent results. The diversity of the results highlights the importance of ring tests for a high quality of diagnostics and antimicrobial susceptibility tests for Brachyspira spp. This is the first ring test described for Brachyspira spp.
Collapse
Affiliation(s)
- T Råsbäck
- Swedish University of Agricultural Sciences, SLU, P.O. Box 7018, SE-75007 Uppsala, Sweden.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Pringle M, Poehlsgaard J, Vester B, Long KS. Mutations in ribosomal protein L3 and 23S ribosomal RNA at the peptidyl transferase centre are associated with reduced susceptibility to tiamulin in Brachyspira spp. isolates. Mol Microbiol 2005; 54:1295-306. [PMID: 15554969 DOI: 10.1111/j.1365-2958.2004.04373.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pleuromutilin antibiotic tiamulin binds to the ribosomal peptidyl transferase centre. Three groups of Brachyspira spp. isolates with reduced tiamulin susceptibility were analysed to define resistance mechanisms to the drug. Mutations were identified in genes encoding ribosomal protein L3 and 23S rRNA at positions proximal to the peptidyl transferase centre. In two groups of laboratory-selected mutants, mutations were found at nucleotide positions 2032, 2055, 2447, 2499, 2504 and 2572 of 23S rRNA (Escherichia coli numbering) and at amino acid positions 148 and 149 of ribosomal protein L3 (Brachyspira pilosicoli numbering). In a third group of clinical B. hyodysenteriae isolates, only a single mutation at amino acid 148 of ribosomal protein L3 was detected. Chemical footprinting experiments show a reduced binding of tiamulin to ribosomal subunits from mutants with decreased susceptibility to the drug. This reduction in drug binding is likely the resistance mechanism for these strains. Hence, the identified mutations located near the tiamulin binding site are predicted to be responsible for the resistance phenotype. The positions of the mutated residues relative to the bound drug advocate a model where the mutations affect tiamulin binding indirectly through perturbation of nucleotide U2504.
Collapse
Affiliation(s)
- Märit Pringle
- Department of Antibiotics, National Veterinary Institute, SE-75189 Uppsala, Sweden
| | | | | | | |
Collapse
|