•A broth dilution procedure for AST of Brachyspira species is described.•The broth dilution method was validated in a ring trial.•Intra- and inter-laboratory reproducibility was good.•New control ...strains are proposed.•Increased MIC corresponded to genomic data indicating decreased susceptibility.
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.
A selection of plasmid-mediated AmpC-producing Escherichia coli isolates carrying blaCMY-2 from Swedish broilers were characterized to establish their relatedness to and a possible overlap with human ...clinical E. coli isolates. The results showed diversity among the E. coli isolated from broilers, indicating that the spread in the population was not due to one strain. However, only one type of plasmid belonging to replicon type incK was identified. Furthermore, there were no indications of spread of blaCMY-2E. coli isolates from broilers to human clinical settings, although Swedish broilers may be a source of blaCMY-2 and/or the plasmid carrying blaCMY-2.
Pregnancy as an immunosuppressive condition and with the associated tendency for mucosal oedema can predis- pose women to acute rhinosinusitis. Our hypothesis was that pregnancy enhances ...opportunistic sinus infections.
We retrospectively collected data on pregnant women with acute rhinosinusitis treated at the Department of Otorhinolaryngology, Helsinki University Hospital, Finland in 2010-2015. Maxillary puncture was performed on all patients, and patients with purulent sinus secretions and bacterial culture were included in the study. Clinical data on patients and microbial findings of bacterial cultures were recorded and compared with those of non-pregnant controls.
Ninety-five pregnant patients and 91 controls were included. The bacterial cultures of pregnant patients revealed bac- terial growth more often than control patients’ specimens (78.9% vs. 54.9%). The most common bacterial findings (pregnant vs. control patients) were Streptococcus pneumoniae 43.2% vs. 20.9%, Haemophilus influenzae 22.1% vs. 16.5%, and Moraxella catar- rhalis 10.5% vs. 2.2%. S. pneumoniae was the most frequent finding in all trimesters, and the proportion of S. pneumoniae sinusitis was highest during the last trimester of pregnancy.
The pathogens of acute rhinosinusitis in pregnant patients are the same as in non-pregnant patients, however, the proportions differ; during pregnancy S. pneumoniae infection is more frequent.
Brachyspira hyodysenteriae is the causative agent of swine dysentery, a severe diarrhoeal disease in pigs. Few drugs are available to treat the disease, owing to both antimicrobial resistance and ...withdrawal of drugs authorized for use in pigs. Tiamulin is the drug of choice in many countries, but isolates with decreased susceptibility have recently been reported. The mechanism of tiamulin resistance in B. hyodysenteriae is not known and this facet is essential to understand the dissemination of the trait. To study the resistance epidemiology of B. hyodysenteriae, further characterization of a set of isolates from Germany (n = 16) and the UK (n = 6) with decreased susceptibility to tiamulin was performed. The relatedness between the isolates was studied by comparing PFGE patterns, and the in vitro susceptibility to five other antimicrobials (aivlosin, doxycycline, salinomycin, chloramphenicol and avilamycin) was also determined. For comparison of the antimicrobial-susceptibility pattern, Swedish (n = 20) and British (n = 4) tiamulin-susceptible isolates were tested. The German isolates represented several different PFGE patterns, indicating that tiamulin usage has been sufficient to select clones with decreased tiamulin susceptibility at different farms in Germany. The PFGE pattern for the six British isolates with decreased tiamulin susceptibility was identical to that of the German isolates, and they had a similar antimicrobial-susceptibility pattern, except for resistance to aivlosin, which was only found in a few German isolates. No other co-resistance with tiamulin was found.
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 μg/ml for 50% (
n
=
43) of the isolates tested. A tiamulin MIC >2 μg/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.
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.
Dissolved free amino acids (DFAA) and ammonium in the pore water of a coastal sediment at a water depth of 40 m were investigated monthly for more than a year, to improve knowledge on how the ...concentrations and distributions of these dissolved compounds varied during an annual cycle. Seasonal changes in adsorbed amino acids and ammonium were also studied and adsorption coefficients were calculated. Ammonium distribution in the pore water showed clear seasonal trends. In the warmer period (August and September) there were high concentrations in the pore water, and in winter the lowest concentrations were measured. Pore water concentrations of DFAA were in general low, but showed seasonal trends during the year. At the end of summer when the bottom water temperature reached its maximum (about 14°C), the concentrations of DFAA were also at their maxima. However, a response to the input of organic matter to the sediment was also observed as increased pore water DFAA concentrations. The seasonal response was not strong, which probably was due to several processes (e.g. adsorption, degradation and bacterial assimilation) removing DFAA and thereby preventing large pools of DFAA from being built up in the pore water. Adsorption of ammonium followed the concentration of dissolved ammonium in the pore water and there was neither a relation with input of organic matter nor with temperature in the bottom water. The adsorption coefficient (the dimensionless K) for ammonium was 1.07 ± 0.11 and did not vary during the year. The adsorption coefficients for amino acids, which were all higher than K for ammonium, did show seasonal trends and the periods with high concentrations of adsorbed amino acids were related not only to high concentrations of DFAA, but also to recent input of organic matter and probably also to the stimulation of bioturbation as a result of high temperature in the bottom water at the end of summer. The results demonstrated a seasonal variation in K of amino acids, but not ammonium, indicating that the processes controlling dissolved concentrations were substantially different for these compounds.
Through the means of Swedish relocation politics, the capital of Stockholm has been constructed as a governing centre with the ability of giving something to a periphery thought of as unable to ...survive on its own. The relationship between centre and periphery, furthermore, produces images of what kind of knowledge can be located to "central" or "peripheral" regions. In this article I research the move of a knowledge-intense government agency from Stockholm to Östersund, a smaller inland town in the north. The data were collected through an ethnographic case study of a government agency. I adopt a discourse theoretical approach that provides a clear ontology of identity and processes of identification. This enables research on how ideological images of places create geographical identity positions. The aim of this article is to explore how groups of professionals at the government agency identified with geographical identities dependent on whether they were seen as experts or generalists. In conclusion, identity positions became important for how the relocation was organized. The establishment of the two identity positions functioned to stabilize the social environment during the move, a time when many things at work seemed to be in turmoil. At the same time the positions worked to exclude other ways of identifying with (work)place, and in this way sustained asymmetrical relations of domination and subordination between centre and periphery.
Objectives
In Sweden the prevalence of Enterobacteriaceae with transferable resistance to extended-spectrum cephalosporins (ESCs) is low. However, in broilers ESC-resistant Escherichia coli is ...common, with a clear dominance of bla
CMY-2. Antimicrobials are rarely used in broiler production in Sweden and cephalosporins are never used. Introduction through imported breeding stock and subsequent vertical transmission of the bacteria through the production pyramid could be one explanation for this high prevalence.
Methods
To test this hypothesis, paper linings from imported flocks of grandparent animals were screened for the presence of ESC-resistant E. coli and a positive flock, together with its progeny, was followed longitudinally through the production pyramid using boot swabs. The relationship of isolated ESC-resistant E. coli was investigated using multiple-locus variable number tandem repeat analysis (MLVA).
Results
ESC-resistant E. coli carrying bla
CMY-2 was isolated from six out of eight imported flocks of grandparent animals. One clone of E. coli carrying bla
CMY-2 occurred in all levels of the production pyramid and in flocks of imported grandparent animals.
Conclusions
E. coli carrying bla
CMY-2 is frequently present among grandparent animals imported to Sweden for breeding purposes. The occurrence of one clone in all levels of the production pyramid indicates that its introduction through imported breeding stock and vertical transmission through the production pyramid could be one explanation for the high proportion of Swedish broilers colonized with ESC-resistant E. coli.
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