Prediction of Phenotypic Antimicrobial Resistance Profiles From Whole Genome Sequences of Non-typhoidal Salmonella enterica

Surveillance of antimicrobial resistance (AMR) in non-typhoidal Salmonella enterica (NTS), is essential for monitoring transmission of resistance from the food chain to humans, and for establishing effective treatment protocols. We evaluated the prediction of phenotypic resistance in NTS from genotypic profiles derived from whole genome sequencing (WGS). Genes and chromosomal mutations responsible for phenotypic resistance were sought in WGS data from 3,491 NTS isolates received by Public Health England’s Gastrointestinal Bacteria Reference Unit between April 2014 and March 2015. Inferred genotypic AMR profiles were compared with phenotypic susceptibilities determined for fifteen antimicrobials using EUCAST guidelines. Discrepancies between phenotypic and genotypic profiles for one or more antimicrobials were detected for 76 isolates (2.18%) although only 88/52,365 (0.17%) isolate/antimicrobial combinations were discordant. Of the discrepant results, the largest number were associated with streptomycin (67.05%, n = 59). Pan-susceptibility was observed in 2,190 isolates (62.73%). Overall, resistance to tetracyclines was most common (26.27% of isolates, n = 917) followed by sulphonamides (23.72%, n = 828) and ampicillin (21.43%, n = 748). Multidrug resistance (MDR), i.e., resistance to three or more antimicrobial classes, was detected in 848 isolates (24.29%) with resistance to ampicillin, streptomycin, sulphonamides and tetracyclines being the most common MDR profile (n = 231; 27.24%). For isolates with this profile, all but one were S. Typhimurium and 94.81% (n = 219) had the resistance determinants blaTEM-1, strA-strB, sul2 and tet(A). Extended-spectrum β-lactamase genes were identified in 41 isolates (1.17%) and multiple mutations in chromosomal genes associated with ciprofloxacin resistance in 82 isolates (2.35%). This study showed that WGS is suitable as a rapid means of determining AMR patterns of NTS for public health surveillance

Identification of dfrA14 in two distinct plasmids conferring trimethoprim resistance in Actinobacillus pleuropneumoniae

OBJECTIVES: The objective of this study was to determine the distribution and genetic basis of trimethoprim resistance in Actinobacillus pleuropneumoniae isolates from pigs in England. METHODS: Clinical isolates collected between 1998 and 2011 were tested for resistance to trimethoprim and sulphonamide. The genetic basis of trimethoprim resistance was determined by shotgun WGS analysis and the subsequent isolation and sequencing of plasmids. RESULTS: A total of 16 (out of 106) A. pleuropneumoniae isolates were resistant to both trimethoprim (MIC >32 mg/L) and sulfisoxazole (MIC ≥256 mg/L), and a further 32 were resistant only to sulfisoxazole (MIC ≥256 mg/L). Genome sequence data for the trimethoprim-resistant isolates revealed the presence of the dfrA14 dihydrofolate reductase gene. The distribution of plasmid sequences in multiple contigs suggested the presence of two distinct dfrA14-containing plasmids in different isolates, which was confirmed by plasmid isolation and sequencing. Both plasmids encoded mobilization genes, the sulphonamide resistance gene sul2, as well as dfrA14 inserted into strA, a streptomycin-resistance-associated gene, although the gene order differed between the two plasmids. One of the plasmids further encoded the strB streptomycin-resistance-associated gene. CONCLUSIONS: This is the first description of mobilizable plasmids conferring trimethoprim resistance in A. pleuropneumoniae and, to our knowledge, the first report of dfrA14 in any member of the Pasteurellaceae. The identification of dfrA14 conferring trimethoprim resistance in A. pleuropneumoniae isolates will facilitate PCR screens for resistance to this important antimicrobial

The competitive acylation and sulphonylation of amines

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Method Development For The Determination Of Sulphonamide Residues In Chicken By Liquid Chromatography Ion Trap Tandem Mass Spectrometry

Satu kaedah yang mudah, sensitif dan dipercayai untuk penentuan sisa lima sulfonamida A simple, sensitive and reliable method for the determination of five sulphonamide residue

Ambident properties of phosphoramidates and sulphonamides

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Assessing antimicrobial resistance occurrence in the Portuguese food system : poultry, pigs and derived food, 2014-2018

Research Areas: Public, Environmental & Occupational Health ; Infectious Diseases ; Veterinary SciencesAntimicrobial resistance (AMR) spread in the food system is a major threat to public and animal health. We describe AMR trends in zoonotic bacteria and identify risk factors associated with AMR occurrence in animals and derived food in Portugal. Data from the Portuguese AMR surveillance programme on food- producing ani-mals, 2014–2018, were used. AMR frequencies were calculated for Escherichia coli, Campylobacter and Salmonella in broilers, turkeys, pig populations and their derived food products. AMR-associated factors were studied for Salmonella isolates: popula-tion, sampling stage (farm, slaughterhouse and processing plant), sample type (en-vironmental, carcase and food), sampler (HACCP, industry, official and official and industry), sample context (control and eradication programmes and monitoring), year (2014–2018) and season. Logistic regression was applied to estimate crude odds ratio and adjusted odds ratio (aOR) with 95% confidence intervals (95% CI). The final models were obtained using a backward stepwise method. This study in-cluded 2,157 Escherichia coli, 561 Campylobacter and 1,071 Salmonella isolates. The highest prevalence estimates amongst tested antimicrobials for each bacterial spe-cies in 2014–2018 had the following ranges: (i) (fluoro)quinolones: E. coli: 8 4 % – 9 3 % , Campylobacter: 94%– 98%; (ii) tetracyclines: E. coli: 68%–91%, Campylobacter: 87%– 91%, Salmonella: 72%; (iii) penicillins: E. coli: 82%–100%; (iv) sulphonamides: E. coli: 68%– 82%. Compared with the reference categories for host (broiler), year (2014), season (winter) and sampler (HACCP own checks), resistance to at least one anti-microbial in Salmonella was significantly less likely in laying hens (aOR 0.28; 95% CI: 0.18– 0.42), 2016 (aOR 0.56; 95% CI: 0.33–0.93), 2017 (aOR 0.29; 95% CI: 0.17–0.51) and 2018 (aOR 0.35; 95% CI: 0.20–0.61), autumn (aOR 0.63; 95% CI: 0.40–0.97) and more likely to occur in broiler products (aOR 5.14; 95% CI: 2.61–10.54), pork products (aOR 6.84; 95% CI: 3.74–12.98) and official and industry combined sampling (aOR 2.16; 95% CI: 1.06–4.47). This study reveals a high prevalence of Salmonella resistance, especially during the summer and in post-farm stages of the Portuguese food system to nearly all antimicrobials and in the summer in farms to (fluoro)quinolones. Measures to tackle resistance are requiredinfo:eu-repo/semantics/acceptedVersio

Pathology and treatment of labyrinthitis

Inflammation of the Inner Ear may be, in its origin:Otogenous >> Non-specific or Specific: including Tuberculous or Syphilitic;Meningitic; Haematogenous; Traumatic;but of these the most common by far is the non-specific type secondary to acute and chronic middle-ear suppuration (Logan Turner and Praser 1928) and it is with this group that this review is mainly concerned.Labyrinthitis has been known for about 200 years although it was Galen (second century) who first applied the term labyrinth to the inner ear. Mention must be made of such pioneers as Duverney (1684) who described pus in the middle and inner ear, Leschevin (1763) who noted caries of the labyrinth and petrous that went on to meningitis and Scarpa (1772) who discovered the membranous labyrinth; but it was Itard (1821) who first associated vertigo and vomiting with aural disease, and Jansen (1893) who put our anatomicopathological knowledge on a sound basis, while the histological studies of Wittmaack (1904), Neumann (1907), Alexander (1910) and Scheibe (1912) broadened our concept of the disease and exposed some of its problems.As regards treatment there were originally two schools of thought.- The Conservative School (Wittmaack, Heine and others), the older, considered that most cases would heal if the injurious factor, especially in the middle ear, were removed, and that no drainage of the labyrinth itself would be necessary. With the methods of examination then known it was not possible to diagnose purulent labyrinthitis with certainty, but this stage passed with the publication of Barscny's great work on the caloric reaction of the ear, and the introduction of the noise-box, the rotating chair, and the caloric tests (1907).It was then thought that this would differentiate serous from purulent labyrinthitis, producing a more active method of precedure and giving rise to the Radical School of Vienna (Holmgren, Ruttin, Barany, Hinsberg, Neumann and others) whose teaching was that an early labyrinthectomy in t o purulent labyrinthitis would avert the ever threatening meningitis. However surgical enthusiasm carried them too far, and soon operation was advised in f orms of labyrinthitis where less active treatment had formerly given good results, opinions which aroused opposition especially when it was realised that even serous labyrinthitis could result in complete though temporary extinction of function.Thus came the Intermediate School of Lund who did not believe in labyrinth surgery unlessneningitiswas imminent, and held that early lumbar puncture would detect this soon enough for operation to be effective