TDK conference 2020

The widespread of antimicrobial resistance can be observed worldwide, therefore its significance is outstanding both in human and animal health, and its prevention is one of the main tasks of veterinarians and researchers. In our research we investigated the possibilities of optimizing the use of antibacterial agents, in which one of the cornerstones is the determination of pharmacokinetic parameters at the site of infection. In the recent study, we compared the different sampling methods of porcine synovial fluid and measured the florfenicol concentration of the obtained samples.

The synovial fluid required for the research was collected by two different sampling procedures. In the first case microdialysis was performed while in the second, synovial fluid was taken directly from the joints. During microdialysis, sampling was continuous with a rate of 2 µl/minute and it was collected in every hour, while blood samples were also collected in every hour to determine plasma concentrations. During direct sampling, synovial fluid was taken 1, 2, 3, 4, 6, 8, 10, 12 and 24 hours following drug administration and blood samples were also collected 10, 20, 30, 40, 50 minutes, and 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 24 hours after administration of florfenicol. Blood and synovial sampling preceded drug administration in both cases.

During microdilysis, samples were taken from the left knee joint, while during direct sampling, all samples were taken from a different joint. Florfenicol concentration of samples were determined by the combination of liquid chromatography and mass-spectroscopy. Analysis of collected data was performed using a pharmacokinetic software.

The results of the two methods were compared, and a pharmacokinetic / pharmacodynamic analysis was performed with the obtained pharmacokinetic parameters, and the minimal inhibitory concentration values found in literature of the four most common pathogens (Streptococcus suis, Haemophilus parasuis, Mycoplasma hyorhinis, Mycoplasma hyosynoviae) causing arthritis in swine populations, to determine if florfenicol is the right choice in case of arthritis caused by pathogens mentioned above.