Session Type: ePosters
Session Title: ePosters
Authors(s): J. Cieslinski, V.S.T. Ribeiro, M.A. Pedroni, A.P. De Andrade, L. Kraft, P.H. Suss, F. Tuon
Authors Affiliations(s): Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, 80215-901, Brazil, Brazil
Third Party Affiliation: Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil, 80215-901
Background:
Polymethylmethacrylate (PMMA) bone cement is commonly used for the fixation of joint prostheses, and supplemented with antibiotics it can also be applied in treatments of musculoskeletal infections. Vancomycin and gentamycin can present a synergic effect in some isolates of Staphylococcus aureus, but this synergic activity was not previously evaluated in antibiotic-loaded PMMA using a combination of fixed gentamycin dose and vancomycin with different concentrations. The aim of this study was to evaluate different concentrations of vancomycin and/or gentamicin loaded PMMA against biofilm formation of S. aureus.
Methods:Biofilm production of S. aureus ATCC 25923 in PMMA loaded with different concentrations of vancomycin and gentamicin (only PMMA - Control; 1g, 2g and 4g of vancomycin - V1, V2, V4, 500mg of gentamicin + 1g, 2g or 4g of vancomycin - V1G, V2G, and V4G, 500mg of gentamicin alone - G) were evaluated by quantitative analysis of biofilm cells, Scanning Electron Microscopy (SEM), qualitative viability assay, Fourier-transform infrared spectroscopy (FTIR), and checkerboard assay for synergism of antibiotics. Statistical analysis was performed by Mann Whitney test. The difference in CFU/mL was significant when p <0.05
Results:All antibiotic-loaded PMMA presented a reduction in the number of CFU (p<0.05) in quantitative assay. The gentamycin loaded-PMMA inhibits the grown of sessile cells, independent of the vancomycin concentration (p < 0,001). The SEM analysis showed evident biofilm in raw PMMA, and in V1, V4, G, and V1G, while V2, V2G, and V4G did not showed biofilm structure. The viability assay demonstrated that biofilm was present and viable in the PMMA without antibiotics, G, V1, and V2. In the group V1G, the biofilm was not viable. In V4, V2G and V4G, there were few cells, suggesting the presence of a small amount of biofilm, suggesting that the cells are non-viable. The FTIR spectra showed no significant differences, and checkerboard of vancomycin and gentamicin showed synergism.
Conclusions:The effects against adherence and bacterial development in PMMA loaded with vancomycin and gentamicin were seen mainly in the group using the concentrations of vancomycin 4g + gentamicin 500mg. The synergic effect of vancomycin and gentamicin can also be applied with antibiotic-loaded cement.
Keyword(s): Infection, PMMA, Antibiotic-loadedCOI Other: We would like to thank Fundação Araucária and Associação Paranaense de Cultura (APC) (CP 10/2019).
Session Type: ePosters
Session Title: ePosters
Authors(s): J. Cieslinski, V.S.T. Ribeiro, M.A. Pedroni, A.P. De Andrade, L. Kraft, P.H. Suss, F. Tuon
Authors Affiliations(s): Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, 80215-901, Brazil, Brazil
Third Party Affiliation: Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil, 80215-901
Background:
Polymethylmethacrylate (PMMA) bone cement is commonly used for the fixation of joint prostheses, and supplemented with antibiotics it can also be applied in treatments of musculoskeletal infections. Vancomycin and gentamycin can present a synergic effect in some isolates of Staphylococcus aureus, but this synergic activity was not previously evaluated in antibiotic-loaded PMMA using a combination of fixed gentamycin dose and vancomycin with different concentrations. The aim of this study was to evaluate different concentrations of vancomycin and/or gentamicin loaded PMMA against biofilm formation of S. aureus.
Methods:Biofilm production of S. aureus ATCC 25923 in PMMA loaded with different concentrations of vancomycin and gentamicin (only PMMA - Control; 1g, 2g and 4g of vancomycin - V1, V2, V4, 500mg of gentamicin + 1g, 2g or 4g of vancomycin - V1G, V2G, and V4G, 500mg of gentamicin alone - G) were evaluated by quantitative analysis of biofilm cells, Scanning Electron Microscopy (SEM), qualitative viability assay, Fourier-transform infrared spectroscopy (FTIR), and checkerboard assay for synergism of antibiotics. Statistical analysis was performed by Mann Whitney test. The difference in CFU/mL was significant when p <0.05
Results:All antibiotic-loaded PMMA presented a reduction in the number of CFU (p<0.05) in quantitative assay. The gentamycin loaded-PMMA inhibits the grown of sessile cells, independent of the vancomycin concentration (p < 0,001). The SEM analysis showed evident biofilm in raw PMMA, and in V1, V4, G, and V1G, while V2, V2G, and V4G did not showed biofilm structure. The viability assay demonstrated that biofilm was present and viable in the PMMA without antibiotics, G, V1, and V2. In the group V1G, the biofilm was not viable. In V4, V2G and V4G, there were few cells, suggesting the presence of a small amount of biofilm, suggesting that the cells are non-viable. The FTIR spectra showed no significant differences, and checkerboard of vancomycin and gentamicin showed synergism.
Conclusions:The effects against adherence and bacterial development in PMMA loaded with vancomycin and gentamicin were seen mainly in the group using the concentrations of vancomycin 4g + gentamicin 500mg. The synergic effect of vancomycin and gentamicin can also be applied with antibiotic-loaded cement.
Keyword(s): Infection, PMMA, Antibiotic-loadedCOI Other: We would like to thank Fundação Araucária and Associação Paranaense de Cultura (APC) (CP 10/2019).