Estudio experimental de la eficacia de sustancias no antibióticas para la prevención y tratamiento de las infecciones asociadas a prótesis osteoarticulares producidas por "Staphylococcus spp"

Abstract

Bacterial infections associated with medical devices are a serious problem nowadays to generate biofilms as growth mode on these devices. These biofilms can be defined as a sessile microbial community consisting irreversibly adhered cells to a substrate and between them, embedded in an extracellular matrix produced by themselves and exhibiting an altered phenotype in terms of growth rate and gene transcription. This mode of growth in biofilms is what makes the bacteria contained in it, more resistant to antibiotic treatments. All this forces us to search for new antimicrobials, as well as the study of combinations of these, for eradicating these bacterial infections due to biofilm formation. In this work, we study the ability of traditional antibiotic molecules (rifampicin and vancomycin) and non-antibiotic substances inhibiting quorum sensing, such as farnesol, to inhibit the process of adhesion and formation of biofilms of Staphylococcus epidermidis and S. aureus. In addition, we analyzed a mucolytic, N-acetylcysteine, as a coadyuvant to traditional treatment. Farnesol was an effective inhibitor of initial adherence and biofilm formation by Staphylococcus spp. NAC association with rifampicin and farnesol got a synergic effect on growth and biofilm formation of Staphylococcus spp, respectively. Higher than CMI of the antimicrobial concentrations caused decrease of biomass and/or viability of mature biofilms of staphylococci.