Atividade da exposição de antimicrobianos utilizados no tratamento de exacerbações pulmonares causadas por Staphylococcus aureus resistente à meticilina em estágios planctônicos e em biofilme recuperados de pacientes com fibrose cística

Abstract

The presence of methylin-resistant Staphylococcus aureus (MRSA) recovered from respiratory secretions of patients with Cystic Fibrosis (CF) has increased significantly in the last decade. Being a subject of global concern, the study of bacterial resistance is of extreme importance for the medical/scientific community as the decrease in the susceptibility of strains to antimicrobials results in increased mortality in hospitals, prolonged and high costs of treatments for several infections. The main objective of this work was to evaluate the influence of growth in biofilm and planktonic states, determining the susceptibility to antimicrobials in strains recovered from chronic pulmonary infections of patients with Cystic Fibrosis. In this work we sought to evaluate the capacity of three antimicrobials used for the treatment of FC (Ciprofloxacin, Vancomycin and Trimethoprim-sulfamethoxazole) in penetrating the biofilm present in the thick mucus characteristic of CF lungs, comparing their action on bacteria in a planktonic state and defining which concentrations are effective in these two conditions. Added to this, we validated that bacteria growing in biofilms are more resistant to antimicrobial agents than those growing in a planktonic state. The conclusion of this study reinforces the growing concern about antimicrobial resistance in MRSA, especially in patients with CF. Our results demonstrated that bacteria in biofilms exhibit significantly greater resistance compared to bacteria in a planktonic state, highlighting the need for more effective therapeutic strategies that consider the penetration of antimicrobials into biofilms. These findings demonstrate the importance of continuing research into innovative methods to combat bacterial resistance in complex clinical settings.