Inhibition of bacterial adherence to vascular catheters by the antimicrobial peptide AP7121

Healthcare-associated bloodstream infections are the leading cause of morbidity and mortality in hospitalized patients. Vascular catheter-related infection is its main sou-rce. Gram-positive bacteria, mainly Staphylococcus spp., are the most prevalent etiological agents. Our aim was to assess the inhibitory activity of the AP7121 on the Staphylococcus aureus adherence in vascular catheters. The biofilm-producer strain S. aureus ATCC 35556 (SA) was used. MIC AP7121 for SA was performed using 20 mm segments of the vascular catheter (n = 3) were inoculated with 104 UFC center dot mL-1 of SA. Three different treatment schemes (A: simultaneous, B: previous, and C: following bacterial challenge) using 1 x MIC AP7121 were tested. Control groups were included in each scheme. The MICAP7121 was 0.48 mg/L. A reduction of 2log10 representing a decrease of 99 % of viable SA cells was achieved with schemes A and B. The post-challenge treatment with AP7121 (scheme C) produced a reduction of 1log10 representing a 90 % decrease of viable SA cells. The results observed in this work suggest an AP7121 fast-antimicrobial activity that could be beneficial to reduce bacterial adherence on medical devices such as vascular catheters.