Anti-biofilm activity of antibiotic-loaded Hylomate®

Introduction: Antibiotic envelopes are being developed for cardiac implantable electronic device (CIED) wrapping to reduce the risk of infections. Methods: Fifteen CIED infection-associated bacterial isolates of Staphylococcus aureus, Staphylococcus epidermidis and Cutibacterium acnes were used to assess in vitro biofilm formation on Hylomate® compared to titanium, silicone and polyurethane coupons pre-treated with vancomycin (400 µg/ml), bacitracin (1000 U/ml) or a combination of rifampin (80 µg/ml) plus minocycline (50 µg/ml). Scanning electron microscopy (SEM) was performed to visualize bacteria on Hylomate®. Results: There was significantly less (p < 0.05) S. aureus and S. epidermidis on Hylomate® pre-treated with vancomycin, bacitracin or rifampin plus minocycline after 24 h of incubation (≤1.00 log₁₀ CFU/cm²) compared with titanium, silicone or polyurethane pre-treated with vancomycin, bacitracin or rifampin plus minocycline. C. acnes biofilms were not detected (≤1.00 log₁₀ CFU/cm²) on pre-treated Hylomate® coupons. Conclusions: This study showed that Hylomate® coupons pre-treated with antibiotics reduced staphylococcal and C. acnes biofilm formation in vitro.