High dose of vancomycin plus gentamicin incorporated acrylic bone cement decreased the elution of vancomycin

High dose of vancomycin plus gentamicin incorporated acrylic bone cement decreased the elution of vancomycin Tao Li,1,*, Lilan Fu,2,* Jian Wang,1 Zhanjun Shi11Department of Orthopedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, People’s Republic of China; 2Nanfang PET Center, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, People’s Republic of China*These authors contributed equally to this workPurpose: Low doses of vancomycin and gentamicin were commonly incorporated into acrylic bone cement (antibiotic-impregnated bone cement, AIBC) during revision arthroplasty. Previous studies showed that only a very small amount of antibiotics could be eluted from AIBC. Given the fact that a high dose of antibiotic would elute high concentration of antibiotic, this study investigated the influence of a high dose of dual-antibiotic loading on the properties of cement.Methods: A total of 8 groups of AIBC containing either gentamicin or vancomycin or both with different amounts of antibiotics (1 g, 2 g and 4 g) were tested on material properties, elution profiles, antibacterial activity and cytological toxicity.Results: A high dose of gentamicin and vancomycin AIBC (with 2 g gentamicin and 2 g vancomycin loaded) regiment showed acceptable compressive strength of 74.25±0.72 MPa. No cytotoxicity or antibacterial activity reduction was observed in any group tested in this study. The elution profiles indicated that incorporating 2 g vancomycin resulted in 4.77% (1049.57±3.74 μg) released after 28 days. However, after 2 g gentamicin was added, the vancomycin released was significantly reduced to 2.42% (532.24±1.77 μg) (p