Intraarticular and serum vancomycin concentration added to acrylic cement

Abstract

Background. Vancomycin is the antibiotic of choice in therapy of orthopaedic implant infections caused by methicillin-resistant bacteria but its use poses a risk of toxicity, especially in patients with renal insufficiency. Addition of vancomycin to acrylic cement may cause systemic exposition to this drug eluting from cement to serum, which may require high-flux hemodialysis. Methods. A patient hemodialysed twice a week underwent implantation of a spacer due to methicillin-resistant S. epidermidis infection of knee prosthesis. The spacer was made of acrylic cement loaded with 0,55 g of gentamicin per 40 g of cement and 6 g of vancomycin into totally 120 g of cement. The measurements of vancomycin concentration in serum within 9 days and in intraarticular fluid within 2 days were performed. Results. Maximal intraarticular vancomycin concentration was reached 7 hours after surgery (120 μg/mL ) and was over Minimal Inhibitory Concentration for 47 hours. The serum concentration reached maximal value (2,6 μg/mL) 13 hours after implantation of spacer and was 2,3 μg/mL on 9-th postoperative day. Conclusion. This composition of acrylic cement spacer containing gentamicin and vancomycin was found therapeutically effective and not necessitating high-flux hemodialysis in a hemodialysed patient with chronic renal failure. © 2014 Versita and Springer-Verlag.