ABSTRACT
OBJECTIVE: To describe the safe and successful use of daptomycin-impregnated polymethyl methacrylate (PMMA) bone cement in the treatment of a case of recurrent prosthetic joint infection in a patient with multiple antibiotic allergies and past colonization with multiply antibiotic-resistant organisms. CASE SUMMARY: A 79-year-old female had a history of chronic recurrent left prosthetic hip infection. The patient had confirmed allergies to multiple antibiotics and a past history of colonization with methicillin-resistant Staphylococcus aureus. At first-stage revision surgery, the infected prosthesis was removed and samples were sent for microbiologic culture. A spacer device was fashioned, with incorporation of daptomycin and gentamicin into the PMMA bone cement at a concentration of 5% w/w for each antibiotic. Systemic daptomycin and gentamicin were administered postoperatively for 14 days. Propionibacterium acnes was isolated from deep-tissue specimens. The patient made excellent postoperative progress and was discharged after 2 weeks. Second-stage revision surgery was performed at 6 months, with no signs of persistent infection. She remained well, pain free, and mobilizing independently 2 years later. DISCUSSION: Daptomycin, a cyclic lipopeptide antibiotic, is approved for systemic treatment of endocarditis and skin and soft tissue infections. In vitro data demonstrate acceptable drug elution from and tensile strength of daptomycin-impregnated PMMA bone cement; however, clinical data are lacking. In our patient's case, the cement formulation was well tolerated, with no adverse effects detected, and demonstrated adequate mechanical strength in vivo. Infection with P. acnes, an unusual pathogen, was successfully treated. Further clinical studies are required to assess the efficacy of daptomycin-impregnated cement in infection with more typical pathogens, such as S. aureus. CONCLUSIONS: Daptomycin impregnation of PMMA bone cement may be an option in cases in which patient or pathogen factors preclude use of routinely incorporated agents.