title: Elution of antibiotics from poly(methyl methacrylate) bone cement after extended implantation does not necessarily clear the infection despite susceptibility of the clinical isolates.
abstract: Chronic orthopedic infections are commonly caused by bacterial biofilms, which are recalcitrant to antibiotic treatment. In many cases, the revision procedure for periprosthetic joint infection or trauma cases includes the implantation of antibiotic-loaded bone cement to kill infecting bacteria via the elution of a strong local dose of antibiotic(s) at the site. While many studies have addressed the elution kinetics of both non-absorbable and absorbable bone cements both in vitro and in vivo, the potency of ALBC against pathogenic bacteria after extended implantation time is not clear. In this communication, we use two case studies, a Viridans streptococci infected total knee arthroplasty (TKA) and a MRSA-polymicrobial osteomyelitis of a distal tibial traumatic amputation (TA) to demonstrate that an antibiotic-loaded poly(methyl methacrylate) (ALPMMA) coated intermedullary rod implanted for 117 days (TKA) and three ALPMMA suture-strung beads implanted for 210 days (TA) retained killing ability against Pseudomonas aeruginosa and Staphylococcus aureus in vitro, despite different clinical efficacies. The TKA infection resolved and the patient progressed to an uneventful second stage. However, the TA infection only resolved after multiple rounds of debridement, IV vancomycin and removal of the PMMA beads and placement of vancomycin and tobramycin loaded calcium sulfate beads.
authors.affiliation: Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, OH 43210, USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Swearingen
authors.affiliation: Department of Orthopaedics, The Ohio State University, OH 43203, USA.
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Granger
authors.affiliation: Department of Orthopaedics, The Ohio State University, OH 43203, USA.
authors.forename: Anne
authors.initials: A
authors.lastname: Sullivan
authors.affiliation: Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, OH 43210, USA Department of Orthopaedics, The Ohio State University, OH 43203, USA paul.stoodley@osumc.edu.
authors.forename: Paul
authors.initials: P
authors.lastname: Stoodley
mesh_terms: D000328:Adult; D000368:Aged; D000673:Amputation, Traumatic / Q000150:complications; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics* / Q000494:pharmacology / Q000627:therapeutic use*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D001424:Bacterial Infections / Q000628:therapy*; D001843:Bone Cements / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D019904:Polymethyl Methacrylate / Q000627:therapeutic use*; D016459:Prosthesis-Related Infections / Q000628:therapy*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D001843:Bone Cements; D019904:Polymethyl Methacrylate
keywords: MRSA; MSSA; Pseudomonas; antibiotic-loaded poly(methyl methacrylate); biofilm; bone cement; chronic infection; elution; extended implantation; zone of inhibition