DAIR in treating late-phase infection after total knee arthroplasty using continuous local antibiotic perfusion therapy: A case series study

Abstract

Abstract Background: Antimicrobial agents are administered via intramedullary antibiotic perfusion (iMAP)/intrasoft tissue antibiotic perfusion (iSAP) to infected lesions to control osteoarticular and soft tissue infections. Continuous local antibiotic perfusion (CLAP) has been reported to be useful. This study aimed to investigate the outcomes of DAIR combined with CLAP for delayed infection after total knee arthroplasty performed at our hospital. Subjects and methods: Six patients (male; one case, female; five cases, mean age 79.5 years (70-94)) underwent CLAP for delayed infection after TKA at our hospital between July 2020 and June 2022. They were followable for at least one year after surgery. Seven months (17-219), with a mean follow-up of 24.3 months (12-36). In addition to direct debridement and insert exchange, systemic antimicrobial treatment and CLAP with gentamicin were performed. We investigated the organisms causing the inflammation, the duration of iMAP/iSAP implantation, the maximum daily dose of GM, the maximum GM blood concentration, and the presence or absence of GM-induced adverse events. Result: Two of six patients had a recurrence of infection at five weeks and five months after initial CLAP and required repeat CLAP treatment, but all patients were able to preserve their components. The organisms responsible for the flare-ups were MSSA in three cases; ESBL-producing E. coli, mixed MSSA and streptococcal infection, and Klebsiella pneumonia in one case each; and unknown pathogens in one case. CLAP therapy for all patients was administered eight times in 6 cases: iMAP, mean: 10.0 days (5-16); iSAP, mean: 19.3 days (15-28); GM dose, mean: 162.5 mg/day (80-240); and GM blood concentration, mean: 1.4 µg/mL (0.2-5.0). Adverse events included one case of reversible acute kidney injury during CLAP in a patient with recurrent infection. Summary: DAIR with CLAP for delayed post-TKA infection can be a useful treatment option to preserve components and allow the infection to subside, provided the implant is not markedly loosened.