A Rare Case of Scedosporium boydii Prosthetic Joint Infection Following Unicompartmental Knee Arthroplasty: Diagnostic and Therapeutic Challenges

Background: Fungal prosthetic joint infections (PJIs) are rare, diagnostically challenging, and difficult to treat. This report presents the first documented case of Scedosporium boydii infection following unicompartmental knee arthroplasty (UKA), highlighting diagnostic and therapeutic strategies.Case Presentation: A 54-year-old male developed persistent left knee pain six months post-UKA, with normal inflammatory markers (CRP, ESR, IL-6) and repeatedly negative synovial fluid cultures. Imaging revealed lateral osteolysis. Arthroscopic exploration identified hypertrophic synovium with fungal hyphae, confirmed histopathologically. A one-stage revision arthroplasty was performed, followed by intravenous/intra-articular voriconazole (0.2g bid, 12 days) and oral voriconazole (0.2g bid, 6 weeks) with levofloxacin (0.5g qd, 6 weeks). At six-month follow-up, symptoms resolved, biomarkers normalized, and the prosthesis remained stable.