Fusarium Species Fungal Prosthetic Joint Infection of the Proximal Interphalangeal Joint After Silicone Arthroplasty: A Case Report.

Background: Prosthetic joint infection (PJI) following proximal interphalangeal joint (PIPJ) arthroplasty is rare, with most reported cases involving bacterial organisms. Fungal PJIs comprise <1% of all PJIs, with Fusarium species an exceptionally uncommon cause, particularly in the upper extremity.

Case presentation: A 60-year-old female with a history of rheumatoid arthritis on methotrexate and adalimumab underwent right long finger PIPJ silicone arthroplasty. She presented 12 weeks postoperatively with pain, swelling, and radiographic changes concerning for PJI despite normal inflammatory markers. Implant explantation with debridement was performed, and intraoperative cultures grew Fusarium species. Initial oral voriconazole was insufficient, necessitating readmission for intravenous liposomal amphotericin B and oral posaconazole. Thirty-nine days after completing her 6-month antifungal course, she underwent arthrodesis, which later failed, requiring revision with iliac crest autograft and dorsal plate fixation. At latest follow-up, she remained pain-free with radiographic union and no recurrent infection.

Conclusions: Based on available literature, this represents the first reported case of Fusarium PJI following silicone arthroplasty of the hand. This underscores the importance of maintaining suspicion for atypical pathogens in immunosuppressed hosts and highlights the complexities managing fungal infections in small joint arthroplasty.