Fungal orthopaedic infections most commonly affect people with complex surgical histories and existing comorbidities. Recurrence and re-infection rates are high, even with optimal surgical and systemic antifungal treatment. AmBisome liposomal amphotericin B has been suggested for local antifungal therapy, as an adjunctive treatment for fungal osteoarticular infections. Few case series have examined its clinical use when combined with polymethylmethacrylate cement PMMA), or with absorbable local antibiotic carriers.
We aimed to evaluate the clinical use of local antifungal therapy with AmBisome liposomal amphotericin B (ABlaB), including tolerated doses, serious adverse events, and treatment outcomes.
A retrospective cohort of all patients treated with local antifungal therapy with ABlaB between January 2016 and January 2021 in a specialist orthopaedic hospital was identified using pharmacy records.
Renal function, serious adverse events during treatment, surgical outcomes including spacer fracture and infection recurrence, were identified from electronic clinical records. The project was approved by the Institutional Review Board (clinical audit 6871).
13 operations involving local antifungal therapy with ABlaB, in 12 patients, were identified. Eleven were infected with Candida species and one with Aspergillus. Mean follow-up was 22 months (range 4–46).
Ten first stage arthroplasty revisions, 2 second stage arthroplasty revisions, and one debridement and removal of metalwork for fracture-related infection were performed. Locally implanted doses of ABlaB ranged from 100mg to 3600mg (50–400mg per 40g mix of PMMA). Six patients received ABlaB in absorbable antibiotic carriers containing calcium sulphate. This was noted to delay carrier setting. Patients were also given systemic antifungal therapy.
No patients experienced serious adverse events related to toxicity from local antifungal therapy with ABlaB. There were no spacer fractures. Overall treatment success was 54% at final follow-up, although there were no recurrent fungal infections identified in patients experiencing treatment failure.
Local antifungal therapy with liposomal amphotericin B, when combined with surgery and systemic therapy, appears to be a safe and well tolerated intervention in the management of complex fungal osteoarticular infections.