Opportunities for early oral therapy for prosthetic hip and knee joint infections (PJI): clinical experience at a large health authority.

Objectives: We described the clinical outcomes and estimated cost savings from switching patients to early oral therapy from intravenous (IV) therapy for prosthetic joint infections (PJI) based on predefined criteria. Methods: Retrospective observational study in a large health authority consisting of 12 acute care hospitals in Canada. Patient demographics, microbiological and treatment data were collected for all patients with first episode of knee or hip PJI in 2022. Treatment failure rates, allergic or adverse reactions to IV or oral treatment, and hospital readmission rates were reported for those who met criteria for early switch to oral therapy. Results: Fifty-one patients were included. Thirty-seven patients (73%) had knee PJI, with debridement, antibiotics, and implant retention being the most common procedure. Sixteen patients (31%) had IV therapy for the entire duration of treatment, and the mean duration was 44 days. Twenty-three patients (45%) could have been switched to oral therapy. In practice however, only 3 patients (6%) were switched to oral therapy by day 7 following surgical source control. Five patients (22%) had clinical and/or microbiological failure 2 years postsurgery. Four patients (17%) and 6 patients (26%) developed an allergic or adverse reaction to IV and oral therapy, respectively. Five patients (22%) developed line complications. We estimated potential cost savings of almost $70,000 Canadian dollars with early oral therapy. Conclusion: Almost half of our PJI patients could have been switched to oral therapy within 7 days post-surgical source control. This study highlights a great opportunity for antimicrobial stewardship.