Evaluating the Link Between Postoperative Timing of Rifampicin Introduction and the Clinical and Microbiological Outcomes of Orthopedic Staphylococcal Implant Infections

Background/objectives: In staphylococcal implant infections, there is often discussion about the optimal postoperative timing of the introduction of rifampicin in the postoperative period with open wounds. Methods: We reviewed all adult patients with residual staphylococcal implant infections between January 2014 and May 2024. We analyzed the delay to rifampicin use in relation to therapeutic failures, infection recurrences, and development of ultimate rifampicin resistance. Results: Among 103 independent infection episodes, 47 (46%) contained the pathogen , and the remainder were different coagulase-negative staphylococci. The median number of surgical interventions was one, and the median duration of postsurgical systemic antibiotic treatment was 84 days (interquartile range (IQR), 42-84 d). The median daily dose of oral rifampicin was 900 mg, and the median delay in its introduction was 5 days (IQR, 3-8 d). Overall, 18% of patients experienced an adverse event related to rifampicin (mostly gastrointestinal), requiring treatment to be stopped. The incidences of clinical failures and of microbiologically identical recurrences were 27% and 10%, respectively. The risk of rifampin resistance among any new staphylococcal infection or colonization during a median follow-up of 1.9 years was 1%. In the multivariate Cox regression analysis, the delay in rifampicin administration, its dose, or its duration failed to alter outcomes. Conclusions: In our retrospective cohort of staphylococcal orthopedic implant infections, the timing of rifampicin introduction failed to alter clinical and microbiological outcomes.