Rates and Predictors of Treatment Failure in Staphylococcus aureus Prosthetic Joint Infections According to Different Management Strategies: A Multinational Cohort Study—The ARTHR-IS Study Group

Introduction Guidelines have improved the management of prosthetic joint infections (PJI). However, it is necessary to reassess the incidence and risk factors for treatment failure (TF) of Staphylococcus aureus PJI (SA-PJI) including functional loss, which has so far been neglected as an outcome. Methods A retrospective cohort study of SA-PJI was performed in 19 European hospitals between 2014 and 2016. The outcome variable was TF, including related mortality, clinical failure and functional loss both after the initial surgical procedure and after all procedures at 18 months. Predictors of TF were identified by logistic regression. Landmark analysis was used to avoid immortal time bias with rifampicin when debridement, antibiotics and implant retention (DAIR) was performed. Results One hundred twenty cases of SA-PJI were included. TF rates after the first and all surgical procedures performed were 32.8% and 24.2%, respectively. After all procedures, functional loss was 6.0% for DAIR and 17.2% for prosthesis removal. Variables independently associated with TF for the first procedure were Charlson ≥ 2, haemoglobin 30 kg/m 2 and delay of DAIR, while rifampicin use was protective. For all procedures, the variables associated with TF were haemoglobin