Predictors of treatment success following peri-prosthetic joint infection: 24-month follow up from a multi-center prospective observational cohort study of 653 patients

<jats:title>Abstract</jats:title> <jats:sec> <jats:title>Background</jats:title> <jats:p>Peri-prosthetic joint infection (PJI) is a devastating condition and there is a lack of evidence to guide its management. We hypothesised that treatment success is independently associated with modifiable variables in surgical and antibiotic management.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Prospective, observational study at 27 hospitals across Australia and New Zealand. Newly diagnosed large joint PJIs were eligible. Data were collected at baseline and at 3, 12 and 24 months. The main outcome measures at 24 months were clinical cure (defined as all of: alive, absence of clinical or microbiological evidence of infection and not requiring ongoing antibiotic therapy) and treatment success (clinical cure plus index prosthesis still in place).</jats:p> </jats:sec> <jats:sec> <jats:title>Findings</jats:title> <jats:p>24-month outcome data were available for 653 patients. Overall, 449 (69%) experienced clinical cure and 350 (54%) treatment success. The most common treatment strategy was debridement and implant retention, with success rates highest in early post-implant infections (119/160; 74%) and lower in late acute (132/267, 49%) and chronic (63/142, 44%) infections. Selected comorbidities, knee joint and S.aureus infections were independently associated with treatment failure, but antibiotic choice and duration (including rifampicin use) and extent of debridement were not.</jats:p> </jats:sec> <jats:sec> <jats:title>Interpretation</jats:title> <jats:p>Treatment success in PJI is associated with selecting the appropriate treatment strategy, and with non-modifiable patient and infection factors. Interdisciplinary decision-making which matches an individual patient to an appropriate management strategy is a critical step for PJI management. Randomised controlled trials are needed to determine the role of rifampicin in patients managed with DAIR and