Impact of Rifampicin in Treatment Outcome of Cutibacterium Acnes Prosthetic Joint Infections

Inclusion Criteria: * Age: \> or =18 years old; * Monomicrobial, rifampicin susceptible Cutibacterium acnes late total knee arthroplasty (TKA) or hip arthroplasty (total, THA or hemiarthroplasty, HH) or shoulder arthroplasty (total, TSA or hemiarthroplasty, SH) infection treated surgically with single-stage or two-stage revision; * Isolation of C. acnes on two distinct per-operative samples collected during the single-stage or the two-stage revision * Based on the antimicrobial susceptibility test of the C. acnes and the medical history of the patient, the PJI can be treated with amoxicillin or moxifloxacin; * Women considered of childbearing potential (WOCBP) requires use of a highly effective contraceptive measure as intrauterine device (IUD), intrauterine hormone-releasing system (IUS), documented bilateral tubal occlusion, documented vasectomised partner, sexual abstinence. Contraception should be maintained during treatment and until the end of relevant systemic exposure. Exclusion Criteria: * Contraindication to Rifampicin (included ongoing treatment contraindicated with rifampicin) * Contraindication to Amoxicillin AND moxifloxacin (included ongoing treatment contraindicated with these medicines) * Empirical antibiotic treatment not administered during the 24 hours following revision surgery; * Inactive empirical antibiotic treatment following surgery according to the AST of the bacteria; * disease-modifying treatment incompatible with the inducer effect of rifampicin * Liver cirrhosis; * Pregnancy: a pregnancy blood test will be performed on all women of childbearing age. The results will be sent to the patient by the doctor of their choice; * Porphyria; * Renal insufficiency with GFR \< 30ml/min/1.73 m2 (CKD-EPI);