Pristinamycin in the treatment of MSSA bone and joint infection

Objectives The aim of this study was to evaluate pristinamycin in the treatment of MSSA bone and joint infection (BJI).Patients and methods A retrospective, single-centre cohort study (2001-11) investigated outcome in adults receiving pristinamycin for MSSA BJI and pristinamycin-related adverse events (AEs).Results One hundred and two MSSA BJIs were assessed in 98 patients [chronic infection, 33.3%; and orthopaedic device-related infection (ODI), 67.6%]. Surgery was performed in 77.5% of total cases, and in all but three ODIs, associated with antibiotic therapy of a median total duration of 29.2 weeks. Pristinamycin was prescribed as a part of the initial intensive treatment phase (29.4%) and/or included in final maintenance therapy (83.3%) at a dose of 47.6 (45.5-52.6) mg/kg/day for 9.3 (1.4-20.4) weeks. AEs occurred in 13.3% of patients, consisting of gastrointestinal disorder (76.9%) or allergic reaction (23.1%), leading to treatment interruption in 11 cases. AEs were related to daily dose (OR, 2.733 for each 10 additional mg/kg/day; P=0.049). After a follow-up of 76.4 (29.6-146.9) weeks, the failure rate was 34.3%, associated with ODI (OR, 4.421; P=0.006), particularly when the implant was retained (OR, 4.217; P=0.007). In most patients, the pristinamycin companion drug was a fluoroquinolone (68.7%) or rifampicin (21.7%), without difference regarding outcome.Conclusions Pristinamycin is an effective, well-tolerated alternative therapeutic option in MSSA BJI, on condition that a daily dosage of 50 mg/kg is respected.