INTRODUCTION: The management of prosthetic joint infection requires a complex treatment procedure and can be associated with complications. However, the occurrence of severe adverse events during this intervention has been poorly evaluated. PATIENTS AND METHODS: A 5-year multicentric retrospective study including patients from 3 hospitals in the South-Western France referral center for complex bone and joint infections (Crioac GSO) and treated for hip or knee prosthetic joint infection with 1 or 2-stage implant exchanges. The objective was to describe grade ≥ 3 adverse events, according to the CTCAE classification, occurring within 6 weeks after surgery and to identify their associated factors. RESULTS: 118 patients were identified. We observed 71 severe events in 50 patients (42.3 %; 95% confidence interval [CI95%]: 33.8-51.4%). Sixteen severe events were an evolution of the infection. The remaining 55 others (47 grade 3 and 8 grade 4) occurred in 41 patients (34.7%; CI95%: 26.8-43.7%). They were distributed as follows: 27 (49.1%) medical complications, 21 (38.2%) surgical complications and 7 (12.7%) antibiotic-related complications. The main identified risk factor was a two-stage prosthetic exchange with OR=3.6 (CI95% [1.11-11.94], p=0.032). Obesity was limit of significance with OR=3.3 (CI95 % [0.9-12.51], p=0.071). Infection with coagulase negative Staphylococcus was a protective factor with OR=0.3 (CI95% [0.12-0.99], p=0.047). CONCLUSION: Severe adverse events are frequent following prosthetic exchange for PJI (34.7%) and are related to the high frequency of comorbidities in this population and to the complex surgical procedures required. The risk factor significantly associated with these events was a two-stage exchange.Read less <