Prognosis of unexpected positive intraoperative cultures in arthroplasty revision: A large multicenter cohort

The positive-intraoperative-cultures-type prosthetic joint infection (PIOC-PJI) is considered when surgical cultures yield microorganisms in presumed aseptic arthroplasty revisions. Herein we assess the risk factors for failure in the largest cohort of PIOC-PJI patients reported to date. A retrospective, observational, multicenter study was performed during 2007–2017. Surgeries leading to diagnose PIOC-PJI included only one-stage procedures with either complete or partial prosthesis revision. Failure was defined as recurrence caused by the same microorganism. 203 cases were included (age 72 years, 52% females). Coagulase-negative staphylococci (n = 125, 62%) was the main etiology, but some episodes were caused by virulent bacteria (n = 51, 25%). Prosthesis complete and partial revision was performed in 93 (46%) and 110 (54%) cases, respectively. After a median of 3.4 years, failure occurred in 17 episodes (8.4%, 95%CI 5.3–13.1). Partial revision was an independent predictor of failure (HR 3.63; 95%CI 1.03–12.8), adjusted for gram-negative bacilli (GNB) infection (HR 2.68; 95%CI 0.91–7.89) and chronic renal impairment (HR 2.40; 95%CI 0.90–6.44). Treatment with biofilm-active antibiotics (rifampin/fluoroquinolones) had a favorable impact on infections caused by staphylococci and GNB. Overall prognosis of PIOC-PJI is good, but close follow-up is required in cases of partial revision and in infections caused by GNB. •The overall prognosis of unsuspected positive intraoperative cultures (PIOC) is good.•Partial revision of the orthopedic device is the main risk factor for failure in PIOC.•Gram-negative bacilli infection worsens the prognosis in PIOC.•Biofilm-active antibiotics (rifampin and fluoroquinolones) may improve the prognosis.•This is the largest cohort of patients with PIOC reported to date.