Timing and microbiological profile influence long-term outcomes after debridement, antibiotics, and implant retention (DAIR) in acute hip periprosthetic joint infection

INTRODUCTION: The strategy of debridement, antibiotics, and implant retention (DAIR) represents one of the main therapeutic modalities for acute periprosthetic joint infection (PJI). However, reported outcomes remain highly variable, with success rates ranging from 16 to 92%. This study aimed to evaluate long-term treatment failure-free survival and identify risk factors for treatment failure in patients with acute hip PJI treated with DAIR using time-to-event analytical methods. MATERIAL AND METHODS: This retrospective study evaluated the treatment failure rate in 115 patients treated with the DAIR strategy for acute PJI following primary or aseptic revision hip arthroplasty between 1999 and 2018. Potential predictors of treatment failure-free survival, including patient characteristics, infection microbiology, and surgical timing, were analyzed using univariate tests, Cox proportional hazards regression (hazard ratio HR), and Kaplan-Meier survival estimates. RESULTS: Among the 115 patients included, 56 were women and 59 were men; 48 were aged 75 years or younger and 67 were older than 75 years. In 88 cases, the infection occurred after primary arthroplasty, whereas 27 followed aseptic revision surgery. The mean follow-up was 7.1 years (SD 4.4). At five years, treatment failure occurred in 30.4% of cases. Procedures performed within seven days of diagnosis showed lower failure rates than those after the first week following diagnosis (27.5% vs 53.8%, p = 0.05; HR = 2.09, 95% CI 0.91-4.79). Failure was more frequent after revision arthroplasty compared with primary arthroplasty (48.1% vs 25%, p = 0.02; HR = 2.15, 95% CI 1.08-4.27) and in polymicrobial infections compared with monomicrobial infections (47.8% vs 24.5%, p = 0.04; HR = 2.32, 95% CI 1.13-4.77). No other variables showed a significant association with failure risk. CONCLUSION: Revision arthroplasty and polymicrobial infections were associated with higher failure rates after DAIR. Lower failure rates were observed among patients treated within seven days of diagnosis, although this finding should be interpreted with caution and warrants further investigation.