# Analysis of failure causes and risk prediction of debridement, antibiotics, and implant retention (DAIR) for acute periprosthetic joint infection (PJI)

## TL;DR

This study identifies risk factors for failure of a treatment called DAIR for joint infections and creates a model to predict which patients are more likely to fail the treatment.

## Contribution

The study introduces a novel risk prediction model for DAIR failure in acute periprosthetic joint infection based on clinical and inflammatory markers.

## Key findings

- DAIR success rate was 85.6%, with failure associated with knee infection, acute hematogenous infection, and elevated inflammatory markers.
- Acute hematogenous infection, high preoperative CRP, and resistant pathogens were identified as independent risk factors for DAIR failure.
- A nomogram model based on these factors showed strong predictive performance for DAIR outcomes.

## Abstract

Debridement, antibiotics, and implant retention (DAIR) is the preferred treatment for acute periprosthetic joint infection (PJI), yet its failure rate remains high, and the influencing factors are not fully elucidated. This study aimed to investigate the causes of DAIR failure in acute PJI and construct a risk prediction model based on clinical characteristics, inflammatory markers, and microbiological data.

A retrospective analysis was conducted on 90 patients with acute PJI treated at our medical center between January 2008 and April 2024. All patients underwent standard DAIR treatment and were categorized into success (n = 77) and failure (n = 13) groups based on outcomes. Demographic data, infection characteristics, laboratory markers, microbiological results, and surgical details were collected. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors, and a nomogram prediction model was developed.

The overall success rate of DAIR was 85.6% (77/90). The failure group exhibited significantly higher rates of knee joint infection (84.6% vs. 50.6%, p=0.023), acute hematogenous infection (61.5% vs. 20.8%, p=0.005), preoperative peripheral White Blood Cell (WBC) (9.5×10^9/L vs. 8.2×10^9/L, p=0.043), CRP (79.6–4 mg/L vs. 42.4 mg/L, p<0.001), ESR (80.6 mm/h vs. 60.5 mm/h, p=0.002), synovial fluid WBC (35,300×10^6/L vs. 21,843×10^6/L, p=0.043), and synovial fluid polymorphonuclear leukocytes (PMNs) (91.7% vs. 83.8%, p<0.001) compared to the success group. Multivariate logistic regression identified acute hematogenous infection (OR 11.704, 95% CI 1.957–119.357, p=0.015), preoperative CRP (OR 1.022, 95% CI 1.009–1.040, p=0.003), synovial fluid PMN% (OR 1.196, 95% CI 1.039–1.454, p=0.039), and resistant pathogens (OR 0.107, 95% CI 0.010–0.665, p=0.032) as independent risk factors for DAIR failure. The nomogram model based on these factors demonstrated robust predictive performance.

DAIR failure is closely associated with hematogenous infection, the intensity of inflammatory response, and the presence of resistant pathogens. The proposed risk prediction model may aid clinical decision-making and optimize patient selection for DAIR.