Abstract
Aim
Diagnosing periprosthetic joint infections (PJI) can be very challenging, especially infections caused by low virulence microorganisms. No single test with a 100% accuracy is available yet. Hence, different infection definitions were introduced to improve the diagnostic confidence and quality of research articles. Due to constant developments in this field, infection definitions are adopted continuously. The aim of our study was to find the most sensitive currently available infection definition among three currently used criteria (International Consensus Meeting – criteria 2018 (ICM), Infectious Diseases Society of America - criteria 2013 (IDSA), and European Bone and Joint Infection Society – criteria 2021 (EBJIS)) for the diagnosis of PJI.
Method
Between 2015 and 2020, patients with an indicated revision surgery due to septic or aseptic failure after a total hip or knee replacement were included in this retrospective analysis of prospectively collected data. A standardized diagnostic workup was done in all patients. The components of the IDSA-, ICM-, and EBJIS- criteria for the diagnosis of PJI were identified in each patient.
Results
Overall, 206 patients (hip: n=104 (50%); knee: n=102 (50%)) with a median age of 74 years (IQR 65 – 80y) were included. 101 patients (49%) were diagnosed with PJI when using the EBJIS- criteria. Based on the IDSA- and ICM- criteria, 99 patients (48%, IDSA) and 86 patients (42%, ICM) were classified as septic. Based on all three criteria, 84 cases (41%) had an infection. 15 septic cases (n=15/206; 7%) were only identified by the IDSA- and EBJIS- criteria.
In 2 patients (n=2/206, 1%), an infection was present based on only the ICM and EBJIS criteria. No case was classified as infected by one infection definition alone.
A statistically significant higher number of inconclusive cases was observed when the ICM criteria (n=30/206; 15%) were used in comparison to the EBJIS criteria (likely infections: n=16/206; 8%) (Fisher's exact test, p=0.041). The EBJIS definition showed a better preoperative performance in comparison to the other two definitions (p<0.0001).
Conclusions
The most sensitive infection definition seems to be the novel EBJIS– criteria covering all infections diagnosed by the IDSA- and ICM-criteria without detecting any further infection. In addition, less inconclusive (infection likely) cases were detected by the EBJIS-criteria in comparison with the ICM-criteria reducing the so called ‘grey zone’ significantly which is of utmost importance in clinical routine.
