Abstract
Aim
Prompt recognition and identification of the causative microorganism in acute septic arthritis of native and prosthetic joints is vital to increase the chances of successful treatment. The aim of this study was to independently assess the diagnostic accuracy of the multiplex BIOFIRE® Joint Infection (JI) Panel (investigational use only) in synovial fluid for rapid diagnosis
Method
Synovial fluid samples were prospectively collected at the University Medical Center Groningen from patients who had a clinical suspicion of a native septic arthritis, early acute (post-operative, within 3 months after arthroplasty) periprosthetic joint infection (PJI) or late acute (hematogenous) PJI. JI Panel results were compared to culture-based methods as reference standard.
Results
A total of 45 samples were analyzed. The BIOFIRE JI Panel showed a high specificity (100%, 95% CI 73 – 100) and positive predictive value (100%, 95% CI 79 – 100) in all patient categories. Sensitivity and negative predictive value were 83% (95% CI 36 – 99) and 88% (95% CI 47 – 99) respectively for patients with a clinical suspicion of native septic arthritis (n=12), 77% (95% CI: 46 – 94) and 63% (95% CI: 26 – 90) for patients with a clinical suspicion of a late acute PJI (n=14), and 27% (95% CI 7 – 61) and 27% (95% CI: 7 – 61) for patients with a clinical suspicion of an early acute PJI (n=19).
Conclusions
The results of this pilot study indicate a clear clinical benefit of the BIOFIRE JI Panel in patients with a suspected native septic arthritis and late acute (hematogenous) PJI, but a low clinical benefit in patients with an early acute (post-operative) PJI due to the absence of low-grade microorganisms in the panel.