Abstract
Introduction
The intra-operative diagnosis of Prosthetic Joint Infection (PJI) is a dilemma requiring intra-operative sampling of suspicious tissues for frozen section, deep tissue culture and histopathology to secure a diagnosis. Alfa defensin-1 testing has been introduced as a quick and reliable test for confirming or ruling out PJI. This study aims to assess its intra-operative reliability compared to the standard tests.
Methods
Twenty patients who underwent revision hip and knee arthroplasty surgery were included. Patients joint aspirate was tested intra-operatively with the Synovasure kit, which takes approximately ten minutes for a result. Our standard protocol of collecting 5 deep tissue samples for culture and one sample for histopathology was followed. Results for Alfa defensin-1 test were then compared with final culture and histopathology results in all these patients.
Results
Our results show an excellent correlation with the final deep tissue cultures and histopathology outcomes. Literature reports frozen section to have low (58–73%) sensitivity but high (96%) specificity.
Conclusions
Alfa defensin-1 test is easy, quick and efficient; results were available immediately intra-operatively. Cryosection is time consuming with samples shipped to the reference laboratory at times resulting in intra-operative delays. In our practice Alfa defensin-1 test certainly will replace frozen section for intra-operative testing.