Excluding infections in arthroplasty using leucocyte esterase test.

PURPOSE

Periprosthetic joint infections remain a major challenge for the surgeon in modern arthroplasty. The decision on how to handle a case is often difficult due to the variety of clinical presentations. The aim of this study was to establish the leucocyte esterase test as an intra-operative rapid diagnostic tool in an unclear infected or aseptic situation.

METHODS

In the setting of 364 endoprosthetic joint procedures on knee, hip and shoulder, we aspirated synovial fluid before performing capsulotomy. We performed a leucocyte esterase test. The results were correlated with the pre-operative synovial fluid aspirations, the laboratory blood sample parameters (C-reactive protein, white blood cells) and the intra-operative histopathological and microbiological findings.

RESULTS

The leucocyte esterase test has a sensitivity of 100% and a specificity of 96.5%. The positive predictive value was 82% and the negative predictive value was 100%. Correlation with conventional methods such as serum C-reactive protein and serum white blood cells is given. The histopathological evaluation confirmed the microbiological results in all but three cases.

CONCLUSIONS

Based on our results and the current literature, we recommend the leucocyte esterase test as a useful tool in the diagnosis of periprosthetic joint infection.