Shinsuke Ikeda1, Katsufumi Uchiyama2, Yojiro Minegishi3, Masaki Nakamura4, Masashi Takaso2. 1. Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan. ikedas@kitasato-u.ac.jp. 2. Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan. 3. Department of Orthopaedic Surgery, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama, 364-8501, Japan. 4. Department of Microbiology, Kitasato University School of Allied Health Sciences, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0373, Japan.
Abstract
PURPOSE: There is no single biomarker that can perfectly diagnose periprosthetic joint infection (PJI). As diagnosing PJI remains a major challenge, accurate and rapid development of a biomarker is required. Myeloperoxidase (MPO) is a bactericidal enzyme that acts against pathogenic microorganisms, such as those found in PJI. We aimed to determine whether elevated MPO levels could be detected in infected synovial fluid and to evaluate its utility as a biomarker for diagnosing chronic PJI. METHODS: Patients who underwent revision total joint arthroplasty were categorised into two groups according to the criteria of the second International Consensus Meeting on Musculoskeletal Infection: chronic PJI or aseptic failure. MPO was measured in synovial fluid collected during surgery. Receiver operating characteristic curves were drawn, and the area under the curve, 95% confidence intervals, and sensitivity/specificity were calculated. RESULTS: Synovial fluid was obtained from 37 patients. Nineteen patients were categorised into the chronic PJI group and 18 in the aseptic failure group. MPO levels in the synovial fluid were significantly higher in the chronic PJI group than in the aseptic failure group (p < 0.001). This measurement demonstrated the diagnostic accuracy of MPO for diagnosing chronic PJI with high sensitivity and specificity. CONCLUSION: Although the results are debatable owing to the small sample size, measurement of MPO demonstrates high accuracy as a biomarker for diagnosing chronic PJI, and it may detect culture-negative chronic PJI. Furthermore, MPO can measure host response to chronic PJI without the potential of contamination.
PURPOSE: There is no single biomarker that can perfectly diagnose periprosthetic joint infection (PJI). As diagnosing PJI remains a major challenge, accurate and rapid development of a biomarker is required. Myeloperoxidase (MPO) is a bactericidal enzyme that acts against pathogenic microorganisms, such as those found in PJI. We aimed to determine whether elevated MPO levels could be detected in infected synovial fluid and to evaluate its utility as a biomarker for diagnosing chronic PJI. METHODS: Patients who underwent revision total joint arthroplasty were categorised into two groups according to the criteria of the second International Consensus Meeting on Musculoskeletal Infection: chronic PJI or aseptic failure. MPO was measured in synovial fluid collected during surgery. Receiver operating characteristic curves were drawn, and the area under the curve, 95% confidence intervals, and sensitivity/specificity were calculated. RESULTS: Synovial fluid was obtained from 37 patients. Nineteen patients were categorised into the chronic PJI group and 18 in the aseptic failure group. MPO levels in the synovial fluid were significantly higher in the chronic PJI group than in the aseptic failure group (p < 0.001). This measurement demonstrated the diagnostic accuracy of MPO for diagnosing chronic PJI with high sensitivity and specificity. CONCLUSION: Although the results are debatable owing to the small sample size, measurement of MPO demonstrates high accuracy as a biomarker for diagnosing chronic PJI, and it may detect culture-negative chronic PJI. Furthermore, MPO can measure host response to chronic PJI without the potential of contamination.