Synovial Fluid α-Defensin as a Biomarker for Peri-Prosthetic Joint Infection: A Systematic Review and Meta-Analysis

Background: Total joint arthroplasty (TJA) has been one of the most beneficial interventions for treating patients suffering from joint disorders. However, peri-prosthetic joint infection (PJI) is a serious complication that often accompanies TJA and the diagnosis of PJI is remains difficult. Questions remain regarding whether certain biomarkers can be valuable in the diagnosis of PJI. Patients and Methods: We conducted our systematic review by searching PubMed, Embase, Web of Science, the Cochrane Library, and Science Direct with the key words “periprosthetic joint infection,” “synovial fluid,” and “α-defensin.” Studies that provided sufficient data to construct 2 × 2 contingency tables were chosen based on inclusion and exclusion criteria. The quality of included studies was assessed according to the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for the included studies. The summary receiver operating characteristic (SROC) curve and the area under the summary receiver operating characteristic (AUSROC) were used to evaluate the overall diagnostic performance. Results: Eight studies were included in this systematic review. Among them four articles were included in meta-analysis. A total of 421 participants were studied in the meta-analysis. The pooled sensitivity, specificity, and DOR were 0.98 (95% confidence interval [CI]: 0.94–1.00), 0.97 (95% CI: 0.95–0.99), and 1095.49 (95% CI: 283.68.58–4230.45), respectively. The AUSROC was 0.9949 (standard error [SE] 0.0095). Conclusion: Synovial fluid α-defensin is a biomarker of high sensitivity and specificity for the diagnosis of PJI.