Comparative analysis of 23 synovial fluid biomarkers for hip and knee periprosthetic joint infection detection

There is interest in novel synovial fluid biomarkers for the detection of periprosthetic joint infection (PJI). Here, we assessed the diagnostic accuracy of 23 simple or sophisticated synovial fluid biomarkers for periprosthetic hip or knee infection detection. One hundred seven subjects were studied, 57 of whom had aseptic failure (AF) and 50 PJI. The following synovial fluid biomarkers were tested using spectrophotometric assays, immunoassays, lateral flow tests, or test strips: leukocyte count, monocyte percentage, lymphocyte percentage, neutrophil percentage, C‐reactive protein (CRP), glucose, lactate, granulocyte‐macrophage colony‐stimulating factor, interferon‐γ, interleukin‐1β (IL‐1β), IL‐2, IL‐4, IL‐5, IL‐6, IL‐8, IL‐10, IL‐12p70, IL‐13, IL‐17A, IL‐23, tumor necrosis factor‐α, α‐defensin, and leukocyte esterase. The best‐performing synovial fluid biomarkers to differentiate PJI from AF—that is, those with highest area under the curve compared to all other biomarkers—were leukocyte count, percent neutrophils and percent monocytes, CRP, and α‐defensin (P < .0001).