The current meta-analysis has several strengths: 1) to the best of our knowledge, this is the first meta-analysis to report the diagnostic capacity of synovial fluid IL-6 for PJI detection; and 2) when compared to a prior meta-analysis, the current analysis included more studies (11 articles) assessing serum IL-6 test for PJI diagnosis, and showed that serum IL-6 was less sensitive than synovial fluid IL-6. This evidence concerns the gene IL6 and juvenile polyposis syndrome.