With the up-and-coming tests and the combinations of different tests, which had showed different sensitivities and specificities to diagnosis of PJI, we found that the combination of PMN%, CRP, and IL-6 had the highest sensitivity (79%), while the highest value of specificity was 100%; this result was the same as to the combinations of WBC + PMN%, WBC + PCT, PMN% + PCT, and WBC + PMN% + PCT, and there were no significant difference in sensitivity when we combined any five kinds of tests or more to together to diagnosis PJI, and this phenomenon did not exist in specificity. This evidence concerns the gene IL6 and juvenile polyposis syndrome.