Furthermore, the alpha-defensin test had a higher sensitivity (100%; 95% CI, 88.4%–100.0%) in diagnosing PJI among patients on antibiotics when compared with the ESR (69.0% [95% CI, 49.17%–84.72%], p = 0.001), the CRP (79.3% [95% CI, 60.3%–92.0%], p = 0.009), the fluid PMN% (79.3% [95% CI, 60.3%–92.0%), p = 0.009), and fluid culture (70.0% [95% CI, 50.6%–85.3%], p = 0.001). Here, CRP is linked to juvenile polyposis syndrome.