CRP and juvenile polyposis syndrome: The same trend was observed in the validation group. Haptoglobin levels were significantly higher in patients with PJI (227.08 ± 92.00 mg/dl vs. 119.72 ± 78.97 mg/dl, P < 0.001) and had a diagnostic efficacy comparable to CRP (AUC: 0.856 vs. 0.880).