CRP and juvenile polyposis syndrome: As paper published by Yong et al. [12] and Alisina et al. [13] showed that serum D-Dimer is a promising serological marker for the diagnosis of PJI especially when 0.85 μg/L was determined as the optimal threshold value, so, we decided to compare the sensitivity and specificity of serum CRP (> 10 mg/L), ESR (> 30 mm/h) and D-Dimer (> 0.85 μg/L) in the diagnosis of PJI.