ESR1 and juvenile polyposis syndrome: These findings were corroborated by Shahi et al. in a multicenter study of 106 PJIs, who reported that the 30 cases treated with antibiotics before diagnostic workup had a similar median alpha-defensin level compared to the 76 untreated cases, suggesting that alpha-defensin was more sensitive than ESR, CRP, fluid PMN%, and fluid culture when screening for PJI in the setting of antibiotic use [69].