PRDX2 and varicocele: Recently, a study aimed to analyze the differential expression pattern between unilateral and bilateral varicoceles has shown that the lower expression of fibronectin (FN1) and suppressor of morphogenesis in the genitalia 1 (SMG1) in patients with bilateral varicocele may be regarded as possible biomarkers to differentiate unilateral from bilateral varicoceles [39].Furthermore, in this study, the main proteins, markers of the damage caused by OS in patients with bilateral varicocele, are aldose reductase, annexin 1, and peroxiredoxin 2.