Correlation between insulin-like peptide 3 and appendix testis length in congenital cryptorchidism.

AIM The appendix testis (AT) is a vestigial remnant of Muller's paramesonephric duct. Insulin-like 3 hormone (INSL3) is produced in the Leydig cells of the testis. We investigated the possible correlation between AT length and plasma INSL3 concentrations in patients with congenital cryptorchidism (CCO) and patients with hydrocele, who served as controls. METHODS A total of 40 patients with CCO and 34 patients with hydrocele and orthotopic testes were investigated. Sixteen patients presented high cryptorchidism and 24 low cryptorchidism. During surgery, AT was identified in 34 patients with CCO (high cryptorchidism:15, low cryptorchidism:19) and 28 controls. Plasma INSL3 levels were measured with a spectrophotometry enzyme immunoassay Elisa sandwich technique. RESULTS AT was present in 85.0% of the boys with CCO and 82.4% of the controls. A significant positive correlation was found between the AT length and INSL3 concentrations in CCO patients. CONCLUSIONS A longer AT may reflect better testicular function in boys with CCO, since it is correlated with higher INSL3 concentrations.