[Cystic dysplasia of rete testis associated with ipsilateral renal agenesis. Case report].

Cystic dysplasia of the rete testis is a rare abnormality often associated with the ipsilateral agenesis of kidney. This malformation is due to a development defect of the mesonephric duct which is the cause of both the dilation of the testicular rete testis and renal agenesis. A case of this rare malformation, showing all the peculiarities described in the medical literature, is presented. A 3 years-4 months boy was examined for an asymptomatic left scrotal mass; thus, he underwent ultrasonography, which showed a multiple tubular and cystic dilatation of left rete testis, associated with the absence of left kidney, afterward confirmed by MAG3-radionuclide scan. Diagnosis was also validated by testicular biopsy. No surgery was required. The child is nowadays under observation and at 2-years follow-up he doesn't show any symptom. According to many authors, a conservative treatment of this benign congenital abnormality is suggested as well as serial ultrasonography to monitor the growth of the testicular mass, which in a longest follow-up, could require surgery. Malignant transformation nor infertility have never been described.