Cystic dilatation of the rete testis: a hidden diagnosis among infertile men

Cystic dilatation of the rete testis, often also known as cystic ectasia of the rete testis, is a poorly understood condition that may be a cause of male infertility. This study examined the frequency of this condition in 749 men attending an infertility clinic with their partners. Of these 749 men, semen analysis was abnormal in 275 (37%) but apparently normal in 474 (63%). All the men attending the infertility clinic underwent a testicular ultrasound. Of these 749 men, the lesion was present in nine (1.2%); it was present bilaterally in three and unilaterally in six. In two men, one of whom had a bilateral lesion, the sperm count was normal. It is unclear whether this lesion is a cause of infertility but it is important that this condition is diagnosed so that its prevalence and its relationship to infertility can be ascertained.