Leydig cell function in adolescent boys with varicoceles.

The incidence of varicoceles in adolescent boys ranges from 5% to 19.5%. We studied five adolescent boys aged 17 to 20 years with visible left-sided varicoceles. All of them had public hair and testicular volumes between 20 to 25 mL and had achieved stage V of pubertal development. Serum gonadotropin response to the intravenous administration of 100 micrograms of gonadotropin-releasing hormone (GnRH) and testosterone response to the administration of 2,000 IU human chorionic gonadotropin (hCG) daily for 3 days before and 3 months after varicocelectomy were measured. Basal levels of both gonadotropins were in the pubertal range, and there was no significant difference between serum levels before and after varicocelectomy. Both gonadotropins, however, showed increased responses to the administration of GnRH (luteinizing hormone [LH]: basal, 12.0 +/- 5.1 mIU/mL; peak, 105.0 +/- 36.0 mIU/mL; follicle-stimulating hormone [FSH]: basal, 11.6 +/- 4.2 mIU/mL, peak, 60.0 +/- 18.0 mIU/ml) that decreased after varicocelectomy (LH: basal, 14.3 +/- 6.0 mIU/mL; peak, 58.6 +/- 12.0 mIU/mL; FSH: basal, 6.8 +/- 4.6 mIU/mL; peak, 38.0 +/- 8.1 mIU/mL). Serum testosterone response to hCG was also significantly improved by varicocelectomy (testosterone peak: before, 780 +/- 210 ng/dL; after, 1850 +/- 170 ng/dL). Testicular biopsy specimens showed no histologic abnormalities and normal spermatogenesis. Endocrine evaluation in adolescent boys with varicoceles could detect an early Leydig cell dysfunction that could be corrected by varicocelectomy.