Purpose: Varicocele represents a frequent cause of male infertility. Early identification and treatment of varicocele during adolescence may reduce the risk of infertility. The relationship of varicocele and its effect on semen quality and healthy male reproduction has been investigated. However obtainement of semen samples in adolescents is a sensitive topic. Alternatively blood samples are easier to obtain compared to ejaculates. Therefore, serum biomarkers of spermatogenesis are of major interest for population studies. Inhibins are glycoproteins predominantly produced in the gonads. Inhibin B, composed of α and β subunits, is the phsiologiacally relevant form on inhibin in males. Both subunits are produced by Sertoli cells, regulated by FSH and unidentified factors related to germ cells. The aim of this study was to evaluate hormonal parameters in a group of adolescents with varicocele in order to identify prognostic factors for testicular damage.Patients and Methods: Twenty adolescents at Taner stage 4-5 with left varicocele were studied and compared with a control group of twenty healty adolescents. All patients underwent ultrasonographic testicular volumetry as well as hormonal evaluation of inhibin B, testosterone, baseline and gonadotropin-releasing hormone, follicle-stimulating hormone as well as luteinizing hormone. Statistical analysis was performed using Mann - Whitney U test with p value < 0,05 taken as statistical significant. The same tests of endocrine function and testicular volume were repeated 6 months surgery following. Statistical analysis was performed using the Wilcoxon signed rank test with p value < 0,05 taken as statistical significant.Results: Patients with varicocele showed reduced levels of inhibin B compared to controls and a significant reduction in the testicular volume on the affected side. The response of luteinizing hormone to gonadotropin-releasing hormone stimulation was significantly higher in the varicocele group compared to the control group. No statistically significant differences in basal FSH, LH, testosterone and the maximal response of FSH were identified between subjects with varicocele group and the control group. Furthermore a significant inverse relationship of inhibin B compared to follicle-stimulating hormone was noted.Inhibin B levels were significantly higher following surgery in the same population. The left testis volume showed a significant increase 6 months postoperatively. Baseline FSH levels were significantly higher after surgery compared to preoperative levels. No statistically significant differences in basal LH, testosterone and the maximal response of LH were found between subjects with varicocele before and after surgery. A postoperative decrease of luteinizing hormone maximal serum levels following gonadotropin releasing hormone stimulation was noted but it was not statistically significant. Furthermore inhibin B levels in varicocele patients after surgery positively correlated with bilateral testicular volume and the correlation coefficient of inhibin B compared with baseline FSH was negative and statistical significant.Conclusion: In the light of these findings inhibin B might be a useful diagnostic marker of testicular damage caused by varicocele in adolescents. Inhibin B values could assist in the selection of adolescents for surgical treatment in order to prevent future infertility problems in these subset of patients.All of these observations suggest that the deterioration of the testicular function in adolescents with varicocele is a progressive phenomenon that requires extensive work up follow up to indentify early signs of testicular dysfunction. Early identification and treatment of varicocele during adolescence may prevent further testicular damage and reduce the risk of infertility.
Effects of a Commercial Canine Gonadotropin Releasing Hormone Vaccination on Intact Male Llamas and Alpacas
