INCREASED APOPTOSIS IN THE CONTRALATERAL TESTES OF PATIENTS WITH TESTICULAR TORSION AS A FACTOR FOR INFERTILITY

Purpose: Unilateral testicular torsion is common and leads to bilatera l testicular injury. Spermiography is abnormal in 70% of patients afte r testicular torsion. Histological changes:in the contralateral testis at the time of torsion have been previously interpreted as the conseq uence of a predisposing testicular pathology or a noxious effect of th e twisted testis. We hypothesized that increased apoptosis in the cont ralateral testis in unilateral testicular torsion is a consequence of a breakdown in the blood-testis barrier of the twisted testis, which m ay increase the risk of infertility. Materials and Methods: A total of 17 patients 14 to 34 years old (mean age plus or minus standard devia tion 20.7 +/- 6.1) underwent surgery to alleviate unilateral testicula r torsion. Mean time from the first symptoms of torsion to surgery was 4.2 +/- 3.0 hours (range 0.5 to 11). Bilateral testicular biopsy was performed in all patients, and apoptosis was analyzed by terminal deox ynucleotidyl transferase mediated S-deosyuridine triphosphate nick end labeling. Results: Compared with controls, the incidence of apoptosis was increased in the contralateral testes in all patients. Apoptosis occurred predominantly in spermatocytes, early and late spermatids, an d Sertoli's cells. In contrast, spermatogonia, peritubular connective tissue (fibroblasts and myofibroblasts) and endothelial cells seldom u nderwent apoptosis. Leydig cells were affected less often than spermat ocytes. The extent of apoptosis and necrotic changes within the twiste d testicle directly correlated with the duration of torsion. Conclusio ns: Extensive apoptosis is a phenomenon that occurs regularly in the g erminal epithelium of the contralateral testis in testicular torsion. Specifically primary and secondary spermatocytes are predominantly aff ected. Notably spermatogonia, capillary endothelium, connective tissue and peritubular fibroblasts are rarely involved. A selection strategy has seemingly evolved that precludes the possibility of the perpetuat ion of genetic mutations, We hypothesize that trauma to the blood-test is barrier initiated by testicular torsion induces the release of apop totic activating factors (cytokines), which subsequently cause extensi ve apoptosis in the germinal epithelium of the contralateral testis. T herefore, it is probable that repeat apoptotic episodes may explain th e high incidence of infertility in these patients.