Effects of unilateral torsion of the spermatic cord on the contralateral testis in human and guinea pig.

The fine structure of the contralateral, so-called unaffected, testis of two of three patients with unilateral testicular torsion revealed varying degrees of abnormalities, apparently related to the time course of the condition. In one patient (H-87) with unilateral torsion of 16 days duration, the contralateral testis revealed various morphological abnormalities. These included abnormal nuclear condensation in spermatids, disappearance of the inner component of the basal lamina, degeneration of the germinal epithelium, and "intermixing" of germinal epithelial cells with peritubular components. In the other patient (H-109) with severe atrophy of one testis as a result of torsion, the contralateral testis revealed abnormalities which included spermatids with degenerating heads and tails within the Sertoli cell cytoplasm near the basal lamina and peritubular thickening accompanied by a greater than usual number of Leydig cells. In guinea pigs with experimentally induced unilateral torsion, abnormal spermatid development was seen in the contralateral testis of those animals in which the affected testis was severely damaged. Moreover, the Sertoli cells exhibited a high degree of phagocytic activity. Fewer abnormal spermatids in the spermatogonial compartment were found in the contralateral testis of the animals which had only moderately altered histology of the affected testis. No fine structural change was noted in the contralateral testis of control or sham operated animals or in those which displayed only minimal damage in the affected testis. This study suggests that unilateral torsion of the spermatic cord resulting in moderate to severe damage to the affected testis may be associated with morphological abnormalities in the contralateral testis.