FOCAL ATROPHY OF THE SEMINIFEROUS TUBULE IN THE HUMAN TESTIS

Three types of focal atrophy of the seminiferous tubule, A, B and A+B type, were recognized in the 250 testes obtained from human subjects who died of acute death. The A-type consists of complete hyalinized scarring of the tubule and the B-type of varing degrees of tubular collapse. The A+B type shows combined atrophy of A and B-type in which B-type occurs peripherally to A-type occlusion in sequence and might be induced by local obstruction of luminal flow. Focal tubulitis is uncommon but has been observed in the A+B type atrophy which is characterized by sperm retention and the presence of sperm-phagocytic macrophages in the lumen. Areas around the rete testis and periseptal zones of the testis are preferential sites for tubular atrophy. B-type atrophy as an abortive form of A-type is predominant in the younger groups of the second to third decades, and the incidence of A-type increases after the fifth decade. It is suggested that A and B-type are brought about by locally limited ischemia in relation to circulatory disturbance with arteriolar hyalinosis which commonly appears focally in the postpuberal testis.