Abnormal basement membrane structures of seminiferous tubules in infertile men.

Testicular biopsies from 60 patients with impaired fertility were investigated by electron microscopy for changes in the basement membrane of seminiferous tubules. Six different types of abnormal basement membrane structures (ABMS)--analogous to those of glomerular basement membrane disease--have been found to a variable extent in biopsies of 33 cases. The occurrence of ABMS correlated with the severity of tubular changes, and ABMS were absent in tubuli seminiferi with an intact germinal epithelium. Except for ABMS type 2, thought to represent immune complex deposits, the origin of ABMS is unknown. ABMS type 2 was present in 21 cases. Since similar deposits have been observed in rabbits developing immune complex orchitis after vasectomy, our findings indicate the occurrence of immune complex orchitis in infertile men.