Quantitative and ultrastructural study of germinal epithelium in testicular biopsies with "mixed atrophy".

In 17 cases of male sterility with so-called "mixed atrophy" in testicular biopsies, the germinal epithelium was investigated by quantitative as well as by ultrastructural means. In 13 cases, the number of spermatids only was reduced, in 2 cases earlier stages of germinal cells were diminished also. Normal quantitative data were found in biopsies of 2 patients. Among ultrastructural alterations various disturbances of the acrosome were dominant. Additional ultrastructural findings in spermatids included binucleate forms and lack of mitochondrial sheaths in the middle-piece. The largely uniform changes in the tunica propria (fibrosis of the innermost layers, extensive changes of the basement membrane) were considered to be at least one of the cofactors responsible for the alterations of the germinal epithelium.