Ultrastructural changes of corpora cavernosa in men with erectile dysfunction and chronic renal failure.

Erectile dysfunction (ED) is a common and often distressing side effect of renal failure. Uremic men of different ages report a high variety of sexual problems, including sexual hormonal pattern alterations, reduced or loss of libido, infertility, and impotence, thereby influencing their well-being. The pathogenic mechanisms include physiologic, psychologic, and organic causes. To determine the contribution of morphologic factors to impotence we studied the ultrastructure of the corpora cavernosa in 20 patients with end-stage renal disease who were treated with chronic dialysis and compared the findings with 6 individuals with no clinical history of impotence. Our results indicated that in male uremic patients with sexual disturbances there were major changes in smooth muscle cells. This was characterized by reduction of dense bodies in the cytoplasm, thick basement membranes, and increased interstitial collagen fibers with resultant reduction of cell-to-cell contact. In addition, there was thickening and lamination of basement membranes of endothelial cells and increased accumulation of collagen between nerve fibers. These alterations were more evident in patients with longer time on dialysis and were independent of type of primary renal disease. We hypothesize that ED in dialysis patients is not related to the primary disease but to the uremic state.