Ultrastructure of epididymal interstitial reactions following vasectomy and vasovasostomy

Abstract

The response of the male reproductive tract to vasectomy includes inflammation of the interstitial tissue of the epididymis. The pathogenesis of epididymal interstitial reactions and characteristics of the responding cells were studied by electron microscopy in Lewis rats at intervals following bilateral vasectomy, vasectomy followed 1 month later by vasovasostomy, or sham operations. In areas of interstitial reaction, numerous macrophages, monocytes, lymphocytes, neutrophils, and plasma cells occupied the connective tissue. Macrophages, containing many lysosomes and vesicles, aggregated and assumed the appearance of epithelioid cells. Processes of adjacent macrophages interdigitated with one another and closely approached the surfaces of lymphocytes. Many plasma cells with distended rough endoplasmic reticulum appeared in the interstitium. The majority of animals in the vasectomy and vasovasostomy groups exhibited epididymal interstitial changes by 2-3 months; the cauda epididymidis was the region most often affected. The ultrastructural features were indicative of chronic granulomatous inflammation and were consistent with an immune response that includes antigen presentation by macrophages to lymphocytes, lymphocyte differentiation, and local antibody production by plasma cells. The nearly complete absence of sperm or recognizable parts thereof in the interstitial tissue in the areas of the reactions suggests that these lesions formed in response to soluble antigens leaking from the duct. Vasovasostomy was not effective in reversing or retarding epididymal inflammation at the intervals studied.

Microscopic Vasectomy Reversal 30 Years Later: A Summary of 4010 Cases by the Same Surgeon

“…The point is that when there is vas fluid that is not clear, and this fluid contains no sperm, that is an indication of irreversible epididymal damage. For such cases, vasoepididymostomy is warranted, and many studies have shown that the epididymal damage this represents is not reversed by vasovasostomy (Flickinger et al, 1993; Srivastava et al, 2000). For that reason, and with further substantiation by the data in this paper, we still recommend vasoepididymostomy when the vas fluid is not clear and contains no sperm.…”

Intravasal azoospermia: a surgical dilemma

“…Two distinct processes were identified after vasectomy in rats. First, a frank spermatic granuloma, a visible cyst‐like structure ranging from a few millimetres to 1 cm in diameter, containing a semisolid core of many spermatozoa in various stages of disintegration, surrounded by neutrophils, macrophages, epithelioid cells and an outer shell of fibrous connective tissue [17]. In contrast, an epididymal interstitial reaction may occur, with microscopic granulomatous inflammations that lack a central core of spermatozoa and are not discretely encapsulated.…”

“…In contrast, an epididymal interstitial reaction may occur, with microscopic granulomatous inflammations that lack a central core of spermatozoa and are not discretely encapsulated. Soluble sperm antigens or constituents of epididymal fluid that leak from the lumen of the epididymis into the surrounding connective tissue after vasectomy may be the inciting factor for the interstitial reaction [17]. Commonly, the interstitial lesions occur in the cauda epididymis, which becomes distended with numerous sperm and debris after vasectomy, and thus may be more prone to leakage [18].…”

Influence of reproductive tract obstruction on expression of epididymal proteins and their restoration after patency

“…It is interesting that the total integrated intensity and total spot area of autoradiograms of patency after 60 days obstruction seem to be even lower than those of the group of obstruction for 120 days, which may be caused by the deposit of the proteins, since some studies have reported that morphological evaluation did not show significant remodeling of the caput epididymidal epithelium after reproductive tract obstruction. 17 However, a consistent downward trend of epididymal proteins remained after vasovasostomy. We consider that the function of the epididymis continues to be altered or becomes worse after surgically successful vasovasostomy because of the injury caused by the two surgeries.…”