EQUINE VETERINARY EDUCATION / AE / APRIL 2006 85

Case Report Bilateral epididymal nodules in a stallion M. A. POZOR* AND M. GARNCARZ† Department of Animal Reproduction, University of Agriculture, Al. Mickiewicza 24-28, 30-059 Krakow and †Department of Clinical Sciences, School of Veterinary Medicine, University of Agriculture, ul. Nowoursynowska 159c, 02-776 Warsaw, Poland. Keywords: horse; epididymis; granuloma; adenomyosis; stallion; fertility

Introduction of the epididymides revealed bilateral nodules in the epididymal bodies. The nodules were located parallel to each Epididymal abnormalities in stallions appear to be rare. other; their consistency was firm, with the left nodule being Pathologies identified include epididymitis, granuloma and slightly larger than the right. In addition, the stallion neoplasia (Blue and McEntee 1985; Held et al. 1989, 1990, exhibited slight signs of pain during palpation of the 1992; Traub-Dargatz et al. 1991; Brinsko et al. 1992). These epididymal nodules. lesions may have a detrimental effect on a stallion’s fertility and treatment is often unsuccessful. Orchidectomy is usually Evaluation of semen performed in order to relieve the symptoms. This report describes a case of a bilateral epididymal adenomyosis Two samples of semen were collected using a Missouri model in a stallion, associated with infertility. artificial vagina and a breeding phantom with a live oestrous mare standing next to the phantom. The stallion showed signs Case details of pain (sudden dismount preceded by a head toss) during each of 4 attempts to collect semen which occurred History consistently after the last pelvic thrust. During the fifth attempt to collect semen, the stallion ejaculated in A 14-year-old stallion (Silesian breed) was rejected from a conjunction with the application of hot compresses on the breeding programme because of fertility problems. The base of the penis. The second collection of semen was stallion had been used for natural breeding of 4–45 mares uneventful and the stallion ejaculated on the first mount per season for 9 consecutive years (1992–2000) at various without additional stimulation. breeding stations in northern Poland. During the 2001 breeding season, none of the 10 mares bred to this stallion over multiple ovarian cycles became pregnant. The stallion was withdrawn from the breeding station and returned to the stallion depot for a detailed evaluation. The attending veterinarian evaluated multiple semen samples collected from this stallion and reported necrospermia with a consistently high number of tailless heads of spermatozoa in all ejaculates.

Clinical findings

A complete breeding soundness evaluation was performed. Initial palpation of the scrotal contents revealed the presence of 2 scrotal testes of normal size and consistency. Palpation

*Author to whom correspondence should be addressed. Present address: Department of Large Animal Clinical Sciences, College of Fig 1: Ultrasonographic image of the left testis with the Veterinary Medicine, University of Florida, PO Box 32610-0136, epididymis; sagittal section. a = Hypoechoic region of the testis; Gainesville, Florida 32610-0136, USA. b = epididymal nodule. 86 EQUINE VETERINARY EDUCATION / AE / APRIL 2006

Fig 2: Colour Doppler ultrasonographic image of the left testis Fig 3: Outpocketing of the epididymal duct. H&E; with the epididymis; sagittal section. a = Area with normal magnification x200. vascularisation; b = area with increased vascularisation; c = area of the epididymis with increased vascularisation.

The quality of semen was very poor in both ejaculates. Total number of sperm was lower than expected in the first ejaculate and significantly decreased in the second (8.2 x 109 and 1.65 x 109, respectively). Only a few spermatozoa were motile in the first ejaculate and 10–20% in the second. There was a very high number of tailless heads in both ejaculates (60 and 73%, respectively) and an increased number of spermatozoa with proximal droplets (26 and 15%, respectively). No reproductively significant pathogens were recovered from the semen sample from the first ejaculate.

Ultrasound evaluation

Transrectal ultrasound evaluation of the internal genitalia was unremarkable. Ultrasound evaluation of the scrotal contents Fig 4: Proliferating small duct. H&E; magnification x200. revealed normal echogenicity of testicular parenchyma except for one hypoechoic area in the left testis (Fig 1). This region epididymides (head, body and tail) and testes (anterior, middle was localised directly under the epididymal nodule in the left and posterior parts and the region located directly under the epididymis. Both epididymal nodules were hypoechoic and nodule). All samples were fixed in Bouin’s solution and stained surrounded by an echoic capsule (Fig 1). The remaining areas with haematoxylin and eosin. Histopathological evaluation of of the epididymides appeared normal on ultrasound the samples taken from the epididymal nodules showed evaluation. Colour Doppler ultrasound evaluation revealed an enlargement of the lumen of the epididymal duct, multiple increased number and diameter of small vessels in the outgrowths of the epididymal duct into interstitium and hypoechoic region of the testicular parenchyma in the left muscular layer, focal denudation of the epithelium, necrotic testis. Epididymal nodules had areas of increased vascularity, foci scattered throughout the interstitium, proliferation of small mostly on the periphery (Fig 2). A tentative diagnosis of bilateral chronic epididymo-orchitis was made. ducts with columnar, nonciliated cells within interstitium and a thickened muscular capsule (Figs 3 and 4). Numerous cross- Clinical pathology sections of the epididymal duct on the right side were collapsed and extravasation of sperm cells forming a large sperm On completion of clinical evaluation, the stallion was castrated granuloma was found in the adjacent tissue (Fig 5). Small and the testes and epididymides examined. Epididymal nodules necrotic granulomas were also found within the left and right were easily identified in the middle portions of the epididymal epididymal nodules. Multiple large and small blood vessels and bodies. There were small distinct areas of brown discolouration lymphatic vessels were also seen in connective tissue and on the corresponding surfaces of the left testis and epididymis. muscular layer. There was a significant increase in connective Representative samples were taken from all parts of the tissue in the interstitium and a marked thickening of the EQUINE VETERINARY EDUCATION / AE / APRIL 2006 87

characteristics of adenomyosis (Deschamps et al. 1987). Adenomyosis has also been diagnosed in dogs with Sertoli cell tumors that produce excessive amounts of oestrogen (Ladds 1992). Interestingly, oestradiol-treated prepubertal dogs developed severe epididymal changes, including enlargement of the entire epididymis, oupocketings of the epididymal duct or formation of diverticuli and changes in location of capillaries surrounding the tubule (Connell and Donjacour 1985). We did not perform an endocrine profile of the stallion described in this report and therefore cannot address the issue of a possible effect of oestrogens as a cause of this condition. However, the possibility of an effect of phyto-oestrogens cannot be excluded, although it has been shown there is no significant effect of phyto-oestrogens on male fertility in ruminants (Adams 1995). Formation of granulomatous epididymal lesions of ischaemic origin has also been described previously (Nistal et al. 1997). This Fig 5: Sperm granuloma. H&E; magnification x400. pathology occurs in man and causes epididymal occlusion. The lesion is localised in the head of the epididymis and involves efferent ducts as well as interstitial connective tissue. The smooth muscle layer surrounding this region of the epididymis. efferent ducts are distended with signs of necrosis and there is Some epithelial cells of the efferent ducts contained lipofuscin also evidence of intratubular epithelial regeneration and pigment. There were areas of focal testicular degeneration in proliferation of small ducts which have low columnar cells the testes, as well as focal slight infiltration with lymphocytes, without cilia and are devoid of muscular layer. This regeneration interstitial fibrosis, enlarged blood and lymphatic vessels, and process may be an attempt to recanalise sperm excretory ducts Leydig cells containing lipofuscin. These changes were present from the obstruction. We found a similar pattern in samples predominantly in the left testis in the area localised directly taken from the epididymidal nodules of the stallion in our report. under the epididymal nodule. The head of the epididymis in man and rams is supplied by one arterial blood vessel which has no anastomotic connection Diagnosis with other blood vessels. The body and tail of the epididymis receive arterial blood from more than one source (Markey et al. Histopathological findings were consistent with epididymal 1995; Nistal et al. 1997). This anatomical predisposition makes adenomyosis. the head of epididymis especially prone to ischaemic insults. Experimental ligation of the superior epididymal artery in rams Discussion caused all the signs of luminal obstruction of the epididymal duct (Markey et al. 1995). In addition, an accumulation of lipofuscin There have been few reports of epididymal pathologies in pigment was found within epithelial cells. We observed stallions (Blue and McEntee 1985; Held et al. 1989, 1990, lipofuscin within the epithelial cells of the efferent ducts of the 1992; Traub-Dargatz et al. 1991; Brinsko et al. 1992). Lesions affected stallion. Epididymal nodules were localised bilaterally in are usually diagnosed at an advanced stage and are associated the bodies of the epididymides, which is in contrast to the with various clinical symptoms such as pain, scrotal oedema localisation of epididymal granulomas described previously in and gross enlargement of the epididymis. They are usually stallions, rams and man. Interestingly, the head and tail of the caused by chronic epididymitis, and only occasionally by sperm epididymis in stallions are supplied with arterial blood from more granulomas or neoplastic changes. than one source because there are anastomoses between arteria Epididymal granulomas have previously been identified in epididymidis cranialis and arteria testicularis and between arteria stallion epididymides with lesions attributed to migration of caudae epididymidis and arteria ductus deferentis (Collin 1973; parasitic larvae which disrupt integrity of the epididymal duct Jantos˘ovic˘ová and Jantos˘ovic 1983). The body of the epididymis wall. One case of epididymal adenomyosis in a stallion has in the stallion is the only region with a blood supply originating been reported previously (Blue and McEntee 1985). This from a single source (arteria corporis epididymidis). Therefore, condition has also been defined as an invasion of muscular the possibility of an ischaemic insult to this area seems likely. layers and surrounding stroma by epithelium of the epididymal Epididymal sperm granulomas in stallions are usually duct with multiple outgrowths of the eididymidal duct, which associated with poor semen quality. The stallion described in may cause sequestration of sperm and consecutive formation this report had consistently high numbers of tailless heads of of sperm granuloma (Ladds 1992). These features were also spermatozoa in all ejaculates. Similar sperm morphology was noted in the stallion described in the present report. observed in semen collected from a stallion with a sperm It has been suggested that adenomyosis is associated with granuloma described by Held et al. (1989). It has been chronic oestrogenic stimulation. The oestrogen-like agent suggested that an increased number of tailless heads in the zeranol, implanted in bulls, has artificially induced all typical ejaculate is an indication of occlusion of the ampullae (Love et 88 EQUINE VETERINARY EDUCATION / AE / APRIL 2006

al. 1992). Our findings and those of Held et al. (1989) suggest Brinsko, S.P., Varner, D.D., Blanchard, T.L., Relford, R.L. and Johnson, that an epididymal granuloma should also be considered as a L. (1992) Bilateral infectious epididymitis in a stallion. Equine vet. possible cause of an increased portion of tailless heads of J. 24, 325-328. spermatazoa in stallion semen. Collin, B. (1973) La vascularisation artérielle du testicule chez le cheval. Anat. Histol. Embryol. 2, 46-53. Increased vascularisation of one region of the testis and focal areas of the epididymal nodules, found during colour Connell, C.J. and Donjacour, A. (1985) A morphological study of the epididymides of control and estradiol-treated prepubertal dogs. Doppler evaluation of the stallion’s scrotum in our case, Biol. Reprod. 33, 952-969. suggests an inflammatory process. However, our tentative Deschamps, J.C., Ott, R.S., McEntee, K., Heath, E.H., Heinrichs, R.R., diagnosis of chronic epididymo-orchitis was not confirmed. Shanks, R.D. and Hixon, J.E. (1987) Effects of zeranol on Histopathology showed that there was indeed an increased reproduction in beef bulls: scrotal circumference, serving ability, number and size of blood and lymphatic vessels in these semen characteristics, and pathologic changes of the reproductive regions, but only a few foci of lymphocytic infiltration were organs. Am. J. vet. Res. 48, 137-147. found in both testes. Held, J.P., McCracken, M.D., Toal, R. and Latimer, F. (1992) Epididymal All the morphological and histopathological characteristics swelling attributable to generalized lymphosarcoma in a stallion. J. Am. vet. med. Ass. 201, 1913-1915. of the epididymal nodules described in this report strongly supported a diagnosis of epididymal adenomyosis. However, Held, J.P., Prater, P., Toal, R.L., Blackford, J.T. and McCracken, M. (1989) Sperm granuloma in a stallion. J. Am. vet. med. Ass. 194, we could not find a definitive cause of this condition. Chronic 167-268. oestrogen stimulation (phyto-oestrogens) or an ischaemic Held, J.P., Adair, S., McGavin, M.D., Adams, W.H., Toal, R. and insult should be considered, and the involvement of other Henton, J. (1990) Bacterial epididymitis in two stallions. J. Am. vet. factors is also possible. med. Ass. 197, 602-604. Accurate diagnosis of epididymal pathologies is difficult. Jantos˘ovic˘ová, J. and Jantos˘ovic˘, J. (1983) Topographish-anatomische Greyscale and colour Doppler ultrasonography may be helpful Angaben uber die A. testicularis, A. ductus deferentis and in differentiating between epididymitis and benign epididymal A. cremasterica beim Hengst. Gegenbaurs. Morph. Jahrb. 129, masses, but final diagnosis often requires histopathological 467-482. evaluation (Singh et al. 2002; Yang et al. 2003). Ladds, P.W. (1992) The male genital system. In: Pathology of Domestic The bilateral epididymal adenomyosis with sperm Animals, 4th edn., Eds: K.V.F. Jubb, P.C. Kennedy and N. Palmer, Academic Press, San Diego. pp 471-529. granulomas in the stallion described in this report did not Love, C.C., Riera, F.L., Oristaglio, R.M. and Kenney, R.M. (1992) Sperm cause any pronounced clinical symptoms but was associated occluded (plugged) ampullae in the stallion. In: Proceedings of the with severely reduced semen quality and fertility in this Annual Meeting of the Society for Theriogenology, San Antonio, stallion. Further improvement of diagnostic methods is Texas. pp 117-125. necessary to increase our ability to recognise causes of Markey, C.M., Jequier, A.M. and Meyer, G.T. (1995) Effects of epididymal lesions in stallions. ischaemia on the caput epididymis and its relationship to higher epididymal obstruction. Int. J. Andro. 18, 185-196. Acknowledgements Nistal, M., Mate, A. and Paniagua, R. (1997) Granulomatous epididymal lesion of possible ischemic origin. Am. J. Surg. Pathol. , 951-956. This study was supported by the Polish Committee for 21 Research Grants (5PO6D01117). The authors would like to Singh, I., Dev, G. and Singh, N. (2002) Chronic epididymitis (epididymal nodule) mimicking an adenomatoid tumor-case report thank Maciej Florysiak and Sebastian Harnik for help with with review of literature. Int. Urol. Nephrol. 34, 219-222. this study. Traub-Dargatz, J.L., Trotter, G.W., Kaser-Hotz, B., Bennett, D.G., Kiper M.L., Veeramachaneni, D.N.R. and Squires, E. (1991) References Ultrasonographic detection of chronic epididymitis in a stallion. J. Am. vet. med. Ass. 198, 1417-1420. Adams, N.R. (1995) Detection of the effects of phytoestrogens on sheep Yang, D.M., Kang, J.H. and Kim, H.S. (2003) Differential diagnosis and cattle. J. anim. Sci. 73, 1509-1515. of focal epididymal lesions with gray scale sonographic, color Blue, M.G. and McEntee, K. (1985) Epididymal granuloma in a Doppler sonographic, and clinical features. J. Ultrasound Med. 22, stallion. Equine vet. J. 17, 248-251. 135-142. 88 EQUINE VETERINARY EDUCATION / AE / APRIL 2006

al. 1992). Our findings and those of Held et al. (1989) suggest Brinsko, S.P., Varner, D.D., Blanchard, T.L., Relford, R.L. and Johnson, that an epididymal granuloma should also be considered as a L. (1992) Bilateral infectious epididymitis in a stallion. Equine vet. possible cause of an increased portion of tailless heads of J. 24, 325-328. spermatazoa in stallion semen. Collin, B. (1973) La vascularisation artérielle du testicule chez le cheval. Anat. Histol. Embryol. 2, 46-53. Increased vascularisation of one region of the testis and focal areas of the epididymal nodules, found during colour Connell, C.J. and Donjacour, A. (1985) A morphological study of the epididymides of control and estradiol-treated prepubertal dogs. Doppler evaluation of the stallion’s scrotum in our case, Biol. Reprod. 33, 952-969. suggests an inflammatory process. However, our tentative Deschamps, J.C., Ott, R.S., McEntee, K., Heath, E.H., Heinrichs, R.R., diagnosis of chronic epididymo-orchitis was not confirmed. Shanks, R.D. and Hixon, J.E. (1987) Effects of zeranol on Histopathology showed that there was indeed an increased reproduction in beef bulls: scrotal circumference, serving ability, number and size of blood and lymphatic vessels in these semen characteristics, and pathologic changes of the reproductive regions, but only a few foci of lymphocytic infiltration were organs. Am. J. vet. Res. 48, 137-147. found in both testes. Held, J.P., McCracken, M.D., Toal, R. and Latimer, F. (1992) Epididymal All the morphological and histopathological characteristics swelling attributable to generalized lymphosarcoma in a stallion. J. Am. vet. med. Ass. 201, 1913-1915. of the epididymal nodules described in this report strongly supported a diagnosis of epididymal adenomyosis. However, Held, J.P., Prater, P., Toal, R.L., Blackford, J.T. and McCracken, M. (1989) Sperm granuloma in a stallion. J. Am. vet. med. Ass. 194, we could not find a definitive cause of this condition. Chronic 167-268. oestrogen stimulation (phyto-oestrogens) or an ischaemic Held, J.P., Adair, S., McGavin, M.D., Adams, W.H., Toal, R. and insult should be considered, and the involvement of other Henton, J. (1990) Bacterial epididymitis in two stallions. J. Am. vet. factors is also possible. med. Ass. 197, 602-604. Accurate diagnosis of epididymal pathologies is difficult. Jantos˘ovic˘ová, J. and Jantos˘ovic˘, J. (1983) Topographish-anatomische Greyscale and colour Doppler ultrasonography may be helpful Angaben uber die A. testicularis, A. ductus deferentis and in differentiating between epididymitis and benign epididymal A. cremasterica beim Hengst. Gegenbaurs. Morph. Jahrb. 129, masses, but final diagnosis often requires histopathological 467-482. evaluation (Singh et al. 2002; Yang et al. 2003). Ladds, P.W. (1992) The male genital system. In: Pathology of Domestic The bilateral epididymal adenomyosis with sperm Animals, 4th edn., Eds: K.V.F. Jubb, P.C. Kennedy and N. Palmer, Academic Press, San Diego. pp 471-529. granulomas in the stallion described in this report did not Love, C.C., Riera, F.L., Oristaglio, R.M. and Kenney, R.M. (1992) Sperm cause any pronounced clinical symptoms but was associated occluded (plugged) ampullae in the stallion. In: Proceedings of the with severely reduced semen quality and fertility in this Annual Meeting of the Society for Theriogenology, San Antonio, stallion. Further improvement of diagnostic methods is Texas. pp 117-125. necessary to increase our ability to recognise causes of Markey, C.M., Jequier, A.M. and Meyer, G.T. (1995) Effects of epididymal lesions in stallions. ischaemia on the caput epididymis and its relationship to higher epididymal obstruction. Int. J. Andro. 18, 185-196. Acknowledgements Nistal, M., Mate, A. and Paniagua, R. (1997) Granulomatous epididymal lesion of possible ischemic origin. Am. J. Surg. Pathol. 21, 951-956. This study was supported by the Polish Committee for Research Grants (5PO6D01117). The authors would like to Singh, I., Dev, G. and Singh, N. (2002) Chronic epididymitis (epididymal nodule) mimicking an adenomatoid tumor-case report thank Maciej Florysiak and Sebastian Harnik for help with with review of literature. Int. Urol. Nephrol. 34, 219-222. this study. Traub-Dargatz, J.L., Trotter, G.W., Kaser-Hotz, B., Bennett, D.G., Kiper M.L., Veeramachaneni, D.N.R. and Squires, E. (1991) References Ultrasonographic detection of chronic epididymitis in a stallion. J. Am. vet. med. Ass. 198, 1417-1420. Adams, N.R. (1995) Detection of the effects of phytoestrogens on sheep Yang, D.M., Kang, J.H. and Kim, H.S. (2003) Differential diagnosis and cattle. J. anim. Sci. 73, 1509-1515. of focal epididymal lesions with gray scale sonographic, color Blue, M.G. and McEntee, K. (1985) Epididymal granuloma in a Doppler sonographic, and clinical features. J. Ultrasound Med. 22, stallion. Equine vet. J. 17, 248-251. 135-142.