A case report of rare Zinner syndrome: An ejaculatory duct cyst was present Instead of an ipsilateral seminal vesicle cyst

Abstract Background Zinner syndrome (ZS) is a malformed triad of congenital mesonephric (Wolffian) duct dysplasia that was first described by Zinner in 1914. ZS consists of unilateral renal hypoplasia or dysplasia, ipsilateral seminal vesicle cysts, and obstruction of the ejaculatory duct. The present case is a rare type of syndrome in which an ejaculatory duct cyst was observed rather than an ipsilateral seminal vesicle cyst. The ejaculatory duct cyst involved the vas deference bilaterally, resulting in bilateral seminal vesicle gland atrophy or erosion, without apparent seminal fluid, which caused azoospermia and infertility. Case presentation: The patient had only a feeling of incomplete defecation, accompanied with a little anal distension before surgery. No sperm were found on two semen examinations, and magnetic resonance imaging/magnetic resonance urography (MRI/MRU) suggested the absence of a left renal component and the possibility of a seminal vesicle cyst. We considered that the azoospermia was caused by compression of the contralateral ejaculatory duct by a seminal vesicle cyst on the affected side, so we decided on laparoscopic resection. No seminal vesicle cyst was found during the operation, but an ejaculatory duct cyst was detected in which the bilateral vasa deferentia merged with no other outlet. We resected the cyst. After surgery, the patient's clinical symptoms disappeared, but the infertility problem could not be solved. Conclusion Although we had a preliminary confirmation of the ZS diagnosis with azoospermia before surgery, it exhibited a variation that has not been reported in the literature, and such a variation could not be resolved by surgical resection alone. Preoperative deferento-vesiculography(DVG) is necessary to confirm the diagnosis. Assisted reproductive technology could be utilized for the azoospermia caused by the ZS.