Zinner syndrome is a triad of mesonephric (Wolffian) duct anomalies comprising unilateral renal agenesis, ipsilateral seminal vesicle cyst, and ejaculatory duct obstruction ¹.

Epidemiology

The condition is very rare, with ~200 reported cases (c. 2009) ⁹.

Clinical presentation

Patients are typically diagnosed during the 3^rd or 4^th decade of life and often present with perineal pain, recurrent prostatitis, hematospermia, painful ejaculation, and infertility ¹.

Pathology

There is an association between congenital malformations of the seminal vesicle and the ipsilateral upper urinary tract because both the ureteral buds and the seminal vesicles originate from the mesonephric (Wolffian) duct ^2,3.

Maldevelopment of the distal part of the mesonephric duct results in atresia of the ejaculatory duct (leading to obstruction and dilatation of the seminal vesicle), while an abnormality in the ureteral bud leads to renal agenesis/dysplasia ¹. 

Radiographic features

Irrespective of imaging modality, the key findings are ¹:

• unilateral renal agenesis

• ipsilateral ejaculatory duct obstruction

• ipsilateral seminal vesicle cyst

Small testis and ipsilateral ureterocele have also been reported ⁷ .

Treatment and prognosis

In asymptomatic patients, treatment is usually conservative, however, symptomatic patients are often treated surgically which can be open surgery, laparoscopic or robotic assisted surgeries ⁵. A temporary treatment option is transrectal ultrasound-guided aspiration of the seminal vesicle cyst to relief of patient symptoms ¹⁰.

History and etymology

Zinner syndrome was first described by A Zinner in 1914 ⁸.

Differential diagnosis

Seminal vesicle cysts should be differentiated from other cysts such as ⁴:

• prostatic utricle cyst

• Mullerian duct cyst

• ejaculatory duct cyst

See also

• renal agenesis

• seminal vesicle cysts