Zinner syndrome: an uncommon cause of painful ejaculation.

Zinner syndrome refers to the triad of ipsilateral renal agenesis, seminal vesicle cysts and ejaculatory duct obstruction. Ipsilateral renal agenesis may be associated with seminal vesicle cysts in 70% of cases, but a remnant ureteral bud has been shown to coexist in only 27% of these cases. While some patients may remain asymptomatic and are discovered incidentally, others present with symptoms related to seminal vesicle cysts or ejaculatory duct obstruction: voiding or ejaculatory difficulty or pain. The diagnosis is made with imaging findings, and differentiation from other pelvic cysts requires a multimodality approach. In this report, we present typical imaging findings of a patient who presented with painful ejaculation where there was a congenital seminal vesicle cyst with ipsilateral renal agenesis associated with a remnant ureteral bud draining into the seminal vesicle cyst and also associated with a cyst of the prostatic utricle. We discuss the relevant embryological basis for this unusual combination of findings.