Zinner syndrome, a rare congenital urogenital tract malformation: the first reported case in Indonesia.

Zinner syndrome (ZS) is a rare urogenital anomaly characterized by cystic seminal vesicles, obstructed ejaculatory duct, and ipsilateral renal agenesis, complicating diagnosis and management due to its rarity and nonspecific symptoms.　ZS incidence is 0.0021%, with symptoms typically appearing in the 2^nd and 3^rd decades of life, including dysuria, urinary frequency, perianal pain, and infertility.　MRI is the gold standard for diagnosis, while surgery is reserved for symptomatic patients.　Mildly symptomatic patients receive conservative management, including antibiotics and regular monitoring.　We report the first case of ZS in Indonesia, involving a 36-year-old male presenting with perineal pain similar to an episode a decade earlier.　MRI revealed right kidney agenesis, ejaculatory duct obstruction, a 4.95 cm cyst on the right seminal vesicle, and a right ectopic ureter.　Semen analysis was unremarkable.　Diagnosis of ZS was confirmed, and the patient opted for conservative management.This case highlights the importance of diagnosing ZS in underrepresented regions, where limited awareness and access to advanced tools delay identification.　The conservative approach reflected the patient's preference to avoid surgical risks while achieving effective symptom relief through tailored, patient-centered care.　Clinicians should consider ZS in cases of unilateral renal agenesis with cystic pelvic masses.