大欺騙家：八旬老婦之雙套腎系統輸尿管囊腫誤診為巨大簡單性腎囊腫之罕見病例報告

鍾慧明、黃信文 ¹

花蓮基督教門諾會醫院泌尿科，¹放射科

 Great Mimicker: Rare Presentation of a Duplex System Ureterocele Misdiagnosed as a Huge Simple Renal Cyst in an 80-Year-Old Female

Hui-Ming Chung, Hsing-Wen Huang¹

Department of Urology,  Department of Radiology¹,

Mennonite Christian Hospital, Hualien, Taiwan;

            To report an unusual case of a symptomatic duplex system ureterocele in an octogenarian, which was misidentified as a huge simple renal cyst for 15 years, and to discuss the diagnostic challenges of congenital anomalies in the geriatric population.

            An 80-year-old female presented with acute pyelonephritis, left flank pain, and a 15-year history of recurrent urinary tract infections (UTIs). For over a decade, multiple ultrasound and CT reports from various providers had identified a stable, 15 cm cystic lesion in the left kidney, labeled as a "huge simple renal cyst." The patient had previously declined recommended surgical unroofing.

Upon recent admission, updated CT urography and cystoscopic evaluation revealed the "cyst" was actually a massively dilated, obstructed upper pole collecting system associated with a complete duplex system and a large intravesical ureterocele. The patient underwent successful endoscopic incision of the ureterocele. At 3-month follow-up, she remained asymptomatic with no recurrence of infection. Imaging confirmed significant decompression of the upper pole and preservation of overall renal function.

            While ureterocele is primarily a pediatric diagnosis, it can remain occult until late adulthood. In this case, the extreme size of the dilated upper pole (15 cm) and its location mimicked a simple cortical cyst, leading to a 15-year diagnostic delay. This case highlights a critical surgical pitfall: had the patient undergone the previously recommended cyst unroofing, the distal obstructive pathology would have remained unaddressed, potentially leading to persistent urinary leakage or worsening sepsis.

            Ureterocele should be included in the differential diagnosis of elderly patients presenting with recurrent UTIs and large cystic renal lesions. Endoscopic incision is a safe, minimally invasive, and definitive treatment in the geriatric population, preventing the morbidity associated with misdirected surgical interventions.