Duplex kidney anomalies and associated pathology: a single centre retrospective review

Debanga Sarma, Sarbartha Kumar Pratihar, Rajeev T. P., Sasanka K. Barua, Puskal K. Bagchi, Mandeep Phukan


Background: Duplex kidneys are common developmental renal anomaly with an incidence of 1% in healthy adult population.Adult individuals may present as non-functional moiety, calculus disease or an incidental finding. Duplex kidney is defined as a renal unit comprised of two pelvicalyceal systems. Based on the degree of fusion, it can present as bifid renal pelvis, partial ureteric duplication (Y-shaped ureter), incomplete ureteric duplication with ureters joining near or in bladder wall (V-shaped ureter) and complete ureteric duplication with separate ureteric orifices. The purpose of this study is to retrospectively review the various duplex kidney anomalies and associated pathology.

Methods: This is a retrospective study, performed at Department of Urology, Gauhati Medical College Hospital, a tertiary centre, from September, 2018 to August, 2019. Preoperative imaging, plain intravenous urography or computed tomography intravenous urography was done.

Results: 29 patients were diagnosed with variants of duplex kidney anomaly. It includes right side, left side and bilateral anomalies. Among all the patients 4 had incidental findings. 16 patients had associated renal or ureteral calculus. 5 patients had associated ureteropelvic junction obstruction while 1 patient had ureterovesical junction stricture. We found single patient in each group of duplex kidney anomaly associated with non-functional moiety with renal cell carcinoma, ureterocele with urothelial malignancy and horseshoe kidney with ureteropelvic junction obstruction respectively.

Conclusions: Duplex kidney anomaly in most individuals is of no clinical significance. High index of suspicion along with good quality imaging can accurately detect specific anomaly and associated condition.


Duplex kidney anomaly, Bifid pelvis, Complete ureteral duplication

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