Presentation
Workup for right-side hydronephrosis reported in the recent ultrasound evaluation.
Patient Data




No obvious stone is noted in the urinary tract lodge in the non-contrast image.
After contrast media administration, both kidneys are visualised on the nephrogram image with normal shapes and smooth borders. The right kidney is relatively enlarged. On pyelogram images, the urinary collecting system of the right kidney and the right ureter are duplicated. Moderate to severe hydroureter is present in the upper moiety of the right kidney, with a large distal ureterocele showing a typical cobra head appearance and is bulged into the urinary bladder. In addition, mild hydronephrosis is observed in the lower moiety of the right kidney.
The left renal collecting system and the left ureter appear normal.
Case Discussion
This case typically demonstrates a right-sided duplex kidney with double ureter, also known as a bifid collecting system, accompanied by obstruction of the upper pole moiety down to the bladder, with a ureterocele.
Duplex kidney anomalies can be classified depending on the level or lack of fusion. A duplex kidney with two separate pelvicalyceal collecting systems uniting at the PUJ or as bifid ureters is known as a bifid collecting system. Obstructing the upper pole with a ureterocele and vesicoureteric reflux into the lower pole moiety, often due to distortion in its insertion by the ureterocele mentioned above, are common associations. In addition, ectopic insertion of the upper pole moiety, e.g. into the prostatic urethra in males or a vaginal vault in females, may be seen.