Urinary tract infection.
Duplication is the most common abnormality of the ureteropelvic collecting system.
It is a congenital abnormality which covers a spectrum ranging from a simple bifid renal pelvis to a complete ureteropelvic duplication. When complete, duplicated ureters insert separately into the bladder, following the Weigert-Meyer rule which states that. Reflux into the lower pole ureter is more common, presumably because the ureteral orifice is more laterally placed and follows a direct rather than oblique intramural course. The upper pole ureter is more commonly obstructed. An IVP nicely demonstrates the duplicated collecting system and ureters.