My daughter was diagnosed with the very same thing...it was her left kidney she had an upper and lower pole kidney and two ureters draining to her bladder...they found that her kidney was dialated in the womb...after being born she had to have several tests and finally the doctor decided she had to have surgury...doc went in and removed the upper half of her kidney, removed the extra ureter and reinserted the good ureter back into the bladder, she had a stint? put in her ureter to keep scar tissue from deveoping, had that removed I think a week or two later. She is perfectly fine now...just a smaller kidney on her left side, but works normally. I was a wreck at the time she was going through this, I had no idea what a duplicating collecting system was and was very scared for her. She is now two years old and is doing great, she has two scars one on her side and one in the bikini area. I hope everything for you goes as well as my daughter did. Surgury is always scary especially if its one of your children, but this surgury is better than not having it at all. Best of luck!