question: Hi I have been diagnoised with UPJ (Congenital probably) Obstruction and also my left kidney is  doing 20 per cent of work, right kidney 80 per cent of work. Urologist said we could either monitor 3, 6, 9 months with renal scans , or have surgery- Pyeloplasty Surgery. My left kidney is not filtering my waste quickly enough or as much as it should be. I had a stent inadverdently left in my kidney for 17 months, and then I had incontenance problems, blood in urine, back pains, stomach pains & fever. I have retained the services of a 2nd urologist for a second opinion. My real question is... is this a diagnosis/surgery for a urologist or for a nephrologist, since my kidney is messed up?!