Just a little FYI for people who do not understand renal failure. When the kidneys are scarred and shrinking they cannot filter poisons out of the body any more. This is considered end stage .... here is something for people who do not know this to read:
Canine Kidney Disease : Family Pet Veterinary Center
I have been through this with two pups....they both passed away in 2010. One was 12 and the other was 15. They lived for a long time after their initial diagnosis with good vetting and good care; but there came a time when their quality of life was no longer there. Anyone who knows me knows I would take my pups to another planet and sell every single thing I own if I had to, to keep them alive. Renal failure in the end stages makes them very ill and there does come a time that no matter what you do, it will not save them.