We had four cats- 5 years ago cat #1 got kidney failure and almost died (she was 5). She miraculously recovered after two years of home water injections. Then cat #2 got kidney failure 3 years ago (she was 7)- despite our best efforts, she died.
Then 2 years ago cat #3 got kidney failure (she was 5). We treated her and at that point I caught on to the fact that there were toxic ingredients in most commercial cat food....the whole rat poison/Chinese gluten thing hit the news.
Ironically, one of the recalled canned foods was a high priced canned vet food for cats with kidney problems.
None of the foods I had been feeding our cats were on the recall list- yet I'm convinced they all had bad things in them.

Since then, for the past two years I feed only Newman's organic pellets and a mix of my own homemade stuff....and our 3 kitties have been thriving ever since.
Kidney failure is not just an old cat issue- there are bad things in lots of commercial pet food, and I bet there still is bad stuff in it.