I don't know why it would jump other than with aging the kidneys are not working as well. Nikki who had a 30 BUN last year is now at a 36 BUN and the vet out him on KD canned as he has no teeth. Nikki is estimated to be 17. His creatinine was up a little too. I know my vet said they can show no symptoms until they have 25% kidney function left so the tests help judge the severity of the disease. I will keep positive thoughts for him. |