Welcome to the board, Ericmpls. I don't know a lot about kidney disease, but I know a little about hip dysplasia and some of the meds frequently prescribed. Which meds is he on for the HD? If he was/is on NSAIDs did your vet say anything about stopping them? Some of them can be pretty hard on a dog's kidneys...
Sending along good wishes for you and your dog!
"We are--each of us--dying; it's how we live in the meantime that makes the difference."
"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
"Be kinder than necessary, for everyone you meet is fighting some kind of battle."