Two things that come to mind for the kidneys: the chinese herbal combination Rehmannia six, and a puree of raw beef kidneys and water. Puree fresh raw kidneys with an equal amount of water, and give him at least an ounce twice a day. Do not heat or microwave this. He would also do well with fish oil and Coenzyme Q10. And make sure he has plenty of fresh water, along with adding salt to his food to encourage him to drink. Good luck.