Hey Gravy. It is very dangerous when cats refuse to eat. They can go downhill fast. How is her water intake? I have had two cats with kidney disease. Lack of food/water intake and weight loss are big signs. I actually saved my mother's cat's life by feeding her 1/2 a can of Fancy Feast every day. She started eating and drinking again and I was able to stop giving her sub cutaneous fluids. I would stop worrying about the gluten for now. Good Luck to you and Octavia.