One of my kitties, Raven has liver disease and almost died but I didn't want to give up. She spent many nights in intensive care getting iv's and whatnot. Luckily my vets at the time were in love with her and pushed very hard for her to get better. She had a very small chance of making it. Yet she did. She was put on Science Diet L/D and Denosyl for her medicine. She gets bloodwork ups done every 6 months and since we moved we have switched them to Sensitive Stomach for another cat with problems and she is doing fine on it. As long as Raven gets her daily pill of denosyl she does fine. She was told she had 3 years to live. It's been 4 now
We mostly just try to keep her stress levels down and it helps a great deal. We have spent thousands on her and it is well worth it for me. She's one of my kids.
The vet that helped us through all of this calls her their miracle kitty. ^_^