really sick cat

Question
I have a 10 year old cat. She seemed healthy and ate well until one week ago. I noticed she seemed to be losing weight but thought nothing of it. On Tuesday, she vomited a few spots of "bile". The next morning she vomited a lot and was hiding away. She did not want to eat. We went to the vet - all blood tests are normal and show nothing. he gave her fluids @ a vitamin shot. She has not improved. She is very weak, will not eat and stays in the closet. I am feeding her with a syringe. We took her in again and she got more fluids and an appetite stimulant. She is getting worse. I think she may have some form of lymphoma. This was so sudden. It cannot be her food, my other cat of the same age is fine. I think I may have no option but to put her to sleep. I do not want her to suffer.

Answer
Hi Cheryl.  I'm so sad to hear your news.  It is always horrible when a cat falls ill, and it's even worse when you have no idea what's going on.

Have you had an x-ray done?  While blood tests have their benefits, I find x-rays are often at least as helpful.  It can show if organs are of an abnormal size, texture, if there is fluid where it shouldn't be or if there is gas where it shouldn't be.  These can suggest cancer, heart failure or serious infection.  I think if this was my own kitty, I'd do an x-ray in hopes of some answers.

I know you said her blood tests all came back normal, and I would assume the vet hasn't placed her on antibiotics because her blood counts were all within a healthy range?  I don't know if giving a broad-spectrum antibiotic a shot as a last ditch effort may be worthwhile.  It would seem to me that at this point, it couldn't really hurt, so it may be something to discuss with the vet?

I'm glad you are keeping her needs first and won't allow her to suffer.  Sometimes we have to make decisions without all the answers we'd like to have, and I would certainly support your decision to put her to sleep if she isn't responding to any treatments.  I'm not sure how you feel about it, but an autopsy can often give you some peace of mind about your decision.