Question:
My 7 month old rescue kitten presented with swollen lymph nodes and gingivitis late November. He has tested negative for FLV/FIV three times. Amoxicillin took care of it but a week after treatment he became lethargic so I took him in and they found a small lemon size lump in his belly.

After aspiration and xrays they went in and did a biopsy and told me it was 99% most likely cancer. When the biopsy came back guess what, it's turns out the lump is the swollen intestinal lymph node itself. I thought that was good news but I'm $2500 into it now and they can't tell me what's wrong with him. They are thinking FIP even though he doesn't have any of the classic symptoms.

His fever and lethargy are the only symptoms, no other problems. He is eating just fine since prednisone. He is also taking Flagyl, and we discontinued amoxicillin to try clindamycin in case of toxoplasmosis. He has days with no fever then days at 104. I can't seem to get a handle on it. We tried special food. My latest attempt at diagnosing him with something non-fatal is a mycoplasma infection since he tries to eat clay litter whenever it's around.

Does any one have any experiences with these two diseases?

Answer:
I'm sorry he's sick, I don't have any experience with this but I did find an article that lists some of the symptoms that go with FIP, it looks like he may have or may have had some of them e.g the swollen lymph nodes:http://www.animalhealthchannel.com/fip/symptoms.shtml
Diagnosis
A diagnosis of FIP usually is based on the animal’s clinical signs and symptoms, x-rays, routine laboratory tests, and an evaluation of the fluid in the abdominal or chest cavity. Some cases, however, are difficult to diagnose because the symptoms vary greatly and are similar to those of other diseases. In all cases, microscopic examination of a tissue sample (biopsy) is the only way to confirm a diagnosis of FIP.

Tests
FIP is notoriously difficult to diagnose through standard laboratory blood tests, and many veterinarians simply do not bother with them. Those who do, generally use blood tests to look for an elevated level of gamma globulin proteins or a low level of albumin in the blood.
I hope someone with experience will be able to give a more definitive response. If you think it is a parasitic infection maybe there is another vet that could test him if your current one has exhausted his investigation? I guess it also depends if you can keep paying out. In the mean time maybe look into adding some more alternatives for the symptoms like homeopathics:http://www.here/articles/article-homeo.html and continue with a special diet or find another. My fingers are crossed for you and your kitty.

Answer:
Little bit more info about why he may be eating clay kitty litter:http://www.wisegeek.com/why-is-my-ca...tty-litter.htm
This article also goes on to mention that an abscsess could even be a possible reason for a kitty to start eating clay. As for adult cats and kittens that are not just being kittens, eating kitty litter is a common symptom of anemia. Anemia is a medical condition where there is an insufficient number or volume of red blood cells and hemoglobin in the body. The most visible sign of anemia in a cat or kitten other than eating kitty litter is paleness. You can check to see if your cat is pale by lifting her lips and looking at her gums. Normally the cat’s gums will be a healthy pink color. It’s important to note that some cats have very dark pigment in their gums which is normal.
http://www.shirleys-wellness-cafe.com/clay.htm Animals, domestic and wild alike, instinctually drawn to clay deposits have been observed licking the clay as part of their everyday diet, and rolling in it to obtain relief from injuries. Clay has helped cows with scours and pneumonia. Veterinarians use it on dogs, cats, horses, etc... for various afflictions including injuries and infections. Recently more information has become available outlining the important role clay can play in the recovery and maintenance of health. Many wild animals, and some people, develop 'pica' when ill, a craving to eat earth - particularly clay, which assuages diarrhoea and binds to many plant poisons.
I don't know exactly how accurate this information is but it seems to make sense. Also cats sometimes eat charcoal for similar reasons and when on "toxic" medications. Be sure he doesn't get into any clumping litter.

Answer:
If you are still there, a medication called interferon to treat FIP is mentioned in this thread:
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