I think cat has FIP but vets don't think so because of normul globulin but TP is 7.4

Cat Question: I am lost on what to do next for my 8 year old cat Sal, he is a neutered indoor cat that appeared to be healthy untill three months ago.It started with bringing a 6 month old kitten from the pound home, which he was tested for fiv and feluk and was neg.two of my other cats came down with lose very smelly bowel movements that ended with bright blood,my other two have never had this problem before, but two months after being treated with azithomicin for two weeks it went away but then he started to vomit clear liquid that increased of a month,I switched him from scince diet m/d to what he was fine on before all this is purina one, but he seems to decline, he still eats normally and drinks with no lose stools, normal color, but he is very lethargic really has no interest with toys or the laser light he goes crazy with, no weight loss but muscle mass to me seems to be depleted, he has had three blood with draws that seem to stay the same, the only ones that raised a slight concern to the vets is a little lower WBCof 6.00 a higher raised monocytes of 50% and mild decrease neuophilis of 2300 which I was told the norm was 2500, his globulin levels were normal with a 4.2 .
The only thing I can think of is FIP, but the vets arent quite sure but dont think so cause of a nomal globulin, however his total protien was 7.4, Im really lost on figuring it out, the Internal medicine vet dosent really know but wants to rule out FIP, but I cant.. It all started when I brougt home a cat from the pound which he appears to be healthy,he has tested neg for feluk and fiv twice so any new news would help.

Hi Melina,

Sorry to hear about your situation.

As you probably know the tests for FeLV and FIV are not always accurate, but they are the best we have right now.

(I had a pet cat that died of FelV after three tests two years ago)

FIP is always hard to diagnose as well.

The problem with these diseases is that they very slowly progress over time, which makes giving an accurate diagnosis hard.

I think your vet is doing a good job by doing serial blood samples though.

Without looking at the bloodwork results I can't offer more advice, but by the way you describe things I think your vet is working at trying to figure things out.

This is a difficult case so hang in there,  you cat could recover possibly, so give it good nursing care.