Please help. Young cat with fever of unknown origin question (s)

Hi. We have two 1 year and about 3 month old male cats. Littermates. They were found at about 6 weeks old by a rescue in our area, we adopted them about 6 months later. They shared their own kennel/cage.

Everything has been great, growing, eating, etc. Monday received 1 year distemper and rabies vaccination. Then Saturday morning we had to take one to emergency vet due to not eating, i just knew something was wrong. He had a 105 fever. Stayed overnight on fluids and antibiotics. Fever went down in a few hours and stayed down. Brought home next day, fever back up that night to 104. Called er, we just treated at home with a cool towel. Went down again and has been normal since. My other cat freaked out when sick cat came home from vet, didnt know him, hissed and hid. Got so stressed he wouldn't eat, just like when we first adopted him. So took them both to vet today, they said looked good, a few ounce weightloss since Monday, but vet said due to not eating much for 3 days and some diarrhea, gave them fluids, and appetite stimulant. One that had fever is still on antibiotics. They are both home playing and eating more, but not as much as normal.

Soooo, diagnosed with fever of unknown origin. All labs and x-rays normal except for increased WBC's and slight dehydration. A/G ratio is 8.4, i think -i calculated on my own. I know FIP is a possibility, ER said they dont think so, but my regular vet said if he gets better, to come back in two months and draw his blood again. So that makes me nervous. He also said this all could be a delayed reaction to vaccinations. The other cat not eating he thinks is due to stress. This vet is very, very thorough, sometimes too much.

Anyone ever have a young cat who had a fever with no cause identified? Who just got better? Its been so long since we've had young animals. Our last cat lived to 18. And just because they dont have their full appetite back yet isn't a reason for me to freak out? They are eating much more than yesterday.

Sorry for my babbling and thanks for reading!

Also, they did not do a urinalysis because his bladder was empty when he arrived and then they started fluids and antibiotics.

It does sound like this could be a vaccine reaction with the first cat. The fact that the fever appears to be responding to antibiotics is good and would lead be to believe that, currently, this is *not* FIP. If the fever persisted with antibiotics, I would think differently.

Find out if the FVRCP vaccine was a modified live virus. If so, this would certainly be a possible cause. I have several cats that have vaccine reactions and some have been delayed.

I too think your other cat is likely having problems due to stress. Give things a few days to get back into a normal routine.

Thanks. The fever did go back up the night we took him home but since then its between 101 and 102.5. ER vet said it may wax and wane for a bit.I will ask about vaccine.

Great info and advice from CatPack!

To answer your question regarding a fever of unspecified origin... I've actually had 2 that it has happened to. One was back in the early 90's and another one in 2007 ( I still have him ).

Sending you and your kitties healing vibes I know how scary this can be. Keep us updated on how they are doing & welcome to The Cat Site

An update for today.

The original fever cat is now meowing, running around and eating everything in sight! My little shy guy is starting to eat more also. My vet called me to check on them. My shy guy had some diarrhea, which the vet said could also be from the stress, but now he's thinking they both had some sort of bug that ran through the household. I'm not sure how they would have got one, they never go out? If the second cat still has diarrhea after a couple days, we are to start him on an antibiotic (ugh). I haven't checked either for a fever today, but it's been normal for two days in a row, they are acting fine, so I think no fever.

I asked again about FIP - vet says he doesn't think so, but it's always a possibility. He said he saw some lab values that "may have been slightly suspicious for being possibly values in possibly diagnosing possible FIP" - which is pretty vague! He is just very cautious. So he said 3 months down the line we can come in and do another blood test to see if everything is back to normal. I'm not sure what values he means, as everything was in normal range except for some white blood cells and lymphocytes - which ED vet said was due to him fighting something and some dehydration. So, while I'm a bit calmer, it's still in the back of my mind.

So not completely back to normal yet but soooo much better than the weekend!

Thanks everyone!

Unfortunately there is no clear cut diagnosis for FIP other than the fluid in the stomach/chest that can be tested to see what it is.

It does sound like it could be reaction to the vaccines. Sometimes we carry things in when we go out and about. Some viruses we get for colds are like this. I think the fact that the fever is going away is encouraging. And getting them to eat and drink is very good. I would be puzzled as well.

So glad to hear they are improving. Sometimes stress does strange things to our babies. I have one who pees when we go to the vet-she gets so scared that she soaks the carrier when we are in the vets office. Sometimes they have higher sugar values on blood work due to stress.

You can always call the vet back and ask what exactly they were talking about or ask them to send you an email explaining about these "values" then you can reread it and digest it better?

Keep up the good work! You did good getting them medical care!

That's a great update! Yay kitties!

IMO, if they were exposed to a virus, it was probably at the Vet's office.

You do sound like you have a through vet and a good working relationship with them. Enjoy your kitties and try not to worry about the 3 month check up.
and vibes for continued health and happiness

Hi.

So it's been a little over a week since this all started Saturday before last.

Fever cat has had no fever since day two of this ordeal. Eating, playing, no weight loss - still on antibiotics, (covenia - so far okay). Stressed cat is now  playing and eating normal again also, but still dealing with diarrhea, but getting better - never had fever. Both cats have been started on a probiotic since Friday. If you looked at them today, you would have no idea they were so sick a week ago.

Is there a time to relax and think we are out of the woods with FIP?

thanks.

I think the fact that both are improving and have remained fever-free is excellent and I believe you can relax a bit from worrying this is FIP.

One thing you can do to ease your fevers is to have both tested specifically for Coronavirus. Now, a positive test doesn't mean they will develop FIP and a negative test doesn't 100% mean that they won't. HOWEVER, if the test is negative, there is an extremely small chance that FIP will ever be a concern.

There is also the option to do a titer testing. My vet recommends the 7b ELISA test. But, this is something to discuss with your vet.

Honestly, as long as there is continued improvement, I wouldn't worry.