Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
I am sorry Tomkins is experiencing these symptoms, but glad you had him seen by his veterinarian and started with some basic lab work. That does help us rule out some of our more common causes for a high fever. There is a HUGE list of potential issues that could cause what you report which are non-specific symptoms associated with running a high fever. Were you given a reason for him being placed on prednisone? This is a drug we must use with a specific reason in a cat with a high fever and unclear if due to an infectious disease. Just wondering on that. I think the antibiotic/mirtazapine are very appropriate as are the fluids (which should be repeated as needed for as long as he is not eating).
The bad news is the next step, if he is not responding to his current therapy, is to do more testing. If not already done the next step would be some imaging which could be radiographs (X-rays) followed by an abdominal ultrasound. This helps us look for any possible source of infection. If nothing is found then further screening for infectious diseases are warranted such s toxoplasmosis, bartonellosis, fungal diseases and consider screening for FIP. Unfortunately with high proteins FIP (feline infectious peritonitis, the dry form) would be high on my list. The very frustrating part is there is no good screening test (prior to death) for this. We have tests we can do to gain a suspicion this might be the problem, but no definitive testing without biopsies to really get confirmation. Imaging, ultrasound in particular, can often be very helpful in trying to diagnose this problem. I also highly recommend a very good retinal exam. There is also no treatment for FIP. So, we generally hope this is not the cause as the prognosis is grave for survival with this condition. This is why we diligently search for another cause.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
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