Answer

Hello!

True autoimmune diseases can be fatal depending on their severity and how well they respond to treatment. There is a wide range that goes from mild that responds to medication for years to severe that doesn't respond well at all. In some cases, there may be an outside agent that is actually responsible for the signs, not the immune system itself malfunctioning.

When dealing with a young cat, there are a number of different viruses that can cause a recurring fever and red blood cell destruction. If he's never been tested for Feline leukemia, Feline AIDs, and Feline Infectious Peritonitis, you may want to look into having that done.

There is another infectious agent called Hemobartonella that can also cause these signs and be tested for. It usually responds well to the antibiotic Doxycycline, which may or may not have been used on your cat yet.

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