Cat FIP (Feline Infectious Peritonitis)
The following information isn’t intended to replace regular
visits to your veterinarian. If you think your cat may have feline infectious
peritonitis, please see your veterinarian immediately. And remember, please do
not give any medication to your pet without talking to your veterinarian
What Is Feline Infectious Peritonitis
Feline infectious peritonitis (FIP) is a viral disease that occurs worldwide
in wild and domestic cats. It is caused by a type of virus called a
coronavirus, which tends to attack the cells of the intestinal wall. In 1970,
the coronavirus that causes FIP was isolated and characterized. In 1981,
another coronavirus was isolated. Although this virus is nearly identical to
the FIP virus, cats who were infected with it developed only very mild diarrhea
and recovered easily.
What Are the Symptoms of FIP?
FIP manifests in a “wet” form and a “dry” form. Signs of both forms include
fever that doesn’t respond to antibiotics, anorexia, weight loss and lethargy.
In addition, the wet form of FIP is characterized by accumulation of fluid in
the abdominal cavity, the chest cavity, or both. Cats with fluid in the chest
exhibit labored breathing. Cats with fluid in the abdomen show progressive,
nonpainful abdominal distension. In the dry form of FIP, small accumulations of
inflammatory cells, or granulomas, form in various organs, and clinical signs
depend on which organ is affected. If the kidneys are affected, excessive
thirst and urination, vomiting and weight loss are seen; if the liver,
jaundice. The eyes and the neurologic system are frequently affected, as
How Is FIP Diagnosed?
Diagnosing FIP is challenging. Despite the claims made by some
laboratories and test manufacturers, there is currently no test that can
distinguish between the harmless intestinal coronavirus and the deadly FIP
coronavirus. A positive test may support the veterinarian’s suspicions, but by
itself is inconclusive. It means only that a cat has been exposed to and may be
harboring a coronavirus. A negative test usually (but not always) indicates
that the cat is unlikely to have FIP.
If a cat has what appears to be the wet form of the disease,
laboratory analysis of some of the fluid can support a diagnosis of FIP. A 1994
study reported that cats with signs suggestive of FIP, who also had a high
coronavirus antibody level, reduced numbers of lymphocytes and high levels of
globulins in the bloodstream, had an 88.9 percent probability of having FIP.
Diagnosing the dry form of the disease is even more challenging, often
requiring biopsy of affected organs.
How Is FIP Treated?
FIP is fatal in more than 95 percent of cases. In mild cases of
the dry form, it may be possible to prolong the survival period, but most cats
with the wet form of the disease die within two months of the onset of signs.
Fortunately, the disease is very uncommon. In households containing only one or
two cats, the FIP mortality rate is around one in 5,000.