Although articles and communiqués to cat advocates and health professionals crop up from time-to-time proclaiming successful treatments for Feline Infectious Peritonitis (FIP), including an email this writer received with the byline, Veterinarian Successfully Treats Deadly Feline Infectious Peritonitis (FIP) Disease, the FIP virus remains incurable and a sure death sentence.
In order to dispel numerous claims as to diagnosing and “curing” FIP, the virus itself must first be explained. The feline enteric coronavirus (FECV), which has a crown-shape when viewed under with an electron microscope, is generally benign in and of itself, remaining in a cat’s intestinal tract, with diarrhea as the only obvious symptom, if any at all. Cats are exposed to FECV when the virus is shed in the feces of one cat and orally ingested by another. The virus replicates itself and infected cats shed the virus via their feces for a few months before developing antibodies to the virus. Some cats stop shedding the virus, while others may shed again due to re-exposure to the virus. Some may shed nonstop. Because Coronaviruses are prone to genetic change, what, 99% of the time, is a harmless virus contained in the intestinal tract can exit the intestinal tract and cause problems in a number of organ systems. This is how it’s thought FECV mutates into the deadly FIP.
An immune response is triggered once a cat has FIP, but ironically, the response makes things worse. Antibodies produced to fight FIP have no effect – they bind to the virus, circulate through a cat’s bloodstream and settle down and accumulate in blood vessel walls where they trigger an intense and destructive reaction. Inflammatory lesions form, causing observable symptoms of FIP, such as a persistent, low-grade fever and/or swelling of the abdomen. An immune system cell called a macrophage ingests the virus with the antibody bound to it, but doesn’t destroy it. Instead, macrophages serve as vehicles to spread FIP throughout a cat’s body with most cases occurring right after the first infection. While FIP is rare, the peak FIP infection ages are six months to two years of age. Older cats, although a rarity, can also develop FIP.
FIP can take on two forms, wet or dry. Wet FIP occurs when macrophages circulating around a cat’s body land on blood vessels, causing them to become inflamed and fluid from the blood stream to leak out. This is called a Humoral immune response; Humoral meaning body fluids. Fluid accumulates in a cat’s abdomen, resulting in a distended abdomen; the most common symptom of wet FIP. Fluid may also accumulate in the chest, resulting in breathing difficulty, and/or the membrane surrounding the heart, causing heart problems. Other symptoms can be eye inflammation, central nervous system issues, such as difficulty walking, and/or jaundice when the liver becomes involved. Wet FIP, while easier to diagnose, can be mistaken for cancer and liver diseases. It can also be mistaken for heart disease or Chylothorax (accumulation of lymphatic fluid in the chest cavity) when the chest cavity is filled with fluid.
Dry FIP happens as a result of a response at the cellular level. Granulomas (clusters of accumulated inflammatory cells) build up in different organs, such as the liver and kidneys, causing inflammation. This form of FIP is often difficult to diagnose and can be mistaken for other infections or diseases such as Multiple myeloma, a cancer of the plasma cells. The most common symptom of dry FIP is a persistent low-grade fever that doesn’t respond to antibiotics, weight loss, and increased globulins (proteins found in blood plasma). Symptoms differ depending upon the affected organ(s). Eye inflammation and central nervous system issues are common.
There is no vaccination to prevent FIP and no definitive ways to diagnose either form. The Coronavirus test only tests for the existence of Coronavirus in a cat’s body; not either form of FIP. Dr. Arnold Plotnick, MS, DVM, ACVIM, states it’s important to, “gather up as much evidence as you can” in cases of suspected FIP. Is there a persistent, low-grade fever that doesn’t respond to antibiotics? Is there a high globulin level? This is significant, as the globulin portion of the bloodstream is where all of those FIP antibodies are found. In the case of wet FIP, contrary to claims made by some, the FIP 7b ELISA test, “can’t distinguish between the deadly FIP infection and a harmless Coronavirus infection.” In the case of wet FIP, which is most common in young cats and accounts for two-thirds of the cases of FIP, a piece of evidence often used to make a diagnosis may be obtained by analyzing chest or abdominal fluids. Diagnostic evidence for dry FIP may be obtained by a biopsy of organs via exploratory surgery or a percutaneous needle biopsy (where tissue is obtained using a biopsy needle), in order to examine the tissue under a microscope.
Some have claimed that electrophoresis, a method by which serum proteins are analyzed, can result in a diagnosis of FIP. Again, Dr. Plotnick states this is simply not true, because that test, “only evaluates the type of immune response. The result will only indicate the immune system has been stimulated, but not by what. Electrophoresis can help rule out cancer, but can’t diagnose FIP.”
Some have claimed Lymphocyte T-Cell Immunomodulator (LTCI) therapy can cure FIP. But, Plotnick states LTCI is, “neither a cure nor a treatment for FIP. No peer reviewed studies in reputable journals have shown it to be effective in treating FIP.” He goes on to say, “FIP isn’t curable and is inevitably fatal. There’s a potential treatment for dry FIP on the horizon called Polyprenyl immunostimulant. Several cats with dry FIP have been studied [by Dr. Alfred M. Legendre, DVM] where Polyprenyl immunostimulant was used as a treatment. The drug shows promise in treating cats with dry FIP.”
Dr. Arnold Plotnick, MS, DVM, ACVIM, is the founder of Manhattan Cat Specialists, a cats-only veterinary practice located on the Upper West Side of Manhattan. Plotnick’s practice offers, “routine veterinary services such as vaccinations, dentistry, neutering and spaying… [and] state-of-the-art procedures, including ultrasound, endoscopy, blood typing, microchipping and blood pressure measurement. Plotnick has also designed unique wellness programs for middle-aged cats and geriatric cats.” Dr. Plotnick writes the Ask The Vet column for Cat Fancy Magazine, is one of the feline experts on Catchannel.com, and is the feline health adviser for Petocracy.com.