PANCREATITISes IN CATS
Pancreatitis, or inflammation of the pancreas, is a disease seen frequently in dogs. In cats it used to be considered rare but we now believe that it is simply difficult to diagnose when it occurs and is probably a common problem, especially in older cats. The pancreas is an important organ located near the small intestine. It is responsible for the production of most of the enzymes that digest food, and it also produces insulin. When the pancreas is diseased or injured, the enzymes it produces leak in and around the pancreas, damaging it and the other organs nearby. These enzymes that are leaking out break down fat and protein locally, instead of traveling down the pancreatic duct to the intestines. In effect, the cat or dog digests its own tissues. The abdomen soon becomes inflamed, and may subsequently become infected.
An animal with pancreatitis may show such symptoms as lethargy, fever, vomiting, diarrhea (which is often bloody), refusal to eat and abdominal pain. Symptoms may start suddenly or come on gradually, and can range from mild and intermittent to severe and life-threatening. In cats it is often subtle, appearing as vague signs such as poor appetite or gradual weight loss, without the more dramatic signs that are usually seen in dogs.
The disease may be seen in any breed at any age, but it seems to be more common in older pets. Pancreatitis in dogs often occurs soon after ingestion of garbage, dead animals or a fatty meal (scraps of fatty meat, cheese, whole milk, chicken skins, etc.). In most cases in cats, however, the disease is caused by the body’s own immune system. For unknown reasons the pancreas becomes inflamed and invaded by two kinds of white blood cells, called plasmacytes and lymphocytes. These cells react and multiply as if the body is being invaded by something, but no abnormal bacteria or viruses are found. This inflammatory reaction gradually worsens with time and may also be found in the liver, stomach or intestines.
There are many factors which contribute to pancreatitis. Among them are obesity, infectious diseases, inflammatory bowel disease (IBD), food allergies and kidney disease. Reflux of intestinal contents into the pancreatic ducts may be a significant factor also. Whatever the cause, once the pancreas is damaged a vicious cycle is established as more enzyme leakage leads to more damage, leads to more leakage, etc.
Pancreatitis can be easily confused with many other diseases and conditions which cause similar symptoms. A physical exam will reveal whether your pet is feverish, dehydrated or painful. Blood tests are usually done to ascertain whether an infection is present, and sometimes we also test for higher than normal levels of pancreatic enzymes in the blood. Unfortunately, in many cats these enzyme levels are normal,
even in the face of severe inflammation. Because the liver is located next to the pancreas, liver inflammation is often evident on blood tests and may need to be treated as well. Abdominal radiographs (x-rays) may assist in the diagnosis, and in assessing the extent of the damage. If the diagnosis is uncertain, an ultrasound of the abdomen may be recommended, although like the blood testing a cat with pancreatitis may have a normal-appearing pancreas on ultrasound. The only sure way to diagnose pancreatitis is with a biopsy. This can be done with an exploratory abdominal surgery or using laparoscopic instruments, which allows smaller incisions and faster recovery.
Treatment depends on the severity of the disease, but in acute cases includes antibiotics, withholding food for one or more days to allow the digestive tract time to heal, drugs to control vomiting and diarrhea, and fluids or shock treatment as necessary. We may also decide to feed a bland, low fat diet for at least the first few days after an episode of pancreatitis. In dogs this is very helpful but in cats it’s not clear whether a low fat diet is beneficial, though it isn’t harmful either. Cats with chronic or recurrent pancreatitis may be treated with digestive enzymes and either bland, low fat diets or hypoallergenic diets, depending on whether IBD or intestinal problems are present as well.
Pancreatitis is a serious and life threatening disease. Even with intensive care, in severe, acute cases the cat may not survive. Chronic or severe pancreatitis may also lead to peritonitis, diabetes and pancreatic insufficiency – an inability of the damaged pancreas to produce enough enzymes to enable food to be digested. This last problem is particularly common in cats, especially with the chronic, low-grade form of the disease. Because pancreatitis is difficult to diagnose in cats we may start adding digestive enzymes to the food when we suspect the disease, to see if the cat eats and feels better. Although corticosteroid drugs such as prednisolone help counteract the over-reactive immune system that can cause the disease, steroids can also make pancreatitis worse. It can be difficult to juggle the pancreatitis along with liver disease and IBD. These three diseases often occur in conjunction and together are known as Triad Disease. Although it can be treated and managed, Triad Disease is usually eventually fatal.
To avoid pancreatitis feed your cat a good quality food, avoid overfeeding and table scraps, and keep your pet away from garbage, dead animals and other sources of digestive upset. In acute cases due to infection or injury to the pancreas, more common in younger cats, treatment will be needed for a week or two. In most cases an exact cause is not obvious and a careful work-up and diagnostic testing will be needed to diagnose the disease. In the chronic form, treatment may be necessary for the rest of the cat’s life.