Pancreatitis is inflammation of the pancreas caused by leakage of active digestive enzymes into the pancreatic tissue. This causes various clinical signs but most pets affected by acute pancreatitis have abdominal pain, depression and decreased appetite or lack of appetite. Vomiting and diarrhea occur in many dogs with pancreatitis. In severe cases of pancreatitis there may be signs of shock or total collapse. Chronic pancreatitis in dogs may occur, with similar but less severe symptoms. The signs of acute pancreatitis similar to those seen in dogs are not as common in cats and probably account for less than 25% of the cases of pancreatitis among felines. Cats are more likely to have chronic pancreatitis, characterized by a decrease in appetite, lethargy, loss of weight, chronic vomiting and low body temperatures. Cats sometimes have diarrhea or difficulty breathing.
The pancreas has several jobs that it performs for the body. The pancreas produces digestive enzymes that break down food into molecules that can be absorbed from the intestine. Special clusters of cells in the pancreas, the islets of Langerhans, produce insulin. Diabetes occurs when these cells do not function properly or when they no longer function at all.
It is unusual for acute pancreatitis to cause acute diabetes mellitus and unusual for chronic pancreatitis to lead to diabetes mellitus, but there are cases in which these things happen. These complications are much more common in dogs than in cats. It is particularly important to be aware of the possibility of diabetes occurring with severe acute pancreatitis and just as important to remember that this is usually a temporary situation. It is critical to monitor insulin needs very closely if an attempt is made to correct high blood sugar using insulin in a dog with acute pancreatitis, in order to avoid the risk of shock due to an over dosage of insulin when the islet cell function returns and the pancreas begins to make insulin normally.
Digestive enzymes produced by the pancreas are capable of digesting the dog or cat's body just as well as they digest food. For this reason there have to be very good self-protective mechanisms in the body to keep the digestive enzymes from leaking and to deactivate them when they are leaked. Both of these mechanisms have to work well in order to prevent pancreatitis. There are a large number of things that can interfere with the protective mechanisms of the pancreas.
Pancreatitis is more common in overweight pets. When pancreatitis occurs in an overweight pet it is more likely to cause serious illness, as well. This is one of the many good reasons to keep your pet at or close to its ideal weight.
High fat diets, especially in combination with low protein intake, appear to contribute to the development of pancreatitis. A single high fat meal may cause pancreatitis in a pet whose normal diet is moderate or low in fat. We see an increase in cases of pancreatitis around Thanksgiving, Christmas and Easter almost every year, presumably due to the ingestion of high fat leftovers from the big meals associated with these holidays.
There are a number of drugs that have been linked to pancreatitis. The most well known of these, prednisone (or other corticosteroids) apparently doesn't actually lead to pancreatitis, at least according to recent information in humans (J.M. Steiner, 2005). The medications most suspected of causing pancreatitis include azathioprine (Imuran Rx), potassium bromide (used for seizure control), l-asparaginase ( a chemotherapeutic agent) and zinc used as a dietary supplement. There are a number of other medications that are sometimes mentioned as possible causes of pancreatitis but the relationship with it is less clear for most of those medications. Pets living in areas in which scorpions occur may develop pancreatitis after scorpion stings. Naturally occurring hypercalcemia ( too much calcium in the blood stream) can lead to pancreatitis and it is likely that over supplementation with calcium or calcitriol could also lead to pancreatitis.
It is unclear whether there is a genetic predisposition to pancreatitis in dogs and cats. Pancreatitis is much more common in miniature Schnauzers than in most other breeds but this could be due to a genetic predisposition to hyperlipidemia (high fat content in the blood stream) rather than a direct genetic link to pancreatitis.
Pancreatitis in cats tends to occur in combination with other disorders, especially inflammatory bowel disease (IBD) and cholangiohepatitis (liver disease). All three of these problems occur at the same time in a fair number of cats and the combination is currently being called "triad syndrome". At the present time it is unclear whether any of these conditions can lead to the other ones or whether they just happen to occur together frequently. It seems likely that IBD may be able to cause chronic pancreatitis but for now this is unproven. All three of these disorders are seen most commonly in older cats and this syndrome is a major cause of chronic weight loss and chronic vomiting in older cats.
Toxoplasmosis, a parasitic infection, can cause pancreatitis in cats. This should be suspected when pancreatitis occurs in young cats, or in groups of cats or when there are other signs of parasite infection such as neurologic disease, visual problems, weight loss or unexplained diarrhea. Another parasitic cause of pancreatitis in cats is a liver fluke, Amphimerus pseudofelineus, which has been diagnosed sporadically in a number of states in the U.S.
The most severe form of pancreatitis is referred to as necrotizing pancreatitis, which basically means pancreatitis in which the damage is so severe that portions of the pancreas are being killed. Some authors refer to this as hemorrhagic pancreatitis. This form of pancreatitis can be fatal and requires early intervention and aggressive treatment when it is present. Dogs with necrotizing pancreatitis usually look severely ill and are usually in obvious pain or extreme discomfort. Cats are extremely depressed and won't eat but may not show much else even though the pancreatitis is very severe.
Perhaps the greatest roadblock to diagnosis of pancreatitis in cats is simply recognizing that it might be present. Cats are much better at hiding the pain and other symptoms of pancreatitis than dogs and it is very likely that the number of cats who have pancreatitis far exceeds the number of cats who are expected of having it --- meaning that very often no one looks for the disease even though it is present. The other great roadblock in diagnosing pancreatitis in cats has been the lack of a single really good test for this disease.
Radiographs and ultrasound examination are both less useful in cats than in dogs for diagnosing pancreatitis. Even very good ultrasonagraphers have difficulty identifying pancreatitis in cats, although the diagnosis is likely to be correct if standard guidelines for diagnostic criteria are followed and it can be made. X-rays really provide very little information about the possibility of pancreatitis in cats.
Routine blood counts and blood chemistry analysis in cats is also less helpful than in dogs. Amylase and lipase values in cats do not seem to correlate well with pancreatitis. Serum chemistry values tend to be normal in cats with pancreatitis. If the liver associated enzymes (alkaline phosphatase, ALT) are high in an older cat it is reasonable to suspect that pancreatitis might be present just because liver disease and pancreatitis occur at the same time fairly commonly in cats. Trypsin-like immunoreactivity (fTLI) testing could detect pancreatitis with good reliability but was not a very sensitive test for the condition. Cats with severe pancreatitis may have low serum calcium levels. This can be a significant finding from a prognostic standpoint, as very low calcium levels are associated with a poor prognosis in cats.
Recently the Texas A&M Gastroenterology Laboratory has been able to develop a feline pancreatic lipase immunoreactivity test for cats (fPLI) and this test is more sensitive and as specific as the trypsin-like immunoreactivity test. This test is currently the best available test for pancreatitis in cats.
Biopsy of the pancreas can also be used to determine if pancreatitis is present and is a useful test when it is possible to obtain pancreas tissue samples. This is sometimes done when obtaining liver biopsy or intestinal biopsy samples from cats who are exhibiting signs of more than one disease, especially the "triad syndrome" cats who have all three problems at the same time.
One point important to note about laboratory testing for pancreatitis in cats is that amylase and lipase levels rise in many cats with chronic renal failure and in some cats rises in these enzymes are the first sign that the kidney function is not sufficient for all daily needs. Many cats with rises in these enzymes as an early indicator of renal disease have no other clinical signs and the amylase or lipase rise is found in routine lab work done for presurgical purposes or for other routine reasons. It is easy for a veterinarian who is used to seeing pancreatitis in dogs to assume that the increase in amylase or lipase in a cat may indicate pancreatitis, especially if he or she is unaware of the potential for rises in these enzymes due to kidney failure.
It is much harder to figure out how to treat cat with pancreatitis than dogs. If the cat has classic signs of pancreatitis such as vomiting and abdominal pain it can pretty much be treated in the same way as dogs are, pain relief and fluid therapy. Most cats with pancreatitis have much more subtle signs and it is much harder to decide the optimum therapy for them.
I suspect that many more cats have pain from pancreatitis than show this pain. I think it is best to just assume that pain is present and to attempt to use pain control if pancreatitis is suspected, especially acute pancreatitis. Unfortunately, the choice of appropriate pain relievers is smaller for cats than for dogs. It is possible to use fentanyl patches (Duragesic Rx), tramadol (if oral medications can be used), buprenorphine, constant rate intravenous infusion of ketamine or morphine (must be done carefully in cats) or butorphanol (Torbutrol, Torbugesic SA Rx).
Cats also benefit from fluid therapy but do not seem to have quite as much problem with electrolyte disturbances as dogs do. Despite this, it is a good idea to monitor electrolytes as low potassium and low calcium levels can be serious concerns in cats with pancreatitis.
In dogs there does not seem to be much use for corticosteroids but in cats they may be essential to control pancreatitis induced by inflammatory bowel disease or cholangiohepatitis. If this is the case there are usually no problems with using corticosteroids even though pancreatitis is present. Some veterinarians believe that pancreatitis is an immune mediated disease in cats and that there may be direct benefits to the pancreas from the use of corticosteroids but this is uncertain.
Cats get into trouble when they don't eat much faster than dogs. Any cat who appears to have pancreatitis and who has not been willing to eat for more than 48 to 72 hours should probably have a feeding tube placed and should be fed through the tube. For temporary feeding a nasogastric tube is sufficient but for longer term feeding it is necessary to consider an esophageal, gastric or jejunal feeding tube, all of which require surgical implantation of the tube. This is another situation in which it can be very helpful to consider asking for referral to a critical care facility as they are much more likely to place a feeding tube and to maintain the tube until it is clear that the risk of secondary hepatic lipidosis (a form of liver disease) is over. This point is reached when the cat will readily take foods in orally on its own.
It is critically important to remember that pancreatitis in cats must be recognized to be treated. Whenever a cat has inflammatory bowel disease or increases in liver enzymes it is necessary to consider the possibility that pancreatitis may be present. This is especially true when treatment for liver disease or IBD is not going as well as is expected.
Cats seem to benefit from control of any contributing or concurrent illnesses, such as inflammatory bowel disease or cholangiohepatitis. It is unclear whether or not there is any benefit to dietary changes in cats, other than those that may benefit concurrent illnesses. In another instance of having to rely on unproven medical therapies, there does seem to be benefit for some cats from the use of low doses of prednisone to prevent future occurrences of pancreatitis. There is a very good chance that the major benefit may be due to effects on the intestinal tract and liver and it may be more important to consider this therapy in cats with IBD or cholangiohepatitis than for pancreatitis that seems uncomplicated. It is very likely that weight control has a place in preventing future attacks of pancreatitis in cats but this is also not well documented at this time. Cats with either inflammatory bowel disease or pancreatitis can be deficient in Vitamin B12 (cobalamin). Supplementing this vitamin through periodic injections may be very beneficial for some cats. Oral administration of cobalamin doesn't seem to work as well. This information is relatively new in veterinary medicine but can be found in the new edition of the "Textbok of Veterinary Internal Medicine" if your vet needs a reference for the rationale and dosing requirements.
Dr Michael Richards. DVM 9/2005
Q: Dear Dr. Mike: My cat has had 2 bouts of pancreatitis. The first time, she was treated for inflammatory bowel disease. The second time, an ultrasound revealed that her pancreas was inflamed, so they were better able to diagnose the problem. She seems healthy now, but she still vomits occassionally (not more than once a month). Is pancreatitis a recurring problem? Should I rush her to the vet each time she vomits? I think the vet said that even the scent of food at the time would cause the pancreas to react. Should I remove food and water when she vomits? Do you know where I could get more information about the disease?
A: Pancreatitis is hard to definitively diagnose in cats. Therefore, it is not as well described as pancreatitis in dogs. Acute pancreatitis seems to be rare in cats but pancreatitis does seem to occur chronically in cats, probably much more often than we realize.
Pancreatitis in cats is signaled by a reluctance to eat, vomiting, jaundice and weight loss. There is an association between feline infectious peritonitis (FIP) and chronic pancreatitis in cats so an effort to discern if this is a problem may be a good idea. Toxoplasmosis has also been implicated as a possible contributing factor in chronic pancreatitis in cats so testing for this may also be worthwhile, especially since it is more treatable than FIP.
During the acute illness it can be beneficial to use pain relieving medications. Pancreatitis is pretty painful in dogs and they seem to do much better with pain relief. It is likely the same is true in cats. The use of Fentanyl (Rx) patches has made chronic pain relief easier to accomplish in cats. If there are signs of dehydration or lethargy it is probably beneficial to use intravenous or subcutaneous fluid therapy (there is some indication that IV fluids are better in these types of illnesses). If the pancreatitis is causing a cat not to eat it may be necessary to use parenteral feeding techniques such as a feeding tube surgically implanted into the intestines after the portion which the pancreas empties into.
This is a tough condition to deal with. Low fat diets are supposed to be helpful for long-term control. If your cat will accept a lower fat diet this would be a good thing to consider.
Mike Richards, DVM
Q: Dear Dr. Mike: I wanted to thank you for your helpful information and comforting words. I do appreciate it very much. I know you must be very busy, but could you please clarify one thing for me? You said that it was extremely unlikely that anything the emergency clinic could have done would have changed the outcome for Spook. If I had brought him in at the first signs he was not well (lethargy and dehydration) that night, would a cat in that condition, showing no other symptoms, be given any kind of treatment that stops the progress of pancreatitis when they did not know that was what he had? Or would they have given him a generic treatment/standard procedure that would not have done anything to help. (Again, my vet said he did not show any clinical signs and he did not know what Spook had until a day and a half later when he operated on him.) I am sorry for being a bit obsessed with answers, but for me it is the only way I will be able to put my mind to rest and begin the healing process of losing such a big part of my life. Thank you again.
A: The great difficulty identifying pancreatitis in a cat leads me to believe that it would have been unusual for the emergency clinician to identify pancreatitis even if Spook had gone in earlier. So I think that just standard treatment for the symptoms noted would have been instituted. That may have been OK for pancreatitis since the treatment is to control any symptoms you can and then wait for it to heal. But the odds are that symptomatic treatment would not have been sufficient to change the course of the disease. There is a small amount of evidence suggesting that high volume fluid therapy may be helpful in pancratitis in limiting the blood clotting effects and ischemia (tissue death due to lack of blood flow) in dogs but there are more accurate tests for dogs and for some reason they seem to convey the location of pain better than cats, which is very helpful in diagnosing pancreatitis. With a high degree of confidence in the diagnosis, administering large fluid volumes IV may be OK. It is just hard to get to a high degree of confidence that pancreatitis is the problem in a cat. I really hope that we will resolve this confusing situation in our cat patients sometime soon. It is frustrating to have to guess about so important a problem.
Mike Richards, DVM
Last edited 04/12/07
Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...