If your dog is showing signs of vomiting, abdominal pain, and loss of appetite, there is a very likely chance that you will simply shrug these manifestations as nothing more than indications of an upset stomach and that the condition will sooner or later pass without any further untoward incident.
Unfortunately, you may miss other signs and symptoms that should have already warned you about the possibility of acute pancreatitis in your dog. These can typically include generalized restlessness and a guarding behavior directed at immobilizing its tummy; as if your pooch will never want to move at all.
There can also be high fever and excessive drooling. And if management doesn’t come fast enough, your dog might go into shock and organ failure typically ensues. Acute pancreatitis is a life threatening and very painful condition. That is why one should be very vigilant in the analysis of the various symptoms associated with the disease so you’ll know how to manage it.
First, the Pancreas
This organ is both an endocrine and a digestive organ since it produces a variety of hormones needed for the metabolism of carbohydrates in the body and enzymes and fluids needed for the proper digestion of carbohydrates, fats, and proteins. It is an elongated organ that is located just underneath the liver.
- As an endocrine organ
The pancreas produces the hormones insulin and glucagon which are responsible for the utilization and storage of glucose. Glucagon is produced by the alpha cells of the pancreatic Islet of Langerhans while insulin is produced by the beta cells of the Islet of Langerhans.
Insulin is the carrier molecule upon which glucose is moved from the blood and into the cells for use as energy. Any excess is converted into glycogen in the liver and in muscle tissues as well as into triglycerides for storage into adipose or fatty tissues. In effect, insulin is what lowers the level of sugar or glucose in the blood.
On the other hand, glucagon is activated if the body senses that its cells require energy in the form of glucose. However, because there is no readily available sugar derived from meals, it stimulates the conversion of glycogen that has been stored in the muscle cells and in the liver into glucose. At the same time, glucagon stimulates fatty tissues to start burning stored triglycerides as a form of energy for the cells. As such, if the body needs sugar and yet mealtime is still several hours away, glucagon is there to provide the glucose for energy from stored glycogen and triglycerides.
- As a digestive organ
We know that the food that our dogs eat will be digested initially in the stomach, turning it into one giant ball of mulch known as chyme. This chyme is then pushed towards the dog’s small intestines in the region of the duodenum where final digestion and initial absorption take place.
In the duodenum, there is a tube that connects it to the pancreas as well as the gall bladder and the liver. Together, these 3 organs are known as the accessory organs of digestion because, while they are not technically a part of the lengthy digestive tract, they play a very important role in the digestion of food molecules present in chyme.
The pancreas secretes pancreatic juice that contains bicarbonate ions which help neutralize the acidity of the chyme. You see, the walls of the small intestines are not as acid-proof compared to the walls of the stomach. As such, the bicarbonate ions help to negate the acidic nature of chyme and lay the foundation for a more efficient functioning of the pancreatic enzymes.
Pancreatic enzymes are chemicals that are produced by the pancreas to help break down larger molecules into their component pieces. These typically include the following.
- Pancreatic amylase – This enzyme breaks glycogen and starches into glucose, maltotriose, and maltose. This allows the small intestines to absorb these nutrients, with the exception of maltose which still has to be broken down into component glucose molecules through the action of maltase.
- Pancreatic lipase – This pancreatic enzyme is responsible for digesting triglycerides and turning them into monoglycerides and fatty acids. Unfortunately, it is not easy to digest triglycerides. That is why bile from the gall bladder must be included into the chyme to emulsify the triglyceride molecules, allowing the pancreatic lipase to dissolve its chemical bonds.
- Carboxypetidase, trypsin, and chymotrypsin – These three enzymes are needed for the digestion of large protein molecules and peptides into their respective amino acid subunits. Once absorbed into the bloodstream, these amino acids are rearranged to form peptides and proteins again.
- Deoxyribonuclease and ribonuclease – Nucleic acids found in dog food are digested by deoxyribonuclease and ribonuclease. DNA molecules are digested by deoxyribonuclease to produce deoxyribose, a sugar, and the 4 nitrogenous bases known as adenine, thymine, guanine, and cytosine. On the other hand, ribonuclease break RNA molecules into their corresponding sugar and nitrogen bases namely ribose and adenine, guanine, uracil, and cytosine, respectively.
The pancreatic enzymes may not be as acidic as the gastric juices found in the stomach. However, this does not mean that they are not very powerful substances. Otherwise, how can they break large molecules into their component parts if these substances are weak?
Another point that you simply must understand is that these pancreatic enzymes are released into the duodenum only in the presence of food or chyme. That means, if there is no chyme in the small intestines, the pancreas will not be releasing these enzymes.
What Happens in Pancreatitis?
We know that the pancreas is involved in two fundamental physiologic functions: the formation and release of glucagon and insulin and the synthesis and secretion of pancreatic enzymes. The problem in pancreatitis is that, as the term implies, there is inflammation of the tissues that make up the pancreas. The inflammatory changes stimulate the release of the enzymes even in the absence of food or chyme in the small intestines.
Remember what we said about pancreatic enzymes being released only in the presence of chyme in the duodenum? In pancreatitis, these juices or enzymes are inadvertently released even though there is no food in the duodenum. Another major issue is that the enzymes are actually not released into the duodenum. Instead, they are activated within the pancreas itself.
We have already explained just how powerful these enzymes are as they are fully capable of breaking down polypeptides, starches, triglycerides, and many more into smaller component sub-units. If these enzymes can do this to an acidic chyme, what more to the tissues of the pancreas itself?
In other words, the major problem in pancreatitis is that enzymes are released and activated through some specific mechanism. Owing to the very nature of these enzymes, they slowly ‘eat up’ or ‘digest’ the tissues of the pancreas leading to significant damage. This is what causes extreme pain in your pooch.
What are the Symptoms of Canine Pancreatitis?
Pain is not the only clinical manifestation associated with pancreatitis. It should be recalled that the pathology is more like the pancreatic enzymes are digesting the pancreas itself instead of the proteins, fats, and carbohydrates present in chyme in the duodenum. It is for this reason that the clinical presentation of pancreatitis in dogs can typically be manifested by the following.
- Repeated vomiting
- Loss of appetite
- Hunched back appearance
- Distended abdomen
- Abdominal pain
- Lethargy or weakness
Repeated vomiting is believed to be brought about by the stimulation of visceral afferent nerves located in the bile ducts as well as the duodenum secondary to irritation of the intestinal mucosa. Vomiting signals are sent to the medulla oblongata of the brain. Other experts also say that the vomiting is triggered by the activation of chemoreceptors in the presence of toxins freed by the severely damaged pancreas and surrounding organs.
Diarrhea results from irritation of the intestinal mucosa, leading to a faster transit time of the chyme through the gastrointestinal tract.
The hunched back appearance is considered more as a guarding behavior in an attempt by the dog to limit the movement of its abdominal region since even the slightest movement can bring sharp pain. The same is true with a distended abdomen.
Dehydration is a natural consequence of excessive diarrhea although other mechanisms can also be at play. Fever is almost always an indication of inflammatory reactions occurring at the tissue level. The loss of appetite is directly related to the pain experience. One really cannot entice a dog to eat if it is in severe pain. The more that your dog doesn’t eat, the weaker or more lethargic it gets.
It should be clear that these are just some of the classic signs of canine pancreatitis. The point is that if you notice any of these manifestations, albeit infrequently, you need to keep a watchful eye on your pooch. However, if you note several manifestations occurring at the same time or they occur quite repeatedly, a trip to your veterinarian should be a priority.
What Causes Canine Pancreatitis?
The exact pathophysiology of canine pancreatitis is not yet fully understood although it is believed that it closely mimics the pathophysiologic process involved in the development of pancreatitis in humans. That said, the main pathology is more related to the presence of both intracellular and extracellular factors that result in an imbalance in cellular homeostasis. Aside from these two factors, experts also believe that canine pancreatitis can be brought about by ductal cell injury. Here is a list of the possible causes of canine pancreatitis.
- Regular consumption of high-fat diet or unusually high fat content ‘feast’
- Canine obesity
- Diabetes mellitus in dogs
- Administration of a variety of medications such as cholinesterase inhibitors, vinca alkaloids, phenobarbital, azathioprine, potassium bromide, thiazide diuretics, calcium, estrogen, levo-asparaginase, and estrogen
- Severe blunt trauma to the abdominal region
- History of canine dietary indiscretion
Let us take a moment to analyze one of the most common causes of canine pancreatitis: high fat diet. This has something to do with the formation of gallstones. This is one of two leading causes of acute pancreatitis in humans, with the other being alcohol consumption. Since dogs do not consume alcohol, experts believe that the formation of gallstones is the primary mechanism in the development of canine pancreatitis.
When it comes to the formation of gallstones, regular consumption of high fat diet is mostly to blame. It is a well-documented fact that majority of gallstone cases are due to the accumulation of excessive amounts of cholesterol in the bile. Since the gallbladder is connected to the pancreas via the common bile duct, pancreatic enzymes cannot pass through this portion of the duct near the entrance to the brush borders of the duodenum. Since the duct is blocked by gallstones, the pancreatic enzymes are pushed back towards the pancreas where they produce the characteristic inflammatory changes.
Studies have shown that this ‘backflow’ of pancreatic enzymes can lead to disturbances in the microcirculation of the pancreas. Additionally, microvesicles are shown to develop in both the acinar and islet cells of the pancreas. There is also swelling of the mitochondrion, dilatation of the rough endoplasmic reticulum, and gross modification of the endothelial cells of the blood vessels of the pancreas. All of these histologic changes are believed to be the result of oxidative stress on pancreatic cells leading to pancreatic injuries and tissue damage. This initiates the inflammatory cascade and the resulting clinical manifestations typically seen in canine pancreatitis.
Do take note that gallstone formation does not only occur with regular consumption of a high fat diet. Even seasonal or occasional consumption of unusually high fat food can lead to the formation of gallstones, precipitating canine pancreatitis. This is especially a concern during the holidays where we often give our pooches with several servings of our own food. Unfortunately, we often forget that the food we feast on during the holidays are unusually high in fat.
Other causes of canine pancreatitis, as we have already listed above, include trauma to the abdominal region especially in the area where the pancreas is located. Traumatic injuries lead to tissue destruction including the release of pro-inflammatory substances. These can stimulate the same histologic changes seen in a gallstone-initiated pancreatic inflammation.
Is there a Difference Between an Acute and Chronic Pancreatitis?
You may have already heard some people talk about acute and chronic pancreatitis in dogs. In medical parlance, an acute illness is typically any condition that lasts less than 6 months in duration. Anything that lasts longer than that is already considered as chronic. However, this is an oversimplification of the actual difference in these conditions. While they do have a difference in time element, it is not the only parameter upon which they are differentiated.
- Acute canine pancreatitis
The onset of an acute pancreatitis is often sudden, without warning. The clinical manifestations are usually more severe and are considered to be life threatening especially if the resulting tissue inflammation in the pancreas spreads to other organs.
- Chronic canine pancreatitis
The clinical manifestations of chronic canine pancreatitis are typically mild; in some cases they are absent. The condition develops slowly over time. It is often brought about by a lingering subclinical pancreatitis or several episodes of clinical acute pancreatitis.
How Will My Vet Know that My Dog Has Pancreatitis?
Diagnosing canine pancreatitis based on the presenting signs and symptoms alone can be quite tricky since these can often indicate other problems as well. For instance, diarrhea, dehydration, and fever are also common in infections of the gastrointestinal tract or even a simple stomach upset. Weakness or lethargy can also be brought about by causes other than canine pancreatitis. As such, it is very important for you to bring your pooch to your veterinarian if you observe several of these clinical manifestations occurring more frequently than is comfortable.
- Comprehensive health history including medical history
An examination of the overall health of your dog is crucial to the formulation of an accurate diagnosis. Since some of the causes of canine pancreatitis involve some faulty dietary patterns, trauma to the abdominal area, and exposure to toxins and harmful medications, among others, it is crucial that these pieces of information be elucidated in the health history of your dog.
- Focused physical examination
Your vet will be concentrating most of his physical assessment of your dog in the abdominal region. Tests for abdominal tenderness will be performed while other organs such as the heart and the lungs are also assessed. This is because of the direct relationship between tissue injury and the stimulation of the stress response whereby changes in normal cardiovascular and pulmonary mechanisms can be readily seen.
- Blood tests
These kinds of tests will determine for the presence of nutritional imbalances since pancreatic enzymes do not necessarily reach their destination in the duodenum. Also, the levels of pancreatic enzymes as well as enzymes emanating from the liver will also be determined. Your vet may also require an examination of insulin levels as well as calcium levels in the blood of your dog since the latter is known to be a major precursor to the development of pancreatitis. Electrolytes will also be evaluated especially if your dog has been vomiting or passing loose watery stools for quite some time now.
- Diagnostic examination
Imaging tests will be performed to determine the extent of the tissue damage in the pancreas. Typically, ultrasound or radiograph is used to help rule out the possibility of other causes of the inflammation seen in the pancreas. These imaging tests also reveal the extent of the inflammation, whether it has already encroached into other organs in the abdominal cavity or not yet.
- Pancreatic fine needle aspiration
In this test, a large needle is inserted through the skin of your dog and passed right through the pancreas. A small sample of pancreatic tissue is aspirated and sent to the laboratory for further histological examination. This will also help rule out the possibility of pancreatic cancer which has a lot in common, as far as clinical manifestations are concerned, with canine pancreatitis.
What will be the Treatment Options for My Dog that has Pancreatitis?
As in any other veterinary health condition, a definitive cure is directed towards elimination or management of the cause. That is why it is very important for your vet to determine the cause of the pancreatitis in your dog so that appropriate measures can be instituted to correct this abnormality. For instance, if the cause is determined to be related to the formation of gallstones, then the cure will be the surgical removal of these gallstones.
However, aside from the definitive treatment, you must also consider symptomatic management since these symptoms are what are bringing a lot of concern to you and your dog.
Generally, the short-term management of pancreatitis in dogs includes the following.
- Aggressive intravenous fluid therapy
- Appropriate pain medications
- Antiemetics for vomiting
- Veterinary imposed fasting for 24 hours in an effort to rest the pancreas
- Continuous monitoring of the condition with emphasis on vigilance against deterioration
In the long-term, veterinarians will adhere to the following canine pancreatitis management principles.
- Continuous monitoring of pancreatic enzymes especially lipase and amylase
- Continuous monitoring and strict enforcement of zero-fat intake
- Administration of an ultra-low fat or at least low fat prescription diet for dogs
- Feeding the dog in smaller yet more frequent meals
Can I Prevent Canine Pancreatitis?
Unfortunately, there is no way you can completely prevent pancreatitis in dogs. However, you can at least lower their risk of developing pancreatitis by adhering to the following.
- Manage your pet’s weight; don’t let it become obese
- Steer clear of high-fat doggie diets
- Don’t give your pet pooch table scraps, especially food high in fat
- Don’t allow your pooch to gain access to garbage
- Don’t give your dog any medication or supplement you haven’t discussed with your vet
Pancreatitis in dogs is a serious concern. While there are plenty of possible causes, there are several things that we can actively do something about. For starters, not giving our dogs table scraps and fat-rich foods can help reduce their risk for pancreatitis. Also, maintaining their ideal body weight and avoiding giving them medications without the recommendation of our vet can help us secure a brighter future for our pet dogs.