Exocrine pancreatic insufficiency in dogs

The underappreciated pancreas is perhaps one of the most important organs in the body as its production of hormones and digestive enzymes are critical to survival. However, damage to the pancreas can now be treated to allow dogs to live full, healthy lives.

The pancreas has both endocrine and exocrine functions. The endocrine functions are production of important hormones such as insulin, which happens in small groups of cells called islet cells. The exocrine functions include production and release of digestive enzymes into the small intestine. The exocrine cells in the pancreas are known as acinar cells.

These enzymes are grouped by what sort of substrate they act on; lipases digest fat, proteases digest protein and amylases digest starch. These enzymes are necessary for proper digestion and absorption of nutrients from the diet.

A significant amount of enzymes exists in the pancreas, so as long as 10% of the pancreatic acinar cell function remains, a dog will be able to digest food. Once the amount of enzyme produced drops below that, the dog is unable to properly digest food and meals pass through the animals without any of the valuable nutrients being absorbed. This is known as exocrine pancreatic insufficiency (EPI) and the dog can quickly become malnourished even though it is eating proper meals. Affected dogs rapidly lose weight and develop large volume diarrhea (often oily and extremely malodorous). These dogs shed weight so rapidly that they are frequently mistaken for animal neglect cases.

Dogs can develop EPI in two different ways. Pancreatic acinar atrophy (PAA) is a congenital condition in which the dog’s immune system attacks the acinar cells. Selective destruction of the acinar cells results in dogs showing signs of EPI usually by two years of age. This is seen most often in German Shepherds and Rough-Coated Collies, but other breeds have been affected as well.

Any breed can develop EPI as a result of pancreatic damage. Chronic pancreatitis (inflammation of the pancreas) can result in destruction of enough acinar cell to cause EPI. Loss of blood flow to the pancreas, abdominal infection, or bile-duct obstruction can all cause EPI as well. Unfortunately for these animals, the endocrine function of the pancreas can also be affected and a dog can end up suffering from EPI and diabetes at the same time. Affected animals are also likely to have vitamin deficiencies and changes in the microbial population in the intestines that further complicate treatment.

Veterinarians have several tests available for diagnosis of EPI.  Animals experiencing rapid weight loss and diarrhea are likely candidates for testing, especially if they are a part of commonly affected breeds. A fecal test can also act for screening, but does not confirm the disease. For confirmation, a canine trypsin-like immunoreactivity (cTLI) test is performed.

Since regrowth of the acinar cells does not occur, dogs affected by EPI will require lifelong treatment. The good news is that management of the disease is successful and will result in a happy and healthy animal. Treatment is accomplished through replacement of the enzymes through a powder or tablet. The powder is the most commonly used and is applied to each meal prior to feeding. The powder contains the enzymes necessary for the dog to digest and absorb nutrients from meals and the dose is adjusted based on the dog’s needs and dietary changes.  Successfully managed dogs will recover to a healthy weight over a period of weeks or months and experience full, healthy lives thereafter.

For information on Neogen’s animal safety solutions for EPI, click here.

This blog was written by Neogen’s professional services veterinarian, Dr. Joe Lyman.