Exocrine pancreatic insufficiency (EPI)

Almost all dogs will suffer from diarrhoea at some point in their lives. In most cases this lasts no more than a few days and dogs generally get better without any treatment. However, in a few cases the diarrhoea is due to a more serious underlying cause and does not resolve. EPI is one of the conditions that can result in chronic diarrhoea.

EPI results in a reduced ability to digest food this means that an affected pet will suffer from chronic diarrhoea and be significantly underweight. Dogs with EPI have a good appetite but despite consuming lots of food they are literally starving.

The pancreas is a small organ located close to the stomach. It has an important role in the digestion of food and produces large volumes of digestive enzymes after each meal, which are released into the gut to help digest food as it leaves the stomach. These enzymes are normally stored in specialised storage granules in the pancreas until they are needed.

In EPI the pancreas is not able to produce sufficient quantities of these enzymes and so food is poorly digested. The undigested food cannot be absorbed into the body and passes through the gut resulting in the production of smelly greasy faeces. Despite consuming plenty of calories the dog is only able to use a small fraction of these and the rest pass out unused in the faeces.

The pancreas also has a second, and completely separate, function which is to produce the hormone insulin which helps to control levels of blood sugar. It is unusual for pancreatic damage to be so severe as to cause loss of this function along with EPI.

In certain breeds, e.g. German shepherd dogs, collies and English setters, the condition is hereditary (passed from parents to their puppies) although the parents may not show any outward signs of EPI. EPI occurs due to atrophy (shrinking or withering away) of the pancreatic tissue. There is a hereditary component to the disease but factors for the disease developing are considered multifactorial. Recent studies suggest that the immune system plays a role in destroying the pancreatic cells. In a few animals EPI may develop in later life as a consequence of long term pancreas damage due to pancreatitis.

The most obvious sign of EPI is weight loss over several months despite an increased appetite. Faeces are bulky and they may be greasy or smelly and diarrhoea is common. In most cases dogs appear to be well in themselves although the haircoat may be poor. In some animals there is a history of previous pancreatitis (abdominal pain, vomiting and diarrhoea).

Your vet may suspect that your dog has EPI from the clinical signs. However, there are lots of other diseases that cause weight loss and diarrhoea and many investigations may be necessary. Diagnosis can be confirmed by blood tests.

Fortunately the management of EPI is relatively straightforward (at least in theory). If the disease is the consequence of an insufficient production of digestive enzymes then the treatment should be to supplement these enzymes. The enzymes are available as a powder or enteric coated capsules.

Dietary changes may be necessary to restrict the fat in the diet with additional triglyceride supplementation. Improvements in consistency of faeces should be seen within a few days of treatment although it may take several months for weight and appetite to return to normal.

In some cases short courses of antibiotics are also required to stabilise the bacterial population in the intestines. When untreated EPI results in a large amount of undigested food in the bowel and this allows the bacterial population in the bowel to flourish which can also affect bowel function.

In most dogs it is possible to manage the signs of EPI to allow dogs to regain and maintain their body weight (and maybe even put on some weight). However, the underlying problem will never go away and if diagnosed your pet will require treatment for the rest of its life. It is important to consider the cost implications of this when embarking on treatment initially.

If you have any concerns about your dog contact your own vet for further advice.