58 | What happens when the pancreas doesn’t work properly? Let’s take a look…

PodcastGastroenterologyPancreas
Written By Laura Jones

Today, we’re rounding up our little gastrointestinal detour to the pancreas with part 2 of our mini-series on pancreatic disease.

 

In episode 57, we chatted all about pancreatitis, but today, we’re changing things up and talking about what happens when the pancreas can’t help digest and break down food normally—a condition known as exocrine pancreatic insufficiency.

So what is exocrine pancreatic insufficiency, and how does it impact our patients?

Well, exocrine pancreatic insufficiency, or EPI, is exactly what it says on the tin—a failure or insufficiency of the exocrine portion of the pancreas. 

To whisk you back to your student days for just a second with a tiny A&P refresher, the pancreas has two functions - the endocrine functions take place within specialised cells in the pancreatic islets, and the exocrine functions take place within acinar cells. These exocrine cells create and release digestive enzymes, which travel into the duodenum and help break down carbohydrates, fats and proteins.

With EPI, there are not enough functional exocrine cells to create and release enough digestive enzymes. This means our patients cannot properly break down and absorb nutrients from their food, resulting in malabsorption, maldigestion and vitamin deficiencies, such as vitamin B12, K, E and folate. Around 90% of the exocrine tissue is lost before clinical signs develop.

What causes EPI?

There are several causes of exocrine pancreatic insufficiency in dogs and cats, including:

  • Atrophy of the pancreatic acinar cells

  • Chronic pancreatitis

  • Pancreatic masses or masses surrounding the pancreas and causing obstruction of the pancreatic duct

Acinar atrophy is a common cause in German Shepherd Dogs, Rough Collies, Chow Chows, and Eurasians, whereas pancreatic damage secondary to chronic pancreatitis is the most common cause in other breeds of dogs and cats.

We see EPI most commonly in young adult German Shepherd dogs around 1-3 years old. Patients with other causes of EPI (such as chronic pancreatitis) are usually middle-aged to senior cats and dogs of any breed.

Ok, so that’s what EPI is and what causes it. But what signs do we see?

The most common clinical signs reported include polyphagia and weight loss with soft faeces-to-diarrhoea.

As these patients cannot absorb nutrients from their food normally, they eat more, but despite this, they continue to lose weight. They usually present in very poor body condition.

These patients don’t just have diarrhoea - they have very characteristic faeces. 

You can usually tell an EPI patient from a mile off by two things: first, their smell, and second, the colour of their faeces. They tend to pass large volumes of pale, beige-yellow, loose, incredibly smelly faeces. They also have steatorrhea - they pass extremely fatty faeces - due to their inability to digest and absorb dietary fat normally. Rarely, they may pass watery diarrhoea instead.

In addition to their very typical stools, flatulence, borborygmi, coprophagia and pica are also reported.

Patients with EPI usually have skin and coat changes, too. They tend to have a greasy coat (especially around the back end) and seborrhea. 

Despite these changes, they are usually clinically well on presentation and do not tend to require hospitalisation for specific EPI treatment in many cases. Much of our role when treating and nursing these patients is in their diagnosis and long-term care.

How do we diagnose our EPI patients?

EPI is usually diagnosed via a combination of bloodwork and clinical signs, plus additional tests to rule out other extra-GI or gastrointestinal causes as needed.

Routine biochemistry and haematology do not reveal any specific changes with EPI. Amylase and lipase levels are not helpful; sometimes, we can see low cholesterol levels, though these are not exclusive to EPI patients.

It is essential to perform malabsorption testing, including measuring vitamin B12 and folate levels, which are usually low.

Let’s talk about TLI

The most important diagnostic test in an EPI patient is trypsin-like immunoreactivity or TLI. This test is a reliable measurement of pancreatic function and measures blood trypsinogen levels. Trypsinogen is a precursor to trypsin, the pancreatic enzyme that breaks down proteins.

A low TLI is diagnostic for exocrine pancreatic insufficiency. Typically, levels below 2.5 mcg/L in dogs or 8 mcg/L in cats confirm the diagnosis. 

TLI levels can be challenging to interpret in patients with chronic pancreatitis since pancreatitis can actually increase TLI levels. If the patient has a borderline result, retesting at a later stage or trialling treatment may be considered.

Other tests commonly performed include faecal analysis and additional testing for gastrointestinal disease, such as diagnostic imaging where required (though this does not show any specific changes in EPI patients and may instead be used to investigate other causes of chronic GI signs).

Ok, so our patient has EPI. How do we treat them?

Well, the good news is that treatment is simple - we need to replace those pancreatic enzymes they’re not creating themselves!

Exogenous (external) pancreatic enzymes are available in various forms, including tablets, capsules, uncoated powdered enzymes and even raw pancreas. There has been much debate about which form of pancreatic enzymes is best, with some suggestion that uncoated powdered enzymes (e.g. Panzym powder) are superior to other formulations.

Whatever form you use, it must be added to every meal because, without it, the patient will struggle to digest and absorb nutrients.

Up to 82% of patients with EPI are also hypocobalaminaemic, so it’s essential we supplement vitamin B12 levels, too. This is usually achieved parenterally via subcutaneous injection to begin with because our patients can’t break down and digest enteral supplementation until their condition improves. Once they have stabilised, they are transitioned to oral supplementation (e.g., Cobalaplex).

And what about feeding these patients?

It’s not just about helping them digest their food—we also need to think about WHAT we’re going to feed them. Supplementation with digestive enzymes does not completely ‘fix’ digestion—particularly fat digestion—and this means we’ll need to modify our patient’s diet, too.

Previously, we commonly fed low-fat diets to EPI patients. Whilst this was once considered the ‘norm’ for EPI, it can be counterproductive as these diets are often lower in calories, and fat restriction can cause deficiencies of fat-soluble vitamins or essential fatty acids.

Instead, we generally opt for highly digestible, moderate-fat, low-fibre diets, depending on the individual patient. Regular nutritional assessment is vital because we want to see improvements in the patient’s body weight and body condition score as treatment continues.

Veterinary nurses and technicians are ideally placed to support the patient after starting treatment, especially since nutrition plays such an essential part in our role. We should work with our veterinary surgeons to monitor and support these patients after diagnosis, assessing them regularly and providing advice and support as needed.

So there you have it! That’s a super quick dive into exocrine pancreatic insufficiency - a common cause of malnutrition, especially in dogs. These patients might not be super sick or unstable at presentation, but that doesn’t mean we don’t have a role in their care as nurses - with nutritional assessment, planning, guidance and support absolutely vital for their recovery.

Have you ever seen an EPI patient before? How did you manage them? How did they present? Drop me a DM on Instagram and let me know - I love hearing about the patients you’re seeing and the skills you’re using!

Did you enjoy this episode? If so, I’d love to hear what you think. Take a screenshot and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!

References and Further Reading

Laura Jones
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57 | 3 things you can do to give better care to your pancreatitis patients right now