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Pancreatic exocrine insufficiency (PEI) means that your body has difficulties digesting food properly — this leads to a range of uncomfortable symptoms, including diarrhoea, wind, bloating, stomach pain, smelly/oily stools, unexpected weight loss and tiredness.1
What is PEI?1
In people with PEI, or pancreatic exocrine insufficiency, the pancreas doesn't make enough digestive enzymes to adequately break down food into its smaller absorbable components.
This means your food passes through your digestive system before all the essential nutrients and energy you need can be taken up and used or stored.
What does the pancreas do?1
The pancreas is one of the many organs in your digestive system. It’s tucked away behind your stomach and connected to the first part of your small intestine (the duodenum).
The pancreas plays two important roles in your body, it produces:
- Powerful digestive enzymes that chemically break down the fats (lipases), carbohydrates (amylases) and proteins (proteases) in your food – this is its exocrine role.
- The hormone insulin that helps regulate your blood sugar levels – this is its endocrine role.
Understanding digestion3
Digestion is a process that takes place in your gut (or gastrointestinal system) and involves different organs such as the gallbladder, liver and the pancreas.
The gut is a long tube that stretches from your mouth to your anus and along the way there are specialised sections where the different parts of digestion take place.
When food passes from your stomach into the small intestine, signals are sent to the pancreas to produce digestive enzymes.
- Digestion starts in the mouth where food is chewed and mixed with the enzymes in your saliva.
- Food travels down to your stomach where it is further broken down by digestive juices (a mixture of acids and more enzymes).
- Next, food passes from your stomach into the small intestine – and the pancreas is signalled to start producing its digestive enzymes. These enzymes are delivered into the small intestine through small tubes called ducts.
- Your small intestine is made up of three sections:
- The duodenum (first section) is where most of the digestion of food takes place, with the help of enzymes from the pancreas and bile from the liver and the gallbladder – this is where fats, carbohydrates and proteins are broken down into smaller molecules (nutrients).
- The jejunum (middle section) and ileum (final section) is where most of the nutrients are absorbed into your bloodstream through the gut wall.
- The large intestine is the last part of your gut and is made up of the colon and the rectum. Most of the water is absorbed in this part of the gut and the remaining waste material is compacted ready to be passed out of the body.
How does PEI affect digestion?1
Before we can get any benefit from the food we eat, it has to be broken down.
If not enough digestive enzymes are produced by the pancreas, or they are not able to work properly, then our food cannot be properly digested. This leads to the uncomfortable digestive symptoms experienced by people with PEI.
Eventually, as PEI progresses and the essential nutrients (including vitamins and minerals) cannot be absorbed and transported to where they are needed, potentially resulting in serious nutritional deficiencies.
What causes PEI1
Pancreatic exocrine insufficiency can occur due to the following reasons:
- Damage to the pancreas tissues leading to reduced ability to produce digestive enzyme
- Enzymes cannot reach the food in the intestines due to blockage of ducts
- Surgery can change the anatomy so that the enzymes cannot reach the food in the intestine
- Damage to the mechanisms which signal the pancreas to release enzymes after a meal
PEI can develop in anyone who has a medical condition or who has undergone a procedure that affects the pancreas or prevents the release of its digestive enzymes.
- Smith RC, et al. Australasian guidelines for the management of pancreatic exocrine insufficiency. Australasian Pancreatic Club, October 2015.
- Better Health Channel. Pancreas. Last updated: August 2014. Available at: https://www.betterhealth.vic.gov.au/health/ConditionsAndTreatments/pancreas (accessed 10/5/19).
- NIH. Your Digestive System & How it Works. December 2017. Available at: https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works (accessed 10/5/19).
