Exocrine pancreatic insufficiency: a glossary of terms

Exocrine pancreatic insufficiency (EPI) occurs when the pancreas can't synthesize digestive enzymes, or synthesizes too few enzymes. It can also happen when a blockage or other disruption prevents these enzymes from reaching the digestive tract.

Without these digestive enzymes, the body cannot properly break down foods that move through the digestive tract. This can lead to a number of uncomfortable symptoms, including abdominal pain, gas and bloating, constipation, diarrhea, and fatty stools. It can also lead to unwanted weight loss and malnutrition.

As with many health conditions, it helps to have an understanding of what’s going on in the body when you have EPI. One place to get started is the common terms and phrases that often appear in patient education materials.

Pancreatic enzymes

The pancreas is an organ located behind the stomach and connected to the small intestine. The pancreas plays an essential role in digestion and metabolism by producing digestive enzymes and a hormone called insulin.

• Enzyme. Enzymes are biological catalysts, which trigger biochemical reactions in the body. Most enzymes are proteins.
• Insulin. A hormone produced by the pancreas that helps the body regulate blood glucose levels (blood sugar levels).
• Amylase. A digestive enzyme that is synthesized and secreted by the pancreas. Its primary function is to break down carbohydrates and convert them into glucose, which the body can use as energy.
• Lipase. Another pancreatic enzyme. This one helps break down fats.
• Protease. A third digestive enzyme produced in the pancreas, which helps break down proteins.
• Pancreatic enzyme replacement therapy (PERT). This is the mainstay of treatment for EPI. This medication comes in the form of pills that provide the pancreatic enzymes that the body needs to break down food.

Conditions related to EPI

EPI typically occurs as a result of other health conditions such as chronic pancreatitis, cystic fibrosis, pancreatic cancer, and others.

• Chronic pancreatitis. A condition where there is ongoing inflammation of the pancreas. It can lead to permanent disruption in pancreatic functions. Alcohol use disorder is a common cause.
• Cystic fibrosis. A condition that results in mucus becoming thick and sticky which can cause blockages in many parts of the body, including the pancreatic ducts.
• Pancreatic cancer. Cancer that begins in the pancreas. Most cases of pancreatic cancer begin with abnormal, fast-growing cells in the glands that produce pancreatic enzymes.
• Celiac disease. An autoimmune disease that causes damage to the small intestine when gluten is consumed.
• Diabetes. A disease that occurs when your body is unable to produce enough insulin or use insulin. Insulin is a hormone made in the pancreas that regulates blood sugar levels.
• Inflammatory bowel disease (IBD). This refers to ulcerative colitis and Crohn’s disease, two conditions that cause recurring, painful inflammation in the GI tract.

Weight-loss (bariatric) surgery is also a common, well-known cause of EPI.

Tests to diagnose EPI

There are three main tests that are used to measure how well the pancreas is functioning. These tests may be used to diagnose EPI. Diagnosis may also involve CT scans and ultrasounds.

• Fecal elastase test. One of the three main tests used to diagnose EPI. It measures the amount of elastase in your stool. Elastase is a pancreatic enzyme that helps break down fats, proteins, and carbohydrates. When the pancreas is healthy, elastase is passed into the stool.
• Fecal fat test. Another one of the three main tests used to diagnose EPI. This test shows the amount of fat in the stool, which helps determine how well the body is absorbing fat.
• Direct pancreatic function test. A test to determine how well the pancreas responds to a hormone called secretin, which helps the pancreas release digestive enzymes.
• CT scan. A diagnostic tool that takes multiple, detailed images of the inside of the body.
• Ultrasound. An imaging test that uses soundwaves to create pictures of the inside of the body.

Complications of EPI

When foods are not fully digested, the body cannot absorb the nutrients in those foods. EPI can also lead to unexplained weight loss, malnutrition, and complications such as anemia and osteoporosis.

• Malabsorption. This refers to difficulty digesting or absorbing nutrients from food.
• Malnutrition. This occurs due to the body’s inability to absorb nutrients.
• Anemia. A condition where your body’s red cell count is too low, so your body doesn’t receive enough oxygen.
• Osteoporosis. A disease that causes bones to become weak and brittle.

What to do with what you know

Having a good understanding of EPI can be helpful when talking to a healthcare provider—and a healthcare provider will be your best source of information. Managing EPI involves treating any underlying conditions, taking medications that replace the missing pancreatic enzymes, and addressing any complications caused by having EPI.