What Is Secretin?
When partially digested food from your stomach arrives in your small intestine, your small intestine produces a hormone called secretin. Secretin makes your pancreas release a fluid that contains inactive digestive enzymes and bicarbonates. This fluid moves from your pancreas into the upper portion of your small intestine, your duodenum. The fluids neutralize your stomach acids to activate your pancreatic enzymes. These enzymes help your body break food down and absorb its nutrients.
Some pancreatic diseases such as cystic fibrosis, chronic pancreatitis, and pancreatic cancer make it harder for your pancreas to respond to secretin. When this happens, your pancreas can’t deliver enough digestive enzymes to your small intestine to help the digestion process. This is called pancreatic insufficiency.
Cystic fibrosis (CF), pancreatitis, and pancreatic cancer can cause pancreatic insufficiency.
CF is a genetic disease. If you have CF, you may develop mucus in your lungs and pancreas. Mucus can obstruct the ducts leading out of the pancreas and make it hard for your body to deliver pancreatic fluid to your duodenum. Children who have pancreatic insufficiency often have CF. They may also be malnourished.
Pancreatitis is an inflammation of your pancreas. If you have pancreatitis, enzymes that are normally inactive until they reach your small intestine become activated earlier. They start digesting while still in your pancreas. The symptoms of pancreatitis include abdominal pain, nausea, and vomiting.
If you have chronic pancreatitis or pancreatic cancer, you may have damage to the cells that produce pancreatic enzymes. You may also have damage to the duct that delivers these enzymes to your small intestine. This will lead to insufficient pancreatic enzymes in your small intestine to properly digest food. In adults, pancreatic insufficiency is most commonly associated with pancreatitis. However, less often, damage can also be caused by pancreatic cancer.
Your doctor will need to perform several tests to diagnose pancreatic diseases.
The secretin stimulation test can show them how your pancreas functions in response to secretin. It can help your doctor learn how your pancreas works during digestion. It’s also called the pancreatic function test.
This test is invasive and conducted only when other evidence suggests you have pancreatic insufficiency.
You’ll need to fast for 12 hours before your secretin stimulation test. Your doctor will ask you to avoid eating any food or drinking any liquids, including water. Undergoing this test on an empty stomach reduces the risk of complications.
Your doctor will test how your pancreas responds to secretin by inserting a tube through your nose, into your esophagus, and through your stomach until it reaches your duodenum. Your doctor will then inject secretin intravenously into your body. If your body releases pancreatic fluid in response to the secretin, that fluid will be removed through the tube sitting in your duodenum within an hour or two.
You may experience irritation in your nose and a gagging sensation when your doctor inserts the tube. There’s also a small risk that the tube could be inserted into your trachea and go into your lungs, instead of your esophagus. However, your doctor will make sure the tube is placed correctly before continuing with the test.
If your test results are abnormal, this means you have some degree of pancreatic insufficiency. Abnormal results may mean you have CF, pancreatitis, or pancreatic cancer. However, abnormal results from this test alone are not enough for your doctor to diagnose these diseases. They’ll need to perform other tests to learn what’s causing your pancreatic insufficiency.
It’s not easy to diagnose pancreatitis or pancreatic cancer. For one thing, many symptoms of pancreatitis are similar to those of pancreatic cancer. Many of the symptoms aren’t specific to diseases of the pancreas either. They can point to a number of different diseases. There are also different types of pancreatitis. You may have acute or chronic pancreatitis. Each type requires different tests before your doctor can make a diagnosis.
If your doctor suspects you have pancreatitis, they’ll probably conduct blood work. You may also undergo stool testing and other imaging tests.
If you have chronic pancreatitis, you have a higher-than-normal risk of contracting pancreatic cancer. If your doctor believes you might have pancreatic cancer, they’ll order other tests, such as a biopsy of your pancreas.
Pancreatic disease often manifests with symptoms of abdominal pain, nausea, and vomiting. Your doctor can use several tests to diagnose the cause of your symptoms. For example, the secretin stimulation test allows them to test how your pancreas functions in response to secretin. This is an important hormone in the digestive process.
If your secretin stimulation test results are abnormal, you may have a pancreatic disease such as pancreatitis, pancreatic cancer, or cystic fibrosis. Speak with your doctor to learn more about your diagnosis, treatment, and long-term outlook.