Chymotrypsin in Stool
Reviewed
Also called: Fecal chymotrypsin, Trypsin and chymotrypsin stool test
This test measures the amount of chymotrypsin, a pancreatic enzyme, in a stool sample. It helps check for exocrine pancreatic insufficiency (EPI), which can be caused by chronic pancreatitis or cystic fibrosis.
Specimen: Stool (fresh loose or liquid sample)
Why this test may be ordered
- To check for pancreatic insufficiency
- To help diagnose conditions such as pancreatitis and cystic fibrosis
- To help diagnose the cause of malnutrition
Preparation and collection
You may need to stop taking certain medicines, such as pancreatic enzymes, before this test. Tell your provider about everything you take, but do not stop any medicine unless your provider tells you to.
You will need to provide a fresh sample of loose or liquid stool. Your provider will give you a container or kit with instructions. In general, label the container with your name, date, and time; collect the sample using a clean, dry container or special paper/plastic wrap placed over the toilet; avoid mixing with urine, toilet paper, or toilet water; close the container tightly; wash your hands; and return the container according to instructions. Refrigerate the sample if you cannot return it right away. For diaper samples, special instructions using plastic wrap inside a clean diaper will be provided. In certain cases, a provider may use a swab to take a sample from the rectum.
There is no known risk to having a stool test.
Understanding results
Your results will show the amount of chymotrypsin in your stool. Your results may also include the amount of trypsin found. Discuss your results with your healthcare provider, who will interpret them based on your medical history and symptoms.
- Positive: Your stool sample shows a normal amount of chymotrypsin (and trypsin, if tested). Limitation: A positive result does not rule out all pancreatic disorders; further testing may still be needed if symptoms persist. Next step: If you have symptoms, your provider may still consider other tests or evaluations.
- Negative: The amount of chymotrypsin (and/or trypsin) in your stool sample is below normal. It may mean you have pancreatic insufficiency. Limitation: A negative result does not diagnose any specific disorder by itself. It only suggests a possible problem with pancreatic enzyme production. Next step: Your provider will need to order more tests, such as stool elastase, lipase blood test, or amylase blood test, to confirm the cause.
- A negative result does not diagnose any specific disorder by itself; it only suggests possible pancreatic insufficiency.
- The test may be affected by certain medications, such as pancreatic enzyme supplements.
- Results must be interpreted by a healthcare professional in the context of your overall health and symptoms.
- The test may not detect all cases of pancreatic insufficiency; additional tests may be needed.
What to do next
If you have a negative result, your provider will likely order additional tests to determine the cause, such as stool elastase, lipase blood test, or amylase blood test. If you have questions about your results, talk to your provider.
- What symptoms led to this test being ordered?
- Are there any medications I should stop before the test?
- How should I collect and store the stool sample?
- What do my results mean for my health?
- What follow-up tests might be needed?