Trypsin and chymotrypsin are substances released from the pancreas during normal digestion. When the pancreas does not produce enough trypsin and chymotrypsin, smaller-than-normal amounts can be seen in a stool sample.
This article discusses the test to look for trypsin and chymotrypsin in stool.
Stool - trypsin and chymotrypsin
How the test is performed:
There are many ways to collect the samples. Your health care provider will instruct you on how to collect the stool.
You can catch the stool on plastic wrap that is loosely placed over the toilet bowl and held in place by the toilet seat. Then put the sample in a clean container. One type of test kit supplies a special tissue that you use to collect the sample, then put the sample in a clean container.
Infants and young children:
For children wearing diapers, you can line the diaper with plastic wrap. The plastic wrap should be positioned to prevent the mixing of urine and stool.
A drop of emulsified stool is placed on a thin layer of gelatin. If trypsin or chymotrypsin are present, the gelatin will be digested, which will produce a clearing of the gelatin.
How to prepare for the test:
Your health care provider will provide you with the necessary supplies to collect the stool.
Why the test is performed:
These tests are simple but indirect ways of finding out if you have a decrease in pancreas function.
These tests are most often done in young children suspected of having cystic fibrosis . Note: This test is used as a screening tool for cystic fibrosis but it does not diagnose cystic fibrosis. Other testing is needed to confirm a diagnosis of cystic fibrosis.
A normal result is normal concentration of trypsin or chymotrypsin in the stool.
What abnormal results mean:
An abnormal result means your trypsin or chymotrypsin levels in the stool are below the normal range. This may mean that the pancreas is not working properly. Other tests may be done to confirm that there is a problem with the pancreas.
Forsmark C. Chronic pancreatitis. In: Feldman M, Friedman L, Brandt L, eds. Sleisinger and Fordtran’s Gastrointestinal and Liver Disease. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2006:chap 57.