Stool Tests for IBD: What You Should Know

B.S. Dietetics, Dietitian, Health Professional

Stool testing has long been used in conjunction with other techniques to diagnose, change treatments, or assess the long-term health of a patient. While not a diagnostic tool on their own, stool tests can add to the big picture for someone living with inflammatory bowel disease (IBD).

Can a stool test diagnose IBD?

Unfortunately, there are no stool tests that serve as a gold standard for diagnosing IBD. In most instances, physicians will need to biopsy the gastrointestinal (GI) tract to ensure that you are dealing with IBD and which type.

What do doctors look for in stool-test results?

Stool testing can monitor inflammation through measurements of fecal calprotectin. Blood in the stool may indicate an active ulceration within the GI tract. Cultures of stool may also be done if the physician thinks that there may be a bacteria or protozoa present. Stool samples may also be used to rule out other infections that can mimic IBD like C. difficile, E. coli, Campylobacter, Yersinia, Salmonella, Shigella, and others.

Is there special prep for a stool test?

In many cases, there are no preps needed for a stool test. However, if your physician is also looking for blood in the stool, they may ask you to refrain from eating certain fruits and vegetables, like broccoli and turnips, or red meat, vitamin C supplements, and pain relievers, such as aspirin and ibuprofen.

What happens during the test?

Often, you are sent home to collect a stool sample that you bring back to the hospital lab or the physician’s lab. For children still in diapers, it can be as simple as saving the diaper contents.  For kids, sometimes the gastroenterologist can get enough of a stool sample to test through the basic rectal exam (which is usually part of the overall check-up anyway and involves inserting the physician’s finger into the rectum to look for nodules or abnormalities). My daughter had one done at 3 years old, and it didn’t even faze her.

While the test sounds gross and unappealing, please don’t let it dissuade you from following your physician’s orders. These tests can be essential in monitoring IBD and helping to rule out other diseases (including cancers), and they are so simple to have done. They even have home monitoring kits for people without these other risk factors.

If you are still concerned or squeamish, talk with your physician. They will be able to reassure you about the test and how to get through it as easily as possible.

See more helpful articles:

6 Ways to Prepare for an Ulcerative Colitis Flare

Doctor Q&A: How to Manage Ulcerative Colitis

Different Types of Colitis

Sleep and Diet Changes May Help IBD Patients