A
of a sample of tissue from the lining of the
intestine, collected during sigmoidoscopy or colonoscopy, can be used to
confirm the diagnosis of Crohn's disease. A biopsy also may be done to find out
whether a tumor is present. Multiple biopsies for cancer screening are often
done in people who have had Crohn's disease of the colon or rectum for 8 years or more. Bowel biopsies are painless (other than the potential discomfort
of the scope procedure) and remove only a tiny piece of tissue.
A
stool analysis is often done, depending on symptoms,
to look for blood, signs of bacterial infection, malabsorption, parasites, or
the presence of white blood cells. This test can be used to distinguish Crohn's
disease from
(IBS), which is a less
serious condition that sometimes has similar symptoms.
Other exams and tests that may also be used to
evaluate Crohn's disease include:
- Video capsule endoscopy (VCE), in which you swallow a
tiny camera that records its trip through your digestive tract by sending
images to a recording device that you wear on a belt. Your doctor later
examines the images by downloading them from the recording device. The camera
passes out of your body in stool within 10 to 48 hours. VCE is particularly
useful in examining the small intestine, which is difficult to see with other
endoscopic tests.
- Small bowel enteroscopy, which uses a longer, lighted flexible
tube with a tiny camera that sends pictures of the small intestine to a video
screen. This helps the doctor look at the small intestine. The doctor can also
take small samples () of the tissue.
- Blood tests to find , which can sometimes help the doctor tell if you have Crohn's disease or ulcerative colitis. These tests include anti-neutrophil cytoplasmic antibody with perinuclear staining (pANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and outer membrane porin C (Omp C).
Early Detection
No screening test exists for Crohn's disease at
this time. But if you have had Crohn's disease affecting the colon or rectum
for 8 years or longer, discuss with your doctor whether you need
screening for colon cancer. Screening usually involves taking multiple-tissue
biopsies during routine colonoscopy.