In order to diagnose Crohn's disease, a provider will take a medical history and do a physical examination. Blood and stool samples may be analyzed to look for signs of anemia, infection, inflammation, and other potential digestive diseases. One or more imaging tests may then be ordered.
Upper GI Endoscopy
An endoscope is a thin, flexible tube with a tiny camera at the end that can be passed through the mouth to allow the provider to look for evidence of Crohn's disease in the inner lining of the upper GI tract. Biopsies can also be taken during this procedure to sample tissue for testing and diagnosis.
Colonoscopy is a procedure in which a provider passes a thin, flexible tube with a tiny camera at the end through the anus to look inside the rectum and the entire colon for visual or microscopic evidence of Crohn's disease. Tissue samples can be taken during a colonoscopy for microscopic evaluation.
A flexible sigmoidoscopy is similar to a colonoscopy, but it only provides a view of the rectum and lower part of the colon, called the sigmoid colon. Tissue samples can also be taken during a flexible sigmoidoscopy.
In capsule endoscopy, the patient swallows a capsule containing a tiny camera that collects images to allow the provider to see inside the digestive tract, specifically targeting the majority of the small intestine, which cannot be seen with upper endoscopy or colonoscopy. As the capsule passes through the digestive tract, the camera records and transmits images to a small receiver device worn by the patient, or captures the images within the capsule, which are later downloaded for viewing. The camera capsule leaves the body during a bowel movement and can be safely flushed down the toilet or collected for image retrieval.
CT Enterography and MR Enterography
Computed tomography, or CT, enterography uses a combination of x-rays and computer technology to evaluate the small intestine. Magnetic resonance, or MR, enterography uses a powerful magnet and radio waves to create images of the small intestine. Both of these imaging tests allow the provider to see the lumen and mucosal surface of the small intestine to look for evidence of inflammation, scarring, stenosis, or other changes related to Crohn's disease.
Lower GI Series
Lower gastrointestinal, or GI, series is also called barium enema. Barium is passed through the anus to coat the rectum and colon, and a series of x-rays are taken.
Upper GI Series
Upper GI series is also called barium swallow. The patient swallows barium to coat the inside of the esophagus, stomach, and small intestine, and a series of x-rays are taken.
A CT scan uses a combination of x-rays and computer technology to create images of internal organs. A special dye, called contrast medium, may be injected to make structures inside the body easier to see. CT scans can assist in diagnosing complications of Crohn's disease.