Several tests may be used by physicians to diagnose CD. If a physician suspects that IBD is the cause of symptoms, testing will help determine if it is CD or UC.
Barium enema. A barium enema (or lower gastrointestinal series) uses barium sulfate and air to outline the lining of the rectum and colon. The barium is given in an enema which is then 'held' inside the colon while X-rays are taken. Intestinal abnormalities may appear as dark silhouettes or patterns along the intestinal lining on the X-ray. A barium enema can be performed as an outpatient procedure, and usually takes about 45 minutes. The enema might be uncomfortable, but the X-rays are completely painless.
Upper GI Series An upper gastrointestinal (upper GI) series utilizes X-rays to find problems in the esophagus, stomach, and duodenum. Sometimes it may be used to examine the small intestine. When the barium is swallowed, it coats the inside of the upper digestive tract, making them show up clearly on an X-ray. Using a flouroscope, a radiologist will watch the barium move through the digestive system while noting any problems and taking X-rays. The entire test can take 1 to 2 hours and is not uncomfortable. Blockages, abnormal growths, ulcers, scar tissue and hernias can be found with an upper GI series.
Stool culture. A physician may want to rule out other causes for bloody diarrhea, such as a bacterial infection, with a stool culture. Stool must be collected into a specimen jar and brought to a laboratory for testing in a culture. If any bacteria grow in the culture, the scientists can test it to determine what it is and how best to treat it.
Blood tests. A blood test may be used to determine a white blood cell count or if anemia is present. Repeated bouts of bloody diarrhea may cause some people to become anemic. A white blood cell count gives physicians an indication that inflammation is taking place somewhere inside the body. An elevated white blood cell count does not tell physicians where in the body the inflammation is located, and anemia could be from one of several causes. However, both tests provide clues for physicians to use when making a diagnosis.
Fecal occult blood test. Even though the blood in the stool may be visible to the naked eye, a physician may decide to include a fecal occult blood test. This test can detect bleeding from almost anywhere in the digestive tract. The stool collection may be done at home without any discomfort and returned to the physician or laboratory for testing.
Sigmoidoscopy. A sigmoidoscopy is a way for a doctor to examine the last one third of the large intestine, which includes the rectum and sigmoid colon. To clear out the colon, patients may be asked to use laxatives or an enema, or have only liquid foods on the day of the test. A flexible viewing tube with a lens and light source on the end, called a sigmoidoscope, is used. A biopsy may be taken during the procedure, which will be tested to help the physician determine the cause of any inflammation. This procedure may be done either in a hospital setting or in a doctor’s office and takes about 15-30 minutes. A sigmoidoscopy is uncomfortable, but it is not painful.
Colonoscopy. A colonoscopy is used to examine the inside of the colon beyond the areas a sigmoidoscopy can reach. This test uses a colonoscope, which is a flexible tube with lenses, a tiny TV camera and a light at the end. The intestine must be empty for the procedure, and physicians may prescribe one of several ways to prep the bowel including GoLytely, Phospho-Soda and/or a liquid diet. Biopsies may be taken during the test, which is done in a hospital outpatient setting and may take up to 1 ½ hours. During the procedure patients are normally sedated or given “twilight sleep” so that they do not feel any pain or even remember the test.
Other tests may be used by physicians as needed to diagnose CD, or rule out other potential diagnoses.
