Diagnosing Chrohn's disease

Your child’s diagnosis of Crohn’s disease or ulcerative colitis will likely occur following a few tests. In addition to a thorough medical history and physical examination, children may undergo a combination of blood tests, barium x-rays, magnetic resonance imaging (MRI), and endoscopy of the upper and lower GI tract. In general, physicians will begin by prescribing the least invasive tests, progressing to more invasive testing until a diagnosis is obtained. This is especially true in pediatric patients.

• Blood tests are done to check for a low red cell count (anemia) or high white cell count (inflammation). Other blood tests may be performed to look for evidence of inflammation in the intestine and elsewhere. More recently, various antibody tests have been discovered that can show the altered GI immune process in some people with IBD.
• Barium x-rays and MRI include the upper GI and small bowel series, which helps to visualize areas of the intestines that are out of reach of endoscopies (see next bullet). Sometimes, a video capsule may be used to inspect the bowel wall as well. (The lower GI series, or barium enema, has been replaced by colonoscopy.) During the small bowel series, your child swallows a chalky liquid containing barium or a similar material that coats the upper intestinal tract so it will show up on an x-ray or MRI. Areas of swelling, narrowing, or other signs of intestinal inflammation can be identified with these imaging techniques. X-rays, MRIs, and other imaging tests will be used wisely to limit your child’s lifetime exposure to radiation.
• Endoscopy is a test that involves inserting a lighted viewing tube through either the mouth into the upper intestine (upper endoscopy) or through the anus into the colon (colonoscopy). The physician performing the exam can also remove tiny pieces of tissue (biopsies) from the intestines, which are later examined for microscopic signs of the diseases. During the endoscopy, your child’s doctor may also insert a video capsule, which takes pictures of the inside of the small intestine. These pictures can show areas of soreness, ulceration, or bleeding that may not be detectable by other methods. Generally, these tests are performed on children who are sedated. A new form of endoscopy, called the pill endoscopy, does not involve anesthesia. Instead, a patient swallows a small pill-shaped camera, which takes about 50,000 pictures as it travels through the intestines; the images are captured on a device stored in a belt that the child wears for a day. The camera pill is excreted in the child’s stool.

Without appropriate testing, IBD can be difficult to diagnose, because Crohn’s disease and ulcerative colitis may look like other conditions. One example of this is irritable bowel syndrome, or IBS. IBS shares many symptoms of IBD, including abdominal pain and diarrhea. However, IBS is a functional bowel disorder, meaning the muscles of the intestines react improperly, either moving the bowel contents too quickly or too slowly. IBS does not involve inflammation, however. Because there are no physical signs of IBS, it is usually diagnosed after ruling out other conditions, including Crohn’s and colitis.

In some individuals, it is difficult to determine whether their IBD is Crohn’s disease or ulcerative colitis—even after extensive testing. Very rarely, people are given the diagnosis of “indeterminate colitis.” Such uncertainty is more common in the youngest patients—those under five years old at the time of diagnosis.