Crohn's Disease

Overview

Crohn's disease is an inflammatory bowel disease (IBD). IBD is a general term for noninfectious conditions that involve chronic inflammation of the intestines, causing symptoms such as diarrhea, abdominal pain, fevers, bleeding and growth problems.

Ulcerative colitis is another kind of IBD, as is a more unusual form called microscopic colitis. Although Crohn's disease and ulcerative colitis are often difficult to distinguish from each other because they have many of the same symptoms, they affect the digestive tract differently.

Crohn's disease can involve any part of the digestive tract from the mouth to the anus, while ulcerative colitis is limited to the colon. In more than half of children with Crohn's disease, what's affected is the last part of the small intestine (the ileum) as well as the first part or much of the large intestine, colon and rectum. The inflammation also extends deeper into the lining of the intestinal wall in Crohn's disease than it does in ulcerative colitis.

About a third of children with Crohn's disease have external problems around their bottom, called perianal disease. Any child with a skin tag, fissure (tear) or abscess in the anal area should be evaluated for the disease.

About 25 percent of IBD cases begin in childhood, even in children under age 2. Diagnosis is often delayed because IBD is confused with other conditions, such as lactose intolerance, a stomach virus or school avoidance behavior.

Crohn's disease may relapse and then recur at various points in the patient's lifetime, with periods of symptom-free remission. There's no consistently accurate way to predict when remission will occur or when symptoms will return.

In some families, the condition is inherited. About 20 to 25 percent of people — and up to 40 percent of very young children — with Crohn's disease have a close relative with ulcerative colitis or Crohn's disease. The immune system's response to certain bacteria in the gut and the patient's genetic makeup are believed to be the primary causes.

In UCSF's IBD Program, a medical team of doctors, nurse practitioners, dietitians, social workers and other consultants — including pediatric experts in psychology and psychiatry, infectious diseases, rheumatology, dermatology, ophthalmology and surgery — work together to provide your child and family with optimal and state-of-the-art care. Please feel free to request information about our program at any time.

Signs & symptoms

Common symptoms of Crohn's disease include:

• Diarrhea
• Abdominal cramps and pain
• Fever
• Rectal bleeding
• Loss of appetite and weight loss
• Poor growth
• Joint pain
• Unusual skin rash

During periods of active symptoms, your child may also experience:

• Fatigue
• Joint pain
• Fissures: tears in the lining of the anus
• Fistulas: tunnels that connect the intestine to the bladder, vagina or skin
• Mouth or skin lesions

Because chronic diarrhea and inflammation can reduce the amount of nutrients absorbed from food, some children with Crohn's disease have stunted growth and delayed development.

Diagnosis

Your child's doctor will first do a physical examination and take a medical history. There's no single test for diagnosing Crohn's disease, so if the doctor suspects Crohn's, a series of tests is required to make a definitive diagnosis. Tests may include:

• Blood Tests — Blood tests check for anemia, which may be a sign of bleeding in the intestines. They can also detect a high white blood cell count or elevated levels of C-reactive protein, both markers of inflammation.
• Stool Sample — Shows whether there is bleeding, inflammation or infection in the intestines.
• Magnetic Resonance (MR) Enterography — Provides detailed images of the small bowel that can pinpoint areas of inflammation, bleeding and other problems. Before the test, your child drinks a contrast material (sometimes just milk is enough) to highlight the small bowel in the images. MR enterography is noninvasive and does not involve radiation or expose your child to any radiation.
• Colonoscopy — Allows the doctor to examine the entire length of the colon, using a long, flexible tube about as thick as your index finger with a tiny video camera and light on the end. Video images from the camera appear on a monitor. A colonoscopy is done under anesthesia in most children.
  As the colonoscope is pulled back out, the doctor gets even better views and can do a more careful examination. The colonoscope may also contain built-in instruments for taking tissue samples. Later, the doctor can further evaluate what's going on by examining these tiny biopsies of the lining (tissue) of the colon under a microscope.
• Upper Endoscopy (aka esophagogastroduodenoscopy or EGD) — Enables the doctor to examine the upper GI tract, from the mouth through the esophagus, the stomach and the first part of the intestine (as far as the duodenum and sometimes the first part of the jejunum). Like a colonoscopy, this procedure is usually done under anesthesia using a flexible tube with a tiny video camera and a light. Video images are shown on a monitor, and tissue samples can be taken for the doctor to examine later under a microscope.

• Capsule Endoscopy (or PillCam) — No anesthesia or sedative is needed for this test. The child swallows a capsule containing a light and a camera, which takes pictures of the entire intestinal tract as it travels from the stomach to the colon and eventually out of the body in the stool – typically a four- to five-hour process. (Sometimes a test capsule is given first, to make sure there's no intestinal stricture that might block its passage.) The disadvantage of capsule endoscopy is that no tissue is obtained for later study under a microscope.
  
  Note: The capsules are quite large, and smaller children can't always swallow them. In that case, the capsule is put into the intestine during an upper endoscopy.

Treatment

Although there's no cure for Crohn's disease, treatments are available.

Medications

Medications are used to suppress the inflammation associated with Crohn's disease. This helps the intestines heal, relieving symptoms and possibly preventing progression of disease and potential complications. Once symptoms are under control, medications may reduce the frequency of flare-ups (relapses) and prevent symptoms from recurring.

Medications for treating the disease include aminosalicylates, corticosteroids, immunomodulators and biologic therapy.

Nutrition as Therapy or Supplementation

Nutritional therapies can also help treat or at least support nutrition and growth of children with Crohn's disease. Special formulas can be used as a primary treatment for children in place of some medications. Some newer diets are being tested by our medical team. Or, your child's doctor may recommend nutritional supplements.

A small number of patients need to be fed by tube through the nose or intravenously from time to time. This can help those who temporarily need extra nutrition, who can't eat enough, whose intestines need to rest, or who can't absorb enough nutrition from food.

You can discuss all these options with your medical team, including a dietitian familiar with the treatment of Crohn's disease.

Surgery

Surgery may be suggested when medications are no longer effective. Typically, surgery removes the diseased part of the bowel and then joins the two healthy ends of the bowel together.

Another surgical option is an ileostomy. In this procedure, the surgeon creates a small opening in the abdomen — about the size of a quarter — and attaches it to the ileum (the end of the small intestine). Waste can then travel through the small intestine and exit the body through the opening and into a pouch. The patient empties the pouch as needed.

Although surgery can provide many symptom-free years, it's not considered a cure because the disease usually recurs. For this reason, doctors aim to avoid surgery or to remove as little as possible of the diseased part of the bowel.

Research

One focus of the UCSF IBD team is to find new and sometimes experimental ways to improve the management and long-term outcomes of our patients, often through multinational research projects. Patients may have the option of participating in research trials of new therapies for IBD.

We also track the progress of almost all our patients to help improve the treatment options and information we can offer future patients.