The exact cause of Crohn's disease is unknown. It occurs when your body's immune system mistakenly attacks and destroys healthy body tissue (autoimmune disorder).
When parts of the digestive tract remain swollen or inflamed, the walls of the intestines become thickened.
Factors that may play a role in Crohn's disease include:
Your genes and family history (People of Jewish descent are at higher risk.)
Tendency of your body to over-react to normal bacteria in the intestines
Crohn's disease may occur at any age. It most often occurs in people between ages 15 - 35.
Symptoms depend on what part of the digestive tract is involved. Symptoms range from mild to severe, and can come and go with periods of flare-ups.
The main symptoms of Crohn's disease are:
Crampy pain in the abdomen (belly area)
Loss of appetite
Feeling that you need to pass stools, even though your bowels are already empty. It may involve straining, pain, and cramping.
Watery diarrhea, which may be bloody
Other symptoms may include:
Sores or swelling in the eyes
Draining of pus, mucus, or stools from around the rectum or anus (caused by something called a fistula)
Joint pain and swelling
Rectal bleeding and bloody stools
Tender, red bumps (nodules) under the skin which may turn into skin ulcers
Exams and Tests
A physical exam may show a mass or tenderness in the abdomen, skin rash, swollen joints, or mouth ulcers.
Tests to diagnose Crohn's disease include:
Barium enema or upper GI series
Colonoscopy or sigmoidoscopy
CT scan of the abdomen
MRI of the abdomen
A stool culture may be done to rule out other possible causes of the symptoms.
This disease may also alter the results of the following tests:
Low albumin levels
High sed rate
Low blood count (hemoglobin and hematocrit)
Abnormal liver blood tests
High white blood cell count
DIET AND NUTRITION
You should eat a well-balanced, healthy diet. Include enough calories, protein, and nutrients from a variety of food groups.
No specific diet has been shown to make Crohn's symptoms better or worse. Types of food problems may vary from person to person.
Some foods can make diarrhea and gas worse. To help ease symptoms, try:
Eating small amounts of food throughout the day.
Drinking lots of water (drink small amounts often throughout the day).
Avoiding high-fiber foods (bran, beans, nuts, seeds, and popcorn).
Avoiding fatty, greasy or fried foods and sauces (butter, margarine, and heavy cream).
Limiting dairy products if you have problems digesting dairy fats. Try low-lactose cheeses, such as Swiss and cheddar, and an enzyme product, such as Lactaid, to help break down lactose.
Avoiding foods that you know cause gas, such as beans.
Ask your doctor about extra vitamins and minerals you may need, such as:
Iron supplements (if you are anemic)
Calcium and vitamin D supplements to help keep your bones strong
Vitamin B12 to prevent anemia
You may feel worried, embarrassed, or even sad and depressed about having a bowel disease. Other stressful events in your life, such as moving, a job loss, or the loss of a loved one can worsen digestive problems.
Ask your doctor or nurse for tips on how to manage your stress.
You can take medication to treat very bad diarrhea. Loperamide (Imodium) can be bought without a prescription. Always talk to your doctor or nurse before using these drugs.
Other medicines to help with symptoms include:
Fiber supplements may help your symptoms. You can buy psyllium powder (Metamucil) or methylcellulose (Citrucel). Ask your doctor before taking these products or laxatives.
Acetaminophen (Tylenol) for mild pain. Avoid drugs such as aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn) which can make your symptoms worse.
Your doctor may also prescribe medicines to help control Crohn's disease:
Aminosalicylates (5-ASAs) - medicines that help control mild to moderate symptoms. Some forms of the drug are taken by mouth; others must be given rectally.
Corticosteroids, such as prednisone - treat moderate to severe Crohn's disease. They may be taken by mouth or inserted into the rectum.
Medicines that quiet the immune system's reaction.
Antibiotics - treat abscesses or fistulas.
Biologic therapy- used for severe Crohn's disease that does not respond to any other types of medication.
Some people with Crohn's disease may need surgery to remove a damaged or diseased part of the intestine. In some cases, the entire large intestine is removed, with or without the rectum.
People who have Crohn's disease that does not respond to medications may need surgery to treat problems such as:
Failure to grow (in children)
Fistulas (abnormal connections between the intestines and another area of the body)
Narrowing of the intestine
Surgeries that may be done include:
Removal of part of the large bowel or small bowel (link to surgery)
Removal of the large intestine to the rectum.
Removal of the large intestine and most of rectum
The Crohn's and Colitis Foundation of American offers support groups throughout the United States.
There is no cure for Crohn's disease. The condition is marked by periods of improvement followed by flare-ups of symptoms. Although Crohn's disease cannot be cured even with surgery, treatment can offer significant help to most patients.
You have a higher risk for small bowel and colon cancer if you have Crohn's disease. At some point, your doctor may recommend tests to screen for colon cancer.
Those with more severe Crohn's disease may have these problems:
Abscess or infection in the intestines
Anemia, a lack of red blood cells
Fistulas in the bladder, skin, or vagina
Slow growth and sexual development in children
Swelling of the joints
Lack of important nutrients, such as vitamin B12 and iron
Problems with maintaining a healthy weight
When to Contact a Medical Professional
Call your health care provider if:
You have very bad abdominal pain
You cannot control your diarrhea with diet changes and drugs
You have lost weight, or a child is not gaining weight
You have rectal bleeding, drainage, or sores
You have a fever that lasts for more than 2 or 3 days, or a fever higher than 100.4°F without an illness
You have nausea and vomiting that lasts for more than a day
You have skin sores that do not heal
You have joint pain that prevents you from doing your everyday activities
You have side effects from medicines you are taking for your condition
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Lichtenstein GR, Hanauer SB, Sandborn WJ; Practice Parameters Committee of American College of Gastroenterology. Management of Crohn's disease in adults. Am J Gastroenterol. 2009;104(2):465-483.
Fry RD, Mahmoud N, Maron DJ, Ross HM, Rombeau J. Colon and rectum. In: Townsend CM, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 50.
Sands BE, Siegel CA. Crohn's disease. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 111.
George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.