Crohn's disease is a disease where parts of the digestive tract become inflamed.

• It most often involves the lower end of the small intestine and the beginning of the large intestine.
• It may also occur in any part of the digestive system from the mouth to the end of the rectum (anus).
• Crohn disease is a form of inflammatory bowel disease (IBD).
• Ulcerative colitis is a related condition.

The exact cause of Crohn 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 disease include:

• Your genes and family history. (People who are white or of Eastern European Jewish descent are at a higher risk.)
• Environmental factors.
• Tendency of your body to over-react to normal bacteria in the intestines.
• Smoking.

Crohn disease may occur at any age. It mostly occurs in people between ages 15 and 35.

Symptoms depend on the part of the digestive tract involved. Symptoms range from mild to severe, and can come and go, with periods of flare-ups.

The main symptoms of Crohn disease are:

• Crampy pain in the abdomen (belly area).
• Fever.
• Fatigue.
• Loss of appetite and weight loss.
• 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:

• Constipation
• 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
• Mouth ulcers
• Rectal bleeding and bloody stools
• Swollen gums
• Tender, red bumps (nodules) under the skin, which may turn into skin ulcers

A physical exam may show a mass or tenderness in the abdomen, skin rash, swollen joints, or mouth ulcers.

Tests to diagnose Crohn disease include:

• Barium enema or upper GI (gastrointestinal) series
• Colonoscopy or sigmoidoscopy
• CT scan of the abdomen
• Capsule endoscopy
• MRI of the abdomen
• Enteroscopy

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 level
• High sed rate
• Fecal fat
• Low blood count (hemoglobin and hematocrit)
• Abnormal liver blood tests
• High white blood cell count
• Elevated fecal calprotectin level in stool

Tips for managing Crohn disease at home

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 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 and vegetables in the cabbage family, such as broccoli.

Ask your health care provider 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

If you have an ileostomy, you will need to learn:

• Diet changes
• How to change your pouch
• How to care for your stoma

STRESS
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 provider for tips on how to manage your stress.

MEDICINES
You can take medicine to treat very bad diarrhea. Loperamide (Imodium) can be bought without a prescription. Always talk to your provider before using these drugs.

Other medicines to help with symptoms include:

• Fiber supplements, such as psyllium powder (Metamucil) or methylcellulose (Citrucel). Ask your provider 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 provider may also prescribe medicines to help control Crohn disease:

• Aminosalicylates (5-ASAs), medicines that help control mild to moderate symptoms. Some forms of the drug are taken by mouth, and others must be given rectally.
• Corticosteroids, such as prednisone, treat moderate to severe Crohn disease. They may be taken by mouth or inserted into the rectum.
• Medicines that quiet the immune system's reaction.
• Antibiotics to treat abscesses or fistulas.
• Immunosuppressive drugs such as Imuran, 6-MP, and others to avoid long-term use of corticosteroids.
• Biologic therapy may be used for severe Crohn disease that does not respond to any other types of medicines.

SURGERY
Some people with Crohn 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 disease that does not respond to medicines may need surgery to treat problems such as:

• Bleeding
• Failure to grow (in children)
• Fistulas (abnormal connections between the intestines and another area of the body)
• Infections
• Narrowing of the intestine

Surgeries that may be done include:

• Ileostomy
• Removal of part of the large bowel or small bowel
• Removal of the large intestine to the rectum
• Removal of the large intestine and most of rectum

The Crohn's and Colitis Foundation of America offers support groups all over the United States -- www.crohnscolitisfoundation.org

There is no cure for Crohn disease. The condition is marked by periods of improvement followed by flare-ups of symptoms. Crohn disease cannot be cured, even with surgery. But the surgical treatment can offer major help.

You have more risk for small bowel and colon cancer if you have Crohn disease. Your provider may suggest tests to screen for colon cancer.

Those with more severe Crohn disease may have these problems:

• Abscess or infection in the intestines
• Anemia, a lack of red blood cells
• Bowel blockage
• 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
• Swelling of the bile ducts (primary sclerosing cholangitis)

Call your provider if you:

• Have very bad abdominal pain
• Cannot control your diarrhea with diet changes and drugs
• Have lost weight, or a child is not gaining weight
• Have rectal bleeding, drainage, or sores
• Have a fever that lasts for more than 2 or 3 days, or a fever higher than 100.4°F (38°C) without an illness
• Have nausea and vomiting that lasts for more than a day
• Have skin sores that do not heal
• Have joint pain that prevents you from doing your everyday activities
• Have side effects from medicines you are taking for your condition

Crohn disease; Inflammatory bowel disease - Crohn disease; Regional enteritis; Ileitis; Granulomatous ileocolitis; IBD - Crohn disease