Crohn’s Disease

Author, Frank W. Jackson MD
Updated 2014

Crohn’s Disease is a chronic, recurrent inflammatory disease of the intestinal tract. The intestinal tract has four major parts: the esophagus, or food tube; the stomach, where food is churned and broken down; the long small bowel, where nutrients, calories, minerals, and vitamins are absorbed; and the colon, where water is absorbed, stool is stored and a good many health benefits occur. The two primary sites for Crohn’s disease are the last portion of the small bowel (the ileum) and the colon (Crohn’s colitis). The condition appears to start when the colon’s normal bacteria stick to the colon’s lining more readily. Normally, the colon easily fights this off as its immune defenses are so robust and strong. In Crohn’s Disease, however, this does not occur. Small nests of inflammation occur, persist and smolder. The inflammation becomes worse and spreads. The lining of the bowel can then become ulcerated and the bowel wall thickened. Eventually, the bowel may become narrowed or obstructed, at which time surgery would be needed.

What Causes Crohn’s Disease?

For the most part, Crohn’s Disease is a disorder of young people, even children. There is now evidence of a genetic link as Crohn’s frequently shows up in families and certain ethnic groups. For instance, the disease is more common in Jewish people and less so in African Americans. As noted, there is evidence that the normal healthy bacteria that grow in the lower gut may, in some manner, act to promote inflammation. The body’s immune system, which protects it against many different infections, is a factor.

So, a number of clear factors are necessary for Crohn’s Disease to occur.

  • There is a genetic link that predisposes some people.
  • The colon’s normal bacteria are necessary.
  • The colon’s own immune system fails to control the local infection.

There are still a number of unknowns about the cause of the disease; however, research is rapidly increasing our knowledge. Fortunately, a great deal is known and there are now a variety of effective treatments available.

Crohn’s Disease Symptoms

The symptoms of Crohn’s disease depend on where in the intestinal tract the disorder appears. When the ileum (ileitis) is involved, recurrent pain may be experienced in the right lower abdomen. At times, the pain mimics acute appendicitis. When the colon is the site, diarrhea (sometimes bloody) may occur, along with fever and weight loss. Crohn’s disease often affects the anal area where there may be a draining sinus tract called a fistula. When the disease is active, fatigue and lethargy appear. In children and adolescents, there may be difficulty gaining or maintaining weight. Nutrition and vitamin deficiencies often occur. So, the main symptoms of Crohn’s Disease may be:

  • Recurrent, lower abdominal discomfort
  • Failure to gain weight normally, especially in the young
  • Chronic fatigue and lethargy
  • Bowel urgency and/or diarrhea, sometimes bloody
  • Sores or drainage in the anal area


The diagnosis often begins with a physician’s suspicion that Crohn’s Disease may be present. The patient’s medical history and physical exam are always helpful. Certain blood and stool tests are necessary. X-rays of the small intestine and colon are usually required. In addition, a colonoscopy exam of the entire colon is often the best way of diagnosing the problem. A colonoscopy exam is where the colon is cleaned out and then visually inspected with a lighted endoscope. Biopsy specimens can be obtained. Colonoscopy is usually the definitive exam in making a diagnosis.

Course and Complications

The disorder often remains quiet and easily controlled for long periods of time. Most people with Crohn’s disease continue to pursue their goals in life, go to school, marry, raise a family, exercise and work with few limitations or inconveniences.

Some problems, outside the bowel, can occur. Arthritis, eye disorders, skin problems, and in rare instances, chronic liver conditions may develop. If the disease occurs around the anal canal, open painful sores called fissures can develop.  A fistula can also form. A fistula is a tiny channel that burrows from the rectum to the skin around the anus. Infrequently, fistulas can track into the urinary bladder, the vagina or even another part of the intestine. In addition, when inflammation persists in the ileum or colon, narrowing and partial obstruction may occur. Surgery is usually required to treat this problem. When Crohn’s disease has been present for many years, there is an increased risk of cancer.

A major problem that may occur very early in the disease is the loss of calcium in the bones. This occurs without any symptoms.  At this stage, it is called osteopenia. Later, when it progresses, it is called osteoporosis. Since Crohn’s Disease, for the most part, is a disease of young people, this bone loss can occur at a very early age. This is why most Crohn’s patients need to take extra calcium and vitamin D in their diet and with supplements. In addition, they should get a bone scan (densitometry) to detect early loss of bone. A simple x-ray will not detect early bone loss.


Effective medical and surgical treatment is available for Crohn’s disease. It is particularly important to maintain good nutrition with a balanced diet, get adequate exercise, consume adequate vitamins and minerals, especially calcium and vitamin D, and keep a positive, upbeat attitude. See Crohn’s Dietary Therapy for details. Five types of medications are available to treat this disease.

  • Cortisone or steroids (prednisone) – These powerful drugs can provide highly effective results. A large dose is often used initially to bring severe disease under quick control. The drug is then tapered to a low maintenance dose, perhaps taken just every other day. Hopefully, the drug may eventually be stopped altogether. Unfortunately, steroids promote calcium loss from bone. This is a major problem for Crohn’s patients. So, early detection and preventative therapy is imperative.
  • Anti-inflammation drugs – Sulfasalazine, (Azulfidine, Dipentum, Asacol, Rowasa, Pentasa and Lialda) belong to a group of drugs called the 5-aminosalicylates. These drugs are most useful in maintaining a remission, once the disease is brought under control. They are most effective when the disease is present in the colon and less so for Crohn’s in the small bowel.
  • Immune System Suppressors – These medications suppress the body’s immune system, which appears to be overly active and somehow aggravates the disease. The names of two of these commonly used medications are azathioprine (trade name: Imuran) and 6MP (trade name: Purinethol). These drugs are particularly useful for long-term maintenance. There are other potent immune-suppressing drugs that may be used in difficult cases.
  • Biologics – These are newer and highly effective compounds that block certain stages of the inflammation. Infliximab (trade name: Remicade) and adalimumab (trade name: Humira) are two such medications.
  • Antibiotics – Since there is frequently a bacterial infection along with Crohn’s disease, antibiotics are often used to treat this problem. Two that are commonly used are ciprofloxacin (trade name: Cipro) and metronidazole (trade name: Flagyl).

Dietary Therapy

Dietary therapy for Crohn’s patients is being increasingly recognized as a vital part of overall care. In a real sense, the patient must become an active partner in her or his care. Dietary therapy means that the patient or the caregiver of a patient understands the importance of the following in Crohn’s patients.

  • Protein – how much and what type
  • Carbohydrates – again, how much and what type
  • Fat
  • Vitamins – especially the importance of C, D and some of the B vitamins
  • Minerals – calcium, selenium, zinc
  • Fish oil
  • Herbs

A full outline of this information can be accessed on the Crohn’s Disease Dietary Therapy page.

Fiber, Prebiotics, and Probiotics

Fiber in plant food is now known to be especially healthy for everyone’s general health. For Crohn’s Disease patients, fiber can be recommended when the disease is inactive, and especially when there is no narrowing of the bowel, where plant fiber could induce blockage.

Soluble prebiotic fibers are a more recently discovered type of fiber, which has some real bowel benefits. Their use in Crohn’s patients is still not certain but since they are simply plant food, there are few side effects. The prebiotic fibers, inulin, and oligofructose are the names of the best-studied ones. They promote the growth of good colon bacteria which, in turn, make short chain fatty acids. These fatty acids may be a real benefit to Crohn’s patients as they seem to make bacteria less adherent to the bowel wall and are actually the fuel source for the bowels own cells.

Learn more about probiotics here.

A probiotic is a good bacteria or yeast taken by mouth that, hopefully, grows in the colon and produces good results. There is some scientific evidence that probiotics may help some Crohn’s patients. In particular, the use of probiotics and prebiotics together may be appropriate for some. Again, check with your physician.

Learn more about prebiotics here.

Stress and Surgery Surgery is commonly needed at some time during the course of Crohn’s disease. It may involve removing a portion of diseased bowel, or simply the draining of an abscess or fistula. In all cases, the guiding principle is to perform the least amount of surgery necessary to correct the problem. Surgery does not cure Crohn’s disease.


Most people with Crohn’s disease lead active lives with few restrictions. Although there is no known cure for the disorder, it can be managed with present treatments. There is increased emphasis on patients helping themselves by good dietary management, meaning adequate calories, vitamins, minerals and even prebiotic food fibers and probiotic bacteria. For a few patients, the course of the disease can be complicated, requiring extensive testing and therapy. Surgery sometimes is required. By working closely with your physician and managing your own emotional and dietary behavior, most patients will have a good long-term outcome.

Medical References

Inulin and oligofructose in chronic inflammatory bowel disease.

Clinical, microbiological, and immunological effects of fructo-oligosaccharide in patients with Crohn’s disease.