Crohn’s Disease: Cause Unknown

~ by Jo Jordan

Crohn’s disease (CD) and ulcerative colitis (UC) are similar illnesses;
they belong to a group of disorders known as inflammatory bowel disease (IBD). Both illnesses inflame the lining of the digestive or gastrointestinal (GI) tract.

Crohn’s disease, however, can affect any area in the GI tract – from the mouth to the anus – often spreading deep into the layers of affected tissues, causing swelling and breaks in intestinal lining. Crohn’s disease inflammation is concentrated in some areas more than others, involving bowel layers that are deeper than the superficial inner layers.

With Crohn’s disease, normal healthy bowel tissue can be found between diseased, deeply ulcerated sections, while ulcerative colitis inflammation tends to affect all of the lining in the effected segment of the intestine uniformly.

Also referred to as granulomatous enteritis, granulomatous colitis, regional enteritis, and regional ileitis, etc. (see Types of Crohn’s disease, below), Crohn’s disease is chronic, commonly affecting the lower part of the small intestine (the ileum). ulcerative colitis, however, normally involves only the superficial layers of the bowel, affecting only the colon (the innermost lining of the large intestine) and rectum.

While there is presently no cure for Crohn’s disease, treatment can substantially reduce symptoms, and sometimes bring about long-term remission.

Effects of Crohn’s Disease on the Intestines

Crohn’s disease begins with small, scattered, shallow, erosions on the inner surface of the bowel. Eventually, the erosions – as they get deeper and larger – become ulcers, and begin to scar and stiffen the bowel.

Over time, the bowel gets narrower, and often becomes obstructed. The flow of contents through the intestine stops. Ulcers can puncture the bowel wall, allowing bowel bacteria to spread, infecting nearby organs and surrounding abdominal cavity.

Types of Crohn’s Disease1

Crohn’s colitis is inflammation confined to the colon.

Crohn’s enteritis refers to inflammation confined to the small intestine (the jejunum and the ileum). Involvement of the ileum alone is referred to as Crohn’s ileitis.

Crohn’s terminal ileitis is inflammation affecting only the very end of the small intestine (terminal ileum), the part of the small intestine closest to the colon.

Crohn’s entero-colitis and ileo-colitis – the most common types – is inflammation involving both the small intestine and colon.

Who Gets Crohn’s Disease? Causes and Risk Factors

While they may frustrate symptoms, diet and stress do not cause Crohn’s Disease. The exact cause is unknown, but the following factors are thought to contribute to the onset of Crohn’s disease:

Heredity: Crohn’s disease tends to run in families – approximately twenty percent of people with Crohn’s disease have a blood relative with some form of inflammatory bowel disease (IBD).2

Immune system vulnerability: A genetic susceptibility may trigger an abnormal response to the bacterium in some people, leading to Crohn’s disease onset. Viruses may also be responsible for Crohn’s disease.3

The following Crohn’s Disease risk factors have been documented:

Age: Crohn’s disease occurs in all age groups, but is more often diagnosed in people between twenty and thirty.

Ethnicity: Crohn’s disease occurs in all groups, but whites are at the highest risk – people of Jewish heritage of European descent are four to five times as likely as others to have Crohn’s disease.4

Gender: Crohn’s disease affects men and women almost equally, but Crohn’s disease is marginally more frequent in women.

Locale: Crohn’s disease occurs more often in people living in cities, industrial nations, and northern climates.

Smoking: Crohn’s disease is far more likely to develop in smokers.

Isotretinoin (Accutane) use: This drug – used to treat scarring cystic acne – has been linked to the development of IBD.5

Symptoms and Complications of Crohn’s Disease

Common symptoms include abdominal pain (often in the lower right area) and cramping, diarrhea, and weight loss. Poor appetite, fever, night sweats, rectal pain, and rectal bleeding – which may be persistent and result in anemia – are less commonly experienced.

Other symptoms and complications include arthritis; bile duct and liver inflammation; bright red or dark blood in stool; eye problems; fatigue; gallstones; kidney stones; intestinal bleeding, blockage, distention (expansion), and perforation (tearing); joint and spine pain; malnutrition; skin problems; ulcers; fissures (long ulcers); fistula or abscess; and increased risk for colon cancer.

Crohn’s disease inflammation may tunnel through the bowel wall into nearby organs creating an abnormal connection known as a fistula. This can result in an abscess – a swollen, pus-filled sore. The fistula may also tunnel out through the skin, which commonly happens in the area around the anus.

Children with Crohn’s disease may experience delayed growth and/or stunted sexual development.

Symptoms may develop slowly, over time, or come on suddenly. The range, severity of symptoms, and course of Crohn’s disease varies considerably. Some people experience long periods without any symptoms, while others have recurrent episodes. Crohn’s disease symptoms are dependent on the location, the extent, and the severity of the inflammation.

As many as one third of Crohn’s disease patients develop one or more of the following conditions involving the anal area:6

  • Swelling of anal sphincter tissue (the muscle at the end of the colon that controls defecation);
  • The development of ulcers within the anal sphincter, which may cause bleeding and pain during bowel movements;
  • The development of anal fistulae between the anus or rectum and the skin surrounding the anus, which may result in mucous and pus draining from the openings of fistulae; and/or
  • The development of abscesses around the anus and rectum, which can cause fever and anal pain and tenderness.

Diagnosing Crohn’s Disease

Laboratory tests

Along with a complete physical exam, a series of tests may be necessary to make an accurate Crohn’s disease diagnosis. The most commonly used diagnostic techniques for Crohn’s disease include,

A complete blood count (CBC)

To check for anemia, sometimes a sign of intestinal bleeding.

To uncover a high white blood cell count, a sign of the presence inflammation.

To uncover sedimentation rates (a measure of the separation of red blood cell matter over a given period of time). Depending on the outcome rate, infection and/or inflammation could be indicated.

Other blood tests may reveal low red blood cell counts (anemia), low blood proteins, and low body minerals, an effect of chronic diarrhea.

Anti-body tests

Various tests screen for the presence of certain antibodies. Results can assist in pinpointing which type of IBD is indicated.

Stool studies

Stool samples can indicate the presence of intestinal bleeding or infection.


Endoscopic tests for specific sections of the GI tract are used to do a visual exam and Crohn’s disease diagnosis. All use a thin, flexible tube with a lighted camera inside the tip, which enables health care providers to examine the GI tract lining.

Sigmoidoscopy — Examines the lining of the sigmoid colon (the lower third of the large intestine). This test may overlook inflammation and bleeding higher up in the colon and/or small intestine.

Colonoscopy — Examines the lining of the entire large intestine (colon), and can sometimes peek into the end of the small intestine. A biopsy – the taking of a tissue sample from the intestinal lining to be used for further examination – may also be performed during a colonoscopy to detect clusters of granulomas. Inflammatory cells, granulomas can confirm a Crohn’s disease diagnosis because they aren’t present with ulcerative colitis.

More accurate than barium X-rays in detecting small ulcers or areas of inflammation of the colon and terminal ileum, a colonoscopy is also a better tool for assessing the degree of inflammation. Barium can also be administered via the rectum. Referred to as a
barium enema
, this procedure is used to collect X-ray images of the colon and the terminal ileum, revealing ulcerations, narrowing, and bowel fistulae.

Video capsule endoscopy — Computerized video cameras in vitamin-sized capsules are swallowed to gather images of sections of the small intestine that are beyond the reach of other tests. A relatively new diagnostic tool, the capsule – while traveling throughout the small intestine – sends video images of the lining of the small intestine to a receiver. This test is effective in identifying the early, mild abnormalities of Crohn’s disease, but cannot be performed where a small intestine obstruction is suspected as the capsule may become stuck en route.

Radiographic Tests

Much of the small intestine cannot be imaged by endoscopy. Radiology is used for this part of the GI tract:

X-rays – These can detect blockages in both the small and large intestine. Small bowel X-rays can assist in pinpointing areas of inflammation or narrowing in the small bowel, symptoms associated with Crohn’s disease.

X-rays with barium liquid contrast – This technique is used with endoscopy to both monitor and treat IBD. A chalky solution, barium, is drunk to coat the lining of the small intestine. Barium appears white on X-ray film, revealing inflammation and/or other intestinal abnormalities.

Barium can also be administered via the rectum. Referred to as a

barium enema

, this procedure is used to collect X-ray images of the colon and the terminal ileum, revealing ulcerations, narrowing, and bowel fistulae.

Computerized tomography scans (CT or CAT) – A specialized X-ray technique capable of collecting more detail than a standard X-ray, CT scans examine the entire bowel as well as tissues outside the bowel that can’t be viewed with other tests. Especially helpful in detecting abscesses, fistulas, and blockages, this technique is used to determine the location and severity of Crohn’s disease.

Click inflammatory bowel disease to read more on diagnosing Crohn’s disease and ulcerative colitis.

Treating Crohn’s Disease

While there is no cure for Crohn’s disease, treatment can be effective at reducing the number of flare-ups a sufferer must endure. Treatment depends on disease location and severity, complications, and the patient’s response to medication. Crohn’s disease normally recurs at various times throughout the sufferer’s lifetime, but some individuals experience years of symptom-free remission.

Crohn’s disease treatment goals include,

  • Relieving symptoms such as abdominal pain, diarrhea, and rectal bleeding
  • Controlling inflammation
  • Correcting nutritional deficiencies
  • Inducing and maintaining remissions
  • Minimizing treatment side effects
  • Optimizing quality of life

IBD treatment includes medications, dietary and lifestyle changes, and surgery.


The effect of Crohn’s disease medications varies considerably; what works for one person, may not work at all for another. It can take time to discover and put an effective treatment plan into place. Side effects are also a consideration when deciding on a comfortable, effective Crohn’s disease treatment course of action.

Medications for treating Crohn’s include anti-inflammatory agents such as aminosalicylates, corticosteroids, and antibiotics; immune system suppressors
such as infliximab (Remicade); immunomodulators / biologic therapies (TNF inhibitors); and other medications such as anti-diarrheal [i.e. atropine (Lomotil) or loperamide (Imodium)] and fluid replacements, fiber supplements such as psyllium powder, laxatives, and pain relievers.

Infliximab (Remicade) – an immune system suppressor – was approved by the U.S. Food and Drug Administration (FDA) in 1998 specifically for moderate to severe Crohn’s disease. An antibody, it blocks the body’s inflammation response by neutralizing tumor necrosis factor (TNF), a protein produced in the immune system. Prescribed when standard Crohn’s disease therapies are ineffective, infliximab is also extremely effective for treating fistulas.

Budesonide (Entocort EC) – a relatively new type of corticosteroid – is an anti-inflammatory Crohn’s disease treatment. Unlike other corticosteroids, budesonide acts topically via direct contact with inflamed intestinal tissue. As soon as it’s absorbed into the body, the liver converts this potent corticosteroid into inactive chemicals. For this reason, budesonide has fewer side effects than other, systemic corticosteroids. Budesonide is most effective when treating Crohn’s terminal ileitis: Crohn’s disease limited to the terminal ileum.

TPN (total peripheral nutrition) or special high-calorie liquid intravenous nutrition formulas are sometimes recommended, especially for children whose development has been delayed. To facilitate temporary additional nutrition for those whose intestines need a rest or for people who are suffering from mal-absorption, intravenous feeding may be indicated.

Click inflammatory bowel disease to read more about medications for Crohn’s disease.

Dietary and Lifestyle Changes

To help minimize symptoms and increase the time between flare-ups, diet and lifestyle changes can be effective.

An appetite decrease is common with Crohn’s disease sufferers. This – along with poor absorption –can drastically reduce their ability to receive adequate daily nutritional requirements. For this reason, it is crucial that Crohn’s disease patients take special care to ensure a nutritious diet as well as to avoid foods that seem to trigger or worsen symptoms.


Some foods aggravate Crohn’s disease symptoms.7

Avoid problem foods: gassy foods such as beans, cabbage, cauliflower, and broccoli; raw fruit juices and fruits — especially citrus fruits — spicy food, popcorn, alcohol, caffeine, and foods and drinks that contain caffeine, such as chocolate and soda. Some people find very crunchy foods such as raw apples and carrots especially problematic.

Dairy products: Crohn’s disease sufferers are sometimes lactase deficient (the enzyme that breaks down milk products) and, therefore, find low lactose diets or the use of an enzyme product, such as Lactaid, helpful. Substitute yogurt and/or low-lactose cheeses, such as Swiss and cheddar, for milk.

Experiment with fiber: fiber may make diarrhea, pain, and gas worse, especially for those with small intestinal disease. If raw fruits and vegetables are irritating, steam, bake, or stew them.

Try low-fat foods: With Crohn’s disease of the small intestine, digesting and absorbing fat is sometimes difficult, so it passes through the intestine, worsening diarrhea. Butter, margarine, peanut butter, nuts, mayonnaise, avocados, cream, ice cream, fried foods, chocolate, and red meat can be especially problematic.

Eat small meals: five or six small meals rather than two or three larger ones are preferable.


Prebiotics and probiotics – as well as fish oil – are effective treatment alternatives for some Crohn’s disease sufferers.

An inflamed ileum (as with Crohn’s enteritis or Crohn’s terminal ileitis) interferes with absorption of vitamin B12 and bile salts. With inflammation along the length of the small intestine, absorption of all food is impaired

Iron supplementation (folate), vitamin B12, and calcium and vitamin D together are helpful if mal-absorption is a problem. Vitamin and mineral supplements and/or occasional vitamin injections can ease with nutritional deficiencies.

A multi-vitamin, including folic acid and vitamin C supplementation is sometimes necessary to combat possible deficiencies resulting from reducing fruit and vegetable consumption. In addition, magnesium and calcium deficiency is sometimes a factor for Crohn’s disease sufferers who experience greasy stools (steatorrhoea).

Click to read about IBD, and the effects of mal-absorption.


Some people with Crohn’s disease report flare-ups when they find themselves in a range of stressful situations from minor, everyday problems through to the death of a loved one; others report an overall increase in stress levels from constantly coping with illness.

If a connection between stress levels and the worsening of symptoms is apparent, learning to manage stress is vital. Basic things – such as eating properly and getting sufficient rest – help to ease stress.

Some people also find that exercising and learning relaxation techniques (slow breathing; biofeedback; relaxation and breathing exercises such as yoga and meditation; and hypnosis) can go a long way toward fostering overall relaxation and – by extension – help relax abdominal muscles.

Setting aside enough time each day to do something relaxing (a long bath, a walk in the woods, watching a movie) is also helpful.


Up to seventy-five percent of Crohn’s disease sufferers eventually require surgery;8 a great many of them will go on to have second operation, and others may even require a third.

Crohn’s disease surgery is most often performed to remove a diseased segment of the small intestine that is causing obstruction; drain pus from abdominal abscesses and those around the rectum; to treat severe anal fistulae that aren’t responding to drugs; and/or to resection internal fistulae (such as a fistula between the colon and bladder) that are causing infections.9

Complications such as intestinal bleeding and/or perforation are also treated with surgery, as are some symptoms that don’t respond to medication.

A common surgery performed on Crohn’s disease patients is strictureplasty, which is the shortening and widening of narrowed bowel segments that have developed as a result of built up scar tissue in the intestinal wall.

Some Crohn’s disease patients with large intestine disease require the removal of the entire colon. This is known as a colectomy. Afterwards, the bowel is either reconnected, or the surgeon creates an ostomy, which is an opening of the bowel on the abdominal wall to allow bowel contents to exit the body.

Crohn’s disease patients who’ve had part of their bowel removed may also require an ostomy.

Removing diseased portions of the intestine can lead to several years free of disease. Surgery can result in an extraordinary improvement in a Crohn’s disease sufferer’s quality of life.

Click inflammatory bowel disease to read more about surgery for Crohn’s disease.