Crohn's Disease

Crohn’s disease is a chronic disorder that causes inflammation of the gastrointestinal (GI) tract. Crohn’s disease can affect any area of the GI tract, from the mouth to the anus, but it most commonly affects the lower part of the small intestine, called the terminal ileum. The swelling extends deep into the lining of the affected organ. The swelling can cause pain and can make the intestines empty frequently, resulting in diarrhea. Crohn’s disease is classified as an inflammatory bowel disease, the general name for diseases that cause swelling in the intestines.

Because the symptoms of Crohn’s disease are similar to other intestinal disorders, such as irritable bowel syndrome and ulcerative colitis, it can be difficult to diagnose. Ulcerative colitis causes inflammation and ulcers in the top layer of the lining of the large intestine. In Crohn’s disease, all layers of the intestine may be involved, and normal healthy bowel can be found between sections of diseased bowel.

The cause of Crohn’s disease is unknown. The human immune system is made from cells and different proteins that protect people from infection. The most popular theory is that the body’s immune system reacts abnormally  to healthy intestinal bacteria, foods, and other substances and attacks these “invaders.” During this process, white blood cells accumulate in the lining of the intestines, producing chronic inflammation, which leads to ulcerations and bowel injury. Scientists do not know if the abnormality in the functioning of the immune system in people with Crohn’s disease is a cause, or a result, of the disease.

Research shows that the inflammation seen in the GI tract of people with Crohn’s disease involves several factors: the genes the patient has inherited, the immune system itself and the environment. Foreign substances, known as antigens, are found in the environment. One possible cause for inflammation may be the body’s reaction to these antigens, or that the antigens themselves are the cause for the inflammation. Some scientists think that a protein produced by the immune system, called anti-tumor necrosis factor (TNF), may be a possible cause for the inflammation associated with Crohn’s disease.

Statistics
Crohn’s disease affects men and women equally and seems to run in some families. About 20 percent of people with Crohn’s disease have a blood relative with some form of inflammatory bowel disease, most often a brother or sister and sometimes a parent or child. Crohn’s disease can occur in people of all age groups, but it is more often diagnosed in people between the ages of 20 and 30. People of Jewish heritage are at increased risk of developing Crohn’s disease while African Americans are at decreased risk.

Symptoms

The most common symptoms of Crohn’s disease are abdominal pain, often in the lower right area, and diarrhea. Rectal bleeding, weight loss, arthritis, skin problems and fever may also occur. Bleeding may be serious and persistent, leading to anemia. Children with Crohn’s disease may suffer delayed development and stunted growth. The range and severity of symptoms varies.

What are the complications of Crohn’s disease?

The most common complication is blockage of the intestine that occurs because the disease tends to thicken the intestinal wall with swelling and scar tissue, narrowing the passage. Crohn’s disease may also cause sores, or ulcers, that tunnel through the affected area into surrounding tissues. The tunnels, called fistulas, are a common complication and often become infected. Sometimes fistulas can be treated with medicine, but in some cases they may require surgery. In addition to fistulas, small tears called fissures may develop in the lining of the mucus membrane of the anus.

Nutritional complications are common in Crohn’s disease. Deficiencies of proteins, calories, and vitamins are well documented. These deficiencies may be caused by inadequate dietary intake, intestinal loss of protein, or poor absorption, also referred to as malabsorption.

Other complications associated with Crohn’s disease include arthritis, skin problems, inflammation in the eyes or mouth, kidney stones, gallstones, or other diseases of the liver and biliary system. Some of these problems resolve during treatment for disease in the digestive system, but some must be treated separately.

[source: National Digestive Diseases Clearinghouse (NNDIC)]

Other Resources

CCFA The Crohn's and Colitis Foundation of America is a nonprofit, volunteer-driven organization dedicated to finding the cure for Crohn's disease and ulcerative colitis.

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