What is Crohn's Disease?

Crohn's disease is part of chronic inflammatory bowel disease. Another name for that disease is Regional Enteritis. Crohn's disease is a nonspecific granulomatous inflammatory disease affecting the lower end of the ileum and often involving the colon and other parts of the intestinal tract. Crohn's and other irritable bowel diseases are associated with a strong familial pattern. Approximately 15% of patients with Crohn's have first-degree relatives who also have Crohn's. The incidence of Crohn's among first degree relatives of Crohn's is 30 to 100 times greater than the general population. The genetic factors play a significant role in Crohn's pathogenesis. It has been suggested that there may be 10 to 15 genes which any account for susceptibility to Crohn's or other irritable bowel diseases.

Symptoms and Causes

Abdominal pain and diarrhea are the most common symptoms of Crohn's disease. Frequently, these problems follow a meal. Other signs include fever, joint pains, loss of appetite, and weight loss. Inflammation of the lining of the intestine, anal fissure (a tear or ulcer in the lining of the anal cavity), anal fistula (an abnormal channel formed between the anal canal and a tiny hole in the skin surround the anus), or an abscess may also develop. The disease usually first develops between ages 20 and 30. Although remission is possible the disease often continues intermittently throughout a person's life.

The cause is unknown. However doctors believe that an agent, such as a virus or bacterium, alters the body's immune system, triggering inflammation in the intestinal wall. Contributing factors may include genetic predisposition, diet, and stress. Several complications occur far from the intestine, supporting the theory that there is an autoimmune component to this disease. Such complications any include sacrolitis (inflammation of the sacroiliac joint at the base of the back), spondylitis (a painful type of arthritis that affects the joints of vertebrae in the back), erythema nodosum (a skin condition in which red areas of swelling appear on the legs), and iritis (inflammation of the iris in the eye). When the symptoms of Crohn's disease subside, these conditions also generally improve.

Diagnosis

Diagnosis is based on a complete physical examination and tests, such as stool analysis, blood tests, a lower gastrointestinal (GI) series (an x-ray procedure also known as a barium enema) and sigmoidoscopy, or colonoscopy (examinations of the rectum and colon using flexible viewing tubes passed through the anus). It can be difficult to differentiate between Crohn's and ulcerative colitis. Crohn's disease is slight less common than ulcerative colitis in the United States.

Treatment

Treatment is with anti-inflammatory drugs. The goal of both aspirin-based anti-inflammatory drugs, such as sulfasalazine and corticosteroids, such as prednisone, is to suppress the inflammatory response so the body can heal itself. Powerful corticosteroids more successfully control stubborn cases of inflammation, but they also have many unwanted side effects. They include bloating, weight gain, brittle bones, nervousness, and insomnia. Immunosuppressant and antibiotics may also be prescribed. Severe attacks generally require hospitalization and intravenous administration of medication. If a great deal of blood has been lost, a transfusion may be required.

When medication cannot control the symptoms or a complication develops, a colectomy (surgical removal of all or part of the colon) becomes necessary. When only part of the colon is removed, the healthy remaining sections are joined to maintain a passageway for stool. When this is not possible, a colostomy is performed, in which an opening called a stoma is made in the abdominal wall to allow discharge of feces into an external bag. A similar procedure on the small intestine, or ileum, is known as an ileostomy. Colostomies and ileostomies can be temporary or permanent.

Source: AMA Complete Medical Encyclopedia, Copyright 2003, American Medical Association