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 digested; the long, small bowel, where nutrients, calories, and vitamins are absorbed; and the colon and rectum, where water is absorbed and stool is stored. The two primary sites for Crohn's disease are the ileum, which is the last portion of the small bowel (ileitis, regional enteritis), and the colon (Crohn's colitis). The condition begins as small, microscopic nests of inflammation which persist and smolder. The lining of the bowel can then become ulcerated and the bowel wall thickened. Eventually, the bowel may become narrowed.
What Causes Crohn's Disease?
After many years of intense research, the cause of Crohn's disease is still unknown. One theory is that the condition is caused by an unidentified, slow-growing microorganism. The body's immune system, which protects it against many different infections, is also known to be a factor. In spite of the unknown cause, enormous understanding and knowledge currently exists about the disease and its treatment.
Who Develops Crohn's Disease?
The condition occurs in both sexes and among all age groups, although it most frequently begins in young people. For unknown reasons, Jewish people are at increased risk of developing Crohn's, while African Americans are at decreased risk.
The symptoms of Crohn's disease depend on where in the intestinal tract the disorder first 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 (which is sometimes bloody) may occur, as well as fever and weight loss.
When the inflammation is active, fatigue and lethargy appear. In children and young adults there may be difficulty gaining or maintaining weight.