What is inflammatory bowel disease?
Inflammatory bowel disease (IBD) is a group of chronic disorders that affect one to two million people in the United States. Characterized by swollen and damaged tissues in the lining of the intestinal tract, these conditions vary in severity from person to person and change over time. Periods of active disease may alternate with periods of remission. During a flare-up, a person may experience frequent bouts of watery and/or bloody diarrhea, abdominal pain, weight loss, and fever. Between these flare-ups, symptoms frequently diminish. Many people may go through extended periods of remission between flare-ups.
The cause of IBD is not known, but these diseases are thought to be due to an autoimmune process that has been triggered by a genetic predisposition, a viral illness, and/or an environmental factor. IBD affects both sexes equally and is seen most frequently in Caucasians who live in industrialized countries. The most common inflammatory bowel diseases are Crohns disease (CD) and ulcerative colitis (UC). Either may affect anyone at any age, but the majority of cases are first diagnosed in people 15 to 35 years of age, and a smaller number of cases diagnosed between the ages of 50 and 70. In addition to gastrointestinal symptoms, children affected by CD or UC may experience delayed development and growth retardation. Those who are diagnosed with one of these conditions at a young age are also at an increased risk of developing colon cancer later in life.
Crohns disease can affect any part of the gastrointestinal tract from the mouth to the anus but is primarily found in the last part of the small intestine (the ileum) and/or in the colon (large intestine or bowel). With CD, affected bowel tissue may be in patches with normal tissue in between. Inflammation may penetrate deep into the tissues of the intestines/colon and form ulcers or fistulas, tunnels through the intestines that allow waste material to move into other areas. Other complications of CD may include bowel obstructions, anemia from bleeding tissues, and infections. According to the Crohn's & Colitis Foundation of America, about two-thirds to three-quarters of those with Crohns disease will eventually require surgery, either to remove damaged sections of the intestines/colon or to treat an obstruction or fistula.
Ulcerative colitis primarily affects the surface lining of the colon. Although the symptoms may be similar to those seen with CD, the tissue inflammation caused by UC is continuous, not patchy, and usually starts from the anus and moves up the colon. UC tends to present more frequently with bloody diarrhea. The most serious complication of UC is toxic megacolon, a relatively rare acute condition in which a section of the colon becomes essentially paralyzed. Waste does not move through the section; it accumulates and dilates the colon. This can cause abdominal pain, fever, and weakness and can become life-threatening if left untreated.