Professor Andrea Lorincz
April 30, 2013
“Irritable Bowel Disease”
More than 1.5 million Americans have Crohn's disease or ulcerative colitis, the most common forms of inflammatory bowel disease. Both conditions inflame the lining of the intestine, leading to bouts of watery diarrhea, rectal bleeding, abdominal cramps and pain, fever, and weight loss. Crohn's disease can occur anywhere in the digestive tract, often spreading deep into the layers of affected tissues. Ulcerative colitis usually affects only the innermost lining of the large intestine and rectum. Pouchitis, which can cause symptoms similar to those of ulcerative colitis, is a complication that develops in some people who have their colon and rectum removed and a pouch created for processing wastes. Microscopic colitis primarily affects older women and causes watery diarrhea that may persist for years. The term inflammatory bowel disease (IBD) covers a group of disorders in which the intestines become inflamed (red and swollen), probably as a result of an immune reaction of the body against its own intestinal tissue. Two major types of IBD are described: ulcerative colitis (UC) and Crohn's disease (CD). As the name suggests, ulcerative colitis is limited to the colon (large intestine). Although Crohn's disease can involve any part of the gastrointestinal tract from the mouth to the anus, it most commonly affects the small intestine and/or the colon. Both ulcerative colitis and Crohn's disease usually run a waxing and waning course in the intensity and severity of illness. When there is severe inflammation, the disease is considered to be in an active stage, and the person experiences a flare-up ofthe condition. When the degree of inflammation is less (or absent), the person usually is without symptoms, and the disease is considered to be in remission.
I. Etiology The etiology of Irritable Bowel Syndrome for the most part is unknown, however a couple other factors are common in patients: abnormalities in the nervous system or colon and abnormal serotonin levels. It's not known exactly what causes irritable bowel syndrome. The walls of the intestines are lined with layers of muscle that contract and relax in a coordinated rhythm as they move food from your stomach through your intestinal tract to your rectum. If you have irritable bowel syndrome, the contractions may be stronger and last longer than normal. Food is forced through your intestines more quickly, causing gas, bloating and diarrhea. In some cases, the opposite occurs. Food passage slows, and stools become hard and dry. Abnormalities in your nervous system or colon also may play a role, causing you to experience greater than normal discomfort when your intestinal wall stretches from gas. There are a number of other factors that may play a role in IBS. For example, people with IBS may have abnormal serotonin levels. Serotonin is a chemical messenger that's normally associated with brain function, but it also plays a role in normal digestive system function. It's also possible that people with IBS don't have the right balance of good bacteria in the intestine.
II. Signs & Symptoms Signs and symptoms are a wide range of abdominal pain and abnormalities, they vary from mild to severe, and may be active constantly or sparsely. The signs and symptoms of irritable bowel syndrome can vary widely from person to person and often resemble those of other diseases. Among the most common are abdominal pain or cramping, a bloated feeling, gas (flatulence), diarrhea or constipation – sometimes even alternating bouts of constipation and diarrhea, and mucus in the stool. Like many people, a person may have only mild signs and symptoms of irritable bowel syndrome. However, sometimes these problems can be disabling. Intestinal Blockage. Blockage or obstruction in the intestinal tract is a common complication of