Conditions that affect the ability of the digestive
tract to absorb nutrients and water have a particularly significant impact
on health. The most common of these conditions is Inflammatory Bowel Disease
(IBD), which, in severe cases, may result in SBS. IBD includes both ulcerative
colitis and Crohn's disease (CD). Ulcerative colitis affects the mucosa
of the colon, and does so in a continuous pattern, beginning in the rectum
and spreading to other segments of the colon. CD extends beyond the mucosa
and involves all layers of the walls of the bowel, potentially affecting
both the small and large intestine. It is estimated that there are up
to one million people in the U.S. with IBD.
Crohn's disease is the most common cause of SBS, particularly
in the form called regional enteritis (inflammation of the intestine),
which affects the farthest (distal) end of the ileum and essentially destroys
its function. The inflammation that results from CD can cause abdominal
pain and diarrhea. Other symptoms include rectal bleeding, weight loss,
and fever. If the bleeding is severe and persistent, anemia may result.
This disease affects men and women equally and seems to have a hereditary
component. Even though CD afflicts people of all ages, it is most often
diagnosed in teenagers and young adults. The exact cause of the disease
has not been determined, but a popular theory is that the body's immune
system reacts to a virus or bacterium and causes the inflammation in the
intestine. Ulcerative colitis less often results in SBS because surgical
procedures to treat it generally remove the colon and are much less likely
to involve the small bowel than surgical treatments for CD.
The use of chemo- and radiation therapies and nonsteroidal
anti-inflammatory drugs (NSAIDs) can also lead to damage in the intestine.
In some cases, this damage can be so severe that removal of all or part
of the intestine is required. Other causes of SBS include trauma to the
small bowel as a result of injury, obstructions of the bowel caused by
other conditions or tumors, cancer of the small bowel, and blockage of
blood flow (ischemia) to the bowel that is caused by several possible
conditions.
This information
is provided as a general educational service
and is not intended to recommend any particular treatment plan
or to replace the advice of physicians. It is important that patients
seek and rely on the advice of a healthcare professional
about their individual medical conditions.
