The most common complication of small bowel Crohn's disease is bowel obstruction due to swelling.
According to gastroenterologist Fred Saibil, M.D., in his book Crohn's Disease and Ulcerative Colitis: Everything You Need to Know, the normal intestine may be thought of as a stretchy elastic band: it has a thin wall and a large opening compared to the thickness of that wall.
However, in a patient with small bowel Crohn's, the wall becomes swollen due to chronic inflammation. Not only does it swell outward, it swells inward too.
"Now," says Dr. Saibil, "the intestine is more like a tire," with a thicker, somewhat stiffer wall and a much narrower channel.
Other Types of Blockages
The chronic intestinal inflammation that characterizes Crohn's disease may also lead to the development of scar tissue in the intestinal tract.
As the cycle of inflammation and scarring continue, a segment of the tract may be become narrowed in what is known as a stricture (sometimes called stenosis). If a stricture narrows far enough, it may eventually obstruct the intestinal tract.
Alternately, if a person with an intestinal stricture eats something that is difficult to digest—for instance, raw vegetables, popcorn, or nuts—the food itself may lead to a bowel obstruction. Acute inflammation on top of a stricture may cause the intestine to become blocked as well.
Because Crohn's disease affects the entire thickness of the bowel wall, strictures are much more common than they are in ulcerative colitis, which typically affects only the inner lining. With strictures, bowel obstructions may be either acute (temporary) or chronic (permanent).
Adhesions are bands of scar tissue that develop normally after a patient has surgery on the gastrointestinal (GI) tract.
Adhesions will run from the point of the surgery to other parts of the intestine, other organs, or to the lining of the abdominal cavity (the peritoneum).
For most people, adhesions are painless and don't cause any problems at all. However, for some patients, the adhesion may cause the intestine to become "fixed." If a fixed intestine becomes twisted, it will cause an obstruction.
Most bowel obstructions caused by adhesions will get better without surgery, although, rarely, surgery will be required to cut the adhesions and untwist the bowel. New adhesions will form but will likely not cause problems.
The symptoms of a chronic blockage will be a "crampy" abdominal pain, bloating, and nausea, which occur shortly after a meal. The elapsed time between the meal and the symptoms will determine the site of the blockage.
If it’ is less than one hour, the small bowel (intestine) is usually the culprit. Longer than one an hour suggests the blockage is in the colon. If the symptoms happen all or most of the time after eating, it’ is likely the patient is dealing with strictures as well as swelling.
In addition to the other symptoms, vomiting, increased diarrhea, or , alternately, constipation, may sometimes occur as well.
A person with acute small bowel obstruction will usually get better within 48 hours of beginning a clear fluid diet or taking prednisone ( a powerful anti-inflammatory).
In more serious cases, steroids and a sterilized liquid (enteral) diet will usually help to reduce the swelling.
However, when the blockage is predominantly due to strictures, drugs—, if they work at all—, are usually of limited effectiveness. In those more serious cases, the first option for many patients is an endoscopy.
In an endoscopy, a doctor passes an inflatable balloon through an endoscope, thus dilating the area of scarring. Success rates are as high as 75 percent with this procedure. An endoscopy may relieve symptoms for weeks, months, or even years for some people.
However, if the area isn't accessible with an endoscope, surgery will be necessary.
The two types of surgery performed on patients with small bowel Crohn's are resection, which involves removing the scarred area of the intestine, and strictureplasty, which, says Dr. Saibil, may be thought of as "plastic surgery on the intestine." says Dr. Saibil,
The two types of Crohn's patients who are candidates for strictureplasty include those who have had a previous resection, or for those for whom the disease is very extensive. Many of those who receive strictureplasty are able to stop taking medications that help heal residual disease and maintain remission of Crohn's.
Strictures that are opened with strictureplasty usually remain open as well, and patients will generally only require surgery again if new strictures form elsewhere. In addition, most people will begin to eat normally and even gain weight after the operation.