Crohn's Disease
Crohn's disease is a chronic recurrent inflammatory
disease of the intestinal tract. Crohn's disease and
ulcerative colitis are together known as inflammatory
bowel disease. Crohn's disease can involve any part of
the gastrointestinal tract, including the mouth,
esophagus, stomach, and the small and large intestine.
The most common sites Crohn's disease occurs in are the
last portion of the small intestine (the ileum) and the
large intestine (the colon). Persistent inflammation in
the intestinal lining leads to ulceration and bleeding.
Some ulcers become deep enough to either perforate or to
tunnel into adjacent organs or the skin. The
inflammatory tracts created in this way are known as
fistulas. Alternatively, the inflammation may cause
enough thickening or scarring of the bowel wall to
create an obstruction.
TREATMENTS: Because Crohn's disease can involve
so many parts of the gastrointestinal tract and in
multiple ways, a complete discussion of treatment
options would be extremely long. Treatment in general
falls into a few categories:
Mesalamine: The
medications that contain mesalamine are commonly used in
milder forms of Crohn's disease. They are distinguished
from each other by their costs, their side effect
profile, and where they are released in the
gastrointestinal tract. Sulfasalazine (Azulfidine),
Colazal, and Dipentum are released only in the colon.
Asacol is released in the terminal ileum and colon.
Pentasa is released throughout the small intestine and
colon.
Antibiotics:
Antibiotics appear to reduce the bacterial contribution
to Crohn's disease and are commonly used sometimes for a
prolonged period. Among the most frequently used
antibiotics are used ciprofloxacin and metronidazole
(Flagyl).
Steroids:
Steroids such as prednisone are effective at inducing
remission in moderate to severely active Crohn's
disease. However, they have many side effects and should
be tapered and discontinued if possible as soon as
remission is achieved. Budesonide (Entocort) is a
steroid which is rapidly broken down by the liver so
that 90% of it never circulates throughout the rest of
the body. However, if used long enough it too can result
in similar steroid side effects.
Immunomodulators: For
those with more refractory disease, especially those who
cannot taper off steroids without a recurrence of their
disease, immunomodulators are generally used: most
commonly Imuran (azathioprine), 6-mercaptopurine
(Purinethol) or methotrexate. Although effective at
maintaining remission, these drugs take a long time to
produce their full effect (about 3 months) and require
periodic blood tests such as liver enzymes and white
blood cell counts. As with all medications, a thorough
discussion of side effects should be held with your
physician before beginning them.
Biologic Agents:
Infliximab (Remicade) is an antibody that neutralizes an
inflammatory substance in your body called TNF. TNF
appears important in perpetuating the chronic
debilitating inflammation that characterizes Crohn's
disease. Infliximab can be quite effective in
controlling the disease in patients who have failed to
respond to other treatments. It is given as an
intravenous infusion every 8 weeks and usually in
conjunction with an immunomodulatory agent such as those
listed above. Many other biologic agents are either
under investigation or are anticipated to be released
soon.
Surgery:
It is important to remember that surgery does not cure
Crohn's disease and that the disease may recur after
surgery in portions of the intestine that were
previously uninvolved. Therefore, surgery is generally a
last resort after medical therapy has failed.
Nevertheless, 80% of Crohn's disease patients will
undergo surgery at some time to close fistulas, bypass
obstructions, or remove refractory effective areas of
intestine.