Ulcerative colitis is a chronic (ongoing), recurrent disease of the large bowel (colon)
causing inflammation and sores (ulcers) of the mucosal lining.
The disease usually starts in the lower part of the colon called rectum and may involve
the entire colon (pan-colitis).
Ulcerative colitis belongs to a class of intestinal disorders, collectively called
inflammatory bowel disease, which includes Crohn's disease (see
tutorial).
Unlike Crohn's disease that may affect the entire digestive tract and also extraintestinal
sites, ulcerative colitis is localized to the colon.
In contrast to Crohn's disease, ulcerative colitis involves the rectum and the colon in a
continuous manner.
It is estimated that about 500,000 people are affected by ulcerative colitis in
America.
There are two incidence peaks. Most commonly the disease affects young people between 10
and 30 years of age. A second peak occurs in people between 50 and 70 years of age. Women
and men appear to be affected equally.
It is not known what triggers ulcerative colitis. The disease can run in the families, but
there is no typical pattern of inheritance and no responsible gene has yet been
discovered.
It is believed that ulcerative colitis, like Crohn's disease, is a disorder of the immune
system, but it is not known whether the immune abnormality is the cause or a result of the
ongoing inflammation. Many researchers believe that the interaction between an ingested
foreign substance (antigen) with the body's defense system may trigger an ongoing
inflammation.
The most common symptoms of ulcerative colitis are crampy abdominal pain and bloody
diarrhea. These symptoms may have a sudden (acute) or gradual onset and may be quite
severe in about half of the patients depending on the extent of the colonic inflammation.
Other symptoms may include fatigue, weight loss, loss of appetite and failure to grow in
children. If the rectal bleeding is severe, anemia will develop.
These symptoms may spontaneously remit, and the patients may be symptom-free for variable
periods of time ranging from a few months to years.
The disease may have extraintestinal manifestations including skin lesions, eye
inflammation, joint pain, osteoporosis, and liver disorders.
The diagnosis of ulcerative colitis may be suspected from the clinical presentation and
the physical exam. To confirm this diagnosis, physicians order a series of tests including
blood tests (to check for anemia and for indicators of inflammation such as high white
cell count), stool culture (to exclude an intestinal infection) and a colonoscopy.
During a colonoscopy, a thin flexible tube equipped with a tiny video camera is inserted
into the rectum and colon after adequate bowel preparation. The video camera captures the
images of the inner surface (mucosa) and transmits them to a video monitor. The doctor
will examine the images and identify the severity and the extent of the disease. Small
tissue samples (biopsies) can be taken at the time of colonoscopy and sent to the
pathology laboratory for microscopic examination and diagnosis.
Ulcerative colitis is a chronic (ongoing) illness with alternating periods of active
disease (flares) and periods of remission (no symptoms).
Complications are common and may include severe bleeding from deep ulcers, perforation,
marked abdominal distention caused by the inflammation involving the entire bowel wall
resulting in colonic dilatation, constipation and fever (toxic megacolon).
In some patients that do not respond to the standard medical treatment, the inflammation
may induce premalignant changes of the mucosa called dysplasia that may evolve into a
malignant growth called adenocarcinoma. Therefore, it is recommended that a set of
patients with ulcerative colitis be screened by colonoscopy for colorectal adenocarcinoma.
There are several approaches to the therapy of ulcerative colitis: medical treatment,
surgical treatment and nutrition.
There is currently no medical cure for ulcerative colitis. The aim of the medical
treatment is to induce and maintain remission by markedly decreasing the inflammatory
process.
Three types of drugs are routinely used depending on the severity of the disease:
· Aminosalicylates
These drugs are effective in treating milder forms of ulcerative colitis and include
sulfasalazine, mesalamine, olsalazine and balsalazide. The latter three drugs have fewer
side effects compared with sulfasalazine. These drugs may be given orally, through an
enema or in suppositories, depending on the extent and distribution of the disease.
· Corticosteroids
Examples of corticosteroids include prednisone, methylprednisolone and budesonide. These
drugs are effective in treating moderate forms of disease or in the patients that do not
respond to aminosalicylates. The side effects may be more serious and include weight gain,
hypertension, mood swings and increased risk for infection. Therefore, these drugs are not
administered long-term.
· Immunomodulators
These drugs alter the interaction between the immune system and the inflammation and are
used in certain patients that do not respond to the first line of antiinflammatory drugs.
Examples of immunomodulators include azathioprine and 6-mercapto-purine. Their side
effects may be serious and include hepatitis, pancreatitis and an increased risk for
infection. Immunomodulators are administered orally and may take a few months before the
full benefit is seen.
Some patients with ulcerative colitis fail to respond to the medical treatment and may
require surgery to remove the colon (colectomy). This procedure may become necessary in
order to avoid massive bleeding, colon rupture and the risk of cancer. However, most
people with ulcerative colitis will not need surgery.
A new surgical procedure (ileoanal anastomosis) is currently offered and it involves
removal of the colon and rectum (the lower part of the colon) with the creation of a pouch
from a loop of small bowel. This will help preserve the integrity of the bowel function
and will eliminate the need for an ileostomy (an opening in the abdominal wall through
which the small bowel content is emptied into an external pouch).
Unlike Crohn's disease, the patients with ulcerative colitis are cured after surgery and
most people will be able to lead a normal life.
The role of nutrition in the medical management of ulcerative colitis becomes important
particularly during the flare episodes. Restricting certain foods (milk, high-fiber, raw
vegetables, fruit and spicy foods) may help ease the symptoms.
CROHN'S and COLITIS FOUNDATION of
AMERICA (CCFA)
NATIONAL INSTITUTE of
DIABETES and KIDNEY DISEASE
