Ulcerative Colitis
Ulcerative colitis is a chronic, episodic, inflammatory disease of the large intestine
and rectum characterized by bloody diarrhea.
Causes of Ulcerative Colitis
The cause is of ulcerative colitis is unknown. It may affect any
age group, although there are peaks at ages 15 to 30 and then again at ages 50 to 70.
The disease usually begins in the rectal area and may eventually extend through the
entire large intestine. Repeated episodes of inflammation lead to thickening of the wall
of the intestine and rectum with scar tissue. Death of colon tissue or sepsis may occur
with severe disease.
The symptoms vary in severity and their onset may be gradual or sudden. Attacks may be
provoked by many factors, including respiratory
infections or stress.
Risk factors include a family history of ulcerative colitis or Jewish ancestry. The incidence is 10 to
15 out of 100,000 people.
Information about Ulcerative Colitis
The primary problem in IBD is inflammation, as the name suggests. Inflammation is a
process that often occurs in order to fight off foreign invaders in the body, including
viruses, bacteria, and fungi. In response to such organisms, the body's immune system
begins to produce a variety of cells and chemicals intended to stop the invasion. These
immune cells and chemicals, however, also have direct effects on the body's tissues,
resulting in heat, redness, swelling, and loss of function. No one knows what starts the
cycle of inflammation in IBD, but the result is a swollen, boggy intestine.
In ulcerative colitis, the inflammation affects the lining of the rectum and large
intestine. It is thought that the inflammation begins in the last segment of large
intestine, which empties into the rectum (sigmoid colon). This inflammation may spread
through the entire large intestine, but only rarely affects the very last section of the
small intestine (ileum). The rest of the small intestine remains normal.
Ulcerative colitis differs from Crohn's disease, which is a form of IBD that affects
both the small and large intestines. The inflammation of ulcerative colitis occurs only in
the lining of the intestine (unlike Crohn's disease which affects all of the layers of the
intestinal wall). As the inflammation continues, the tissue of the intestine begins to
slough off, leaving pits (ulcerations) which often become infected.
Like Crohn's disease, ulcerative colitis occurs in all age groups, with the most common
age of diagnosis being 15-35 years of age. Men and women are affected equally. Whites are
more frequently affected than other racial groups, and people of Jewish origin have 3-6
times greater likelihood of suffering from any IBD. IBD is familial; an IBD patient has a
20% chance of having other relatives who are fellow sufferers.
Symptoms of Ulcerative Colitis
- Diarrhea, from only a few episodes to very frequently throughout the day (blood and
mucus may be present)
- Abdominal pain and cramping that usually subsides after a bowel movement
- Abdominal sounds (borborygmus, a gurgling or splashing sound heard over the intestine)
- Fever
- Weight loss
- Foul-smelling stools
- Tenesmus
- Jaundice
No specific cause of ulcerative colitis has been identified. Although no organism
(virus, bacteria, or fungi) has been found to set off the cycle of inflammation that
occurs in ulcerative colitis, some researchers continue to suspect that some such organism
is responsible for initiating the cycle. Other researchers are concentrating on
identifying some change in the cells of the colon that would make the body's immune system
accidentally begin treating those cells as foreign invaders. Other evidence for such a
disorder of the immune system includes the high number of other immune disorders that tend
to accompany ulcerative colitis.
The first symptoms of ulcerative colitis are abdominal cramping and pain, a sensation
of urgent need to have a bowel movement (defecate), and blood and pus in the stools. Some
patients experience diarrhea, fever, and weight loss. If the diarrhea continues, signs of
severe fluid loss (dehydration) begin to appear, including low blood pressure, fast heart
rate, and dizziness.
Severe complications of ulcerative colitis include perforation of the intestine (in
which the wall of the intestine develops a hole), toxic dilation of the colon (in which
the colon become quite large in diameter), and the development of colon cancer.
Intestinal perforation occurs when long-standing inflammation and ulceration of the
intestine weakens the wall to such a degree that a hole occurs. This is a life-threatening
complication, because the contents of the intestine (which under normal conditions
contains a large number of bacteria) spill into the abdomen. The presence of bacteria in
the abdomen can result in a massive infection called peritonitis.
Toxic dilation of the colon is thought to occur because the intestinal inflammation
interferes with the normal function of the muscles of the intestine. This allows the
intestine to become lax, and its diameter begins to increase. The enlarged diameter thins
the walls further, increasing the risk of perforation and peritonitis. When the diameter
of the intestine is quite large, and infection is present, the condition is referred to as
"toxic megacolon."
Patients with ulcerative colitis have a significant risk of developing colon cancer.
This risk seems to begin around 10 years after diagnosis of ulcerative colitis. The risk
becomes statistically greater every year:
- At 10 years, the risk of cancer is about 0.5-1%.
- At 15 years, the risk of cancer is about 12%.
- At 20 years, the risk of cancer is about 23%.
- At 24 years, the risk of cancer is about 42%.
The overall risk of developing cancer seems to be greatest for those patients with the
largest extent of intestine involved in ulcerative colitis.
Patients with ulcerative colitis also have a high chance of experiencing other
disorders, including inflammation of the joints (arthritis), inflammation of the vertebrae
(spondylitis), ulcers in the mouth and on the skin, the development of painful, red bumps
on the skin, inflammation of several areas of the eye, and various disorders of the liver
and gallbladder.
Diagnosis of Ulcerative Colitis
Diagnosis is first suspected based on the symptoms that a patient is experiencing.
Examination of the stool will usually reveal the presence of blood and pus (white blood
cells). Blood tests may show an increase in the number of white blood cells, which is an
indication of inflammation occurring somewhere in the body. The blood test may also reveal
anemia, particularly when a great deal of blood has been lost in the stool.
The most important method of diagnosis is endoscopy, during which a doctor passes a
flexible tube with a tiny, fiberoptic camera device through the rectum and into the colon.
The doctor can then examine the lining of the intestine for signs of inflammation and
ulceration that might indicate ulcerative colitis. A tiny sample (biopsy) of the intestine
will be removed through the endoscope, which will be examined under a microscope for
evidence of ulcerative colitis. Because of the increased risk of cancer in patients with
ulcerative colitis, endoscopic exam will need to be repeated frequently. Biopsies should
be taken regularly, to closely monitor the intestine for the development of cancer or
precancerous changes.
X-ray examination is helpful to determine the amount of intestine affected by the
disease. However, x-ray examinations requiring the use of barium should be delayed until
treatment has begun. Barium is a chalky solution that the patient drinks or is
administered through the rectum and into the intestine (enema). The presence of barium in
the intestine allows more detail to be seen on x ray pictures. However, because of the
risk of intestinal perforation in ulcerative colitis, most doctors begin treatment before
stressing the wall of the intestine with the barium solution.
Treatment of Ulcerative Colitis
Treatment for ulcerative colitis addresses the underlying inflammation, as well as the
problems occurring due to continued diarrhea and blood loss.
Inflammation is treated with a drug called sulfasalazine, Sulfasalazine is made up of
two parts. One part is related to the sulfa antibiotics; the other part is a form of the
anti-inflammatory chemical salicylic acid (related to aspirin). Sulfasalazine is not
well-absorbed from the intestine, so it stays mostly within the intestine, where it is
broken down into its components. It is believed to be primarily the salicylic acid
component that is active in treating ulcerative colitis, by fighting inflammation. For
patients who do not respond to sulfasalazine, steroid medications (such as prednisone) are
the next choice.
Depending on the degree of blood loss, a patient with ulcerative colitis may require
blood transfusions and fluid replacement through a needle in the vein (intravenous or IV).
Medications that can slow diarrhea must be used with great care, because they may actually
cause the development of toxic megacolon.
A patient with toxic megacolon requires close monitoring and care in the hospital. He
or she will usually be given steroid medications through an IV, and may be put on
antibiotics. If these measures do not improve the situation, the patient will have to
undergo surgery to remove the colon. This is done because the risk of death after
perforation of toxic megacolon is greater than 50%.
Similarly, a patient with proven cancer of the colon, or even a patient who shows
certain signs thought to indicate a precancerous condition, will need his or her colon
removed. Removal of the colon is called a colectomy. When a colectomy is performed, a
piece of the small intestine (ileum) is pulled through an opening in the abdomen. This bit
of intestine is fashioned surgically to allow a special bag to be placed over it, in order
to catch the body's waste (feces) which no longer can be passed through the large
intestine and out of the anus. This opening, which will remain for the duration of the
patient's life, is called an ileostomy.
Prognosis of Ulcerative Colitis
Remission refers to a disease becoming inactive for a period of time. The rate of
remission of ulcerative colitis (after a first attack) is nearly 90%. Those individuals
whose colitis is confined primarily to the left side of the large intestine have the best
prognosis. Those individuals with extensive colitis, involving most or all of the large
intestine, have a much poorer prognosis. Recent studies show that about 10% of these
patients will have died by 10 years after diagnosis. About 20-25% of all ulcerative
colitis patients will require colectomy. Unlike the case for patients with Crohn's
disease, however, such radical surgery results in a cure of the disease. |