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Dr. Ba Hoang on Crohn's disease and Ulcerative colitis

Inflammatory Bowel Disease:

Inflammatory Bowel Disease (IBD) consists of two separate diseases that cause inflammation of the bowel: Crohn disease and
ulcerative colitis. Crohn's disease and ulcerative colitis are chronic conditions that causes inflammation of the digestive or
gastrointestinal (GI) tract. Crohn's disease most commonly affects the end of the small intestine (the ileum) and the beginning of the
large intestine (the colon), it may involve any part of the GI tract. In ulcerative colitis, on the other hand, the GI involvement is limited to
the colon. The symptoms of these two illnesses are so similar and it is sometimes difficult to establish the diagnosis definitively.
Both illnesses do have one strong feature in common. They are marked by an abnormal response by the body's immune system. In
people with Crohn's disease, however, the immune system reacts inappropriately. Mistaking food, bacteria, and other materials in
the intestine for foreign or invading substances, it launches an attack. In the process, the body sends white blood cells into the lining
of the intestines, where they produce chronic inflammation. These cells then generate harmful products that ultimately lead to
ulcerations and bowel injury. When this happens, the patient experiences the symptoms of IBD.

What Are the Symptoms?

Persistent diarrhea (loose, watery, or frequent bowel movements), crampy abdominal pain, fever, and, at times, rectal bleeding:
These are the hallmark symptoms of Crohn's disease, but they vary from person to person and may change over time. Loss of
appetite and subsequent weight loss also may occur. However, the disease is not always limited to the GI tract; it can also affect the
joints, eyes, skin, and liver. Fatigue is another common complaint.

Some patients may develop tears (fissures) in the lining of the anus, which may cause pain and bleeding, especially during bowel
movements. Inflammation may also cause a fistula to develop. A fistula is a tunnel that leads from one loop of intestine to another,
or that connects the intestine to the bladder, vagina, or skin. Fistulas occur most commonly around the anal area. If this complication
arises, you may notice drainage of mucus, pus, or stool from this opening.

Symptoms may range from mild to severe. Because Crohn's is a chronic disease, patients will go through periods in which the
disease flares up, is active, and causes symptoms. These episodes are followed by times of remission-periods in which symptoms
disappear or decrease and good health returns. In general, though, people with Crohn's disease lead full, active, and productive
lives.

Types of Crohn's Disease and Associated Symptoms:

The symptoms and complications of Crohn's disease differ, depending on what part of the intestinal tract is inflamed. That's why it is
important for you to know which part of your intestine is affected by Crohn's disease. Your doctor may also refer to your illness by
various names based on the principal area involved. The following are five types of Crohn's disease, together with their presenting
symptoms:
•        Ileocolitis: The most common form of Crohn's, affecting the ileum and colon. Symptoms include diarrhea and cramping or pain
in the right lower part or middle of the abdomen. Often accompanied by significant weight loss.
•        Ileitis: Affects the ileum. Symptoms same as ileocolitis. Complications may include fistulas or inflammatory abscess in right
lower quadrant of abdomen.
•        Gastroduodenal Crohn's disease: Affects the stomach and duodenum (the first part of the small intestine). Symptoms include
loss of appetite, weight loss, and nausea. Vomiting may indicate that narrowed segments of the bowel are obstructed.
•        Jejunoileitis: Produces patchy areas of inflammation in the jejunum (upper half of the small intestine. Symptoms include
abdominal pain (ranging from mild to intense) and cramps following meals, as well as diarrhea. Fistulas may form.
•        Crohn's (Granulomatous) Colitis: Affects the colon only. Symptoms include diarrhea, rectal bleeding, and disease around the
anus (abscess, fistulas, ulcers). Skin lesions and joint pains are more common in this form of Crohn's than in others.

What Causes IBD?

Although considerable progress has been made in IBD research, investigators do not yet know what causes this disease. Studies
indicate that the inflammation in IBD involves a complex interaction of factors: the genes the patient has inherited, the immune
system, and something in the environment. Foreign substances (antigens) in the environment may be the direct cause of the
inflammation, or they may stimulate the body's defenses to produce an inflammation that continues without control. Researchers
believe that once the IBD patient's immune system is "turned on," it does not know how to properly "turn off" at the right time. As a
result, inflammation damages the intestine and causes the symptoms of IBD.

How Common is Inflammatory Bowel Disease (IBD)?

It is estimated that as many as one million Americans have IBD-with that number evenly split between Crohn's disease and
ulcerative colitis. Males and females appear to be affected equally. Crohn's disease may occur in people of all ages, but it is
primarily a disease of adolescents and young adults-affecting mainly those between 15 and 35. In another much smaller group of
patients, the disease develops between the ages of 50 and 70, a so-called "second wave." However, Crohn's disease can also
occur in people who are 70 or older and in young children as well. In fact, 10 percent of those affected-or an estimated 100,000-are
youngsters under the age of 18.

Who Gets IBD?

IBD tends to run in families, so we know that genes definitely play a role in the IBD picture. Studies have shown that about 20 to 25
percent of patients may have a close relative with either Crohn's or ulcerative colitis. If a person has a relative with the disease, his or
her risk is about 10 times greater than that of the general population. If that relative happens to be a brother or sister, the risk is 30
times greater. IBD also appears to affect certain ethnic groups more than others. For example, American Jews of European descent
are four to five times more likely to develop IBD than the general population. IBD has long been thought of as a disease
predominantly affecting whites; the prevalence rate (the number of people with a disease at a given time) among whites is 149 per
100,000. However, there has been a steady increase in reported cases of both Crohn's disease and ulcerative colitis among African
Americans. The prevalence rates among Hispanics and Asians are lower than those for whites and African Americans.
For reasons that are not yet clearly understood, IBD is largely a disease of the developed world-principally, the U.S. and Europe.
Similarly, Crohn's disease and ulcerative colitis are reported to be more common in urban than in rural areas, and in northern than
in southern climates. Moreover, the frequency of disease increases when specific groups of people move from underdeveloped to
developed countries, and vice versa.

How is Crohn's Disease Diagnosed?

There is no single test that can establish the diagnosis of Crohn's disease with certainty. To determine the diagnosis, physicians
evaluate a combination of information from the patient's history and physical exam. They examine the results of laboratory tests, X-
rays, and findings on endoscopy and pathology tests, and exclude other known causes of intestinal inflammation. X-ray tests may
include barium studies of the upper and lower GI tract. Endoscopy tests may include flexible sigmoidoscopy and, sometimes,
colonoscopy, which allow the doctor to directly examine the colon with a lighted tube that is inserted through the anus. During these
tests, biopsies may be obtained. This procedure involves the removal of a small piece of tissue for closer analysis. It is important to
make sure that an infection is not causing the patient's symptoms, so one routine test is to examine the stool for harmful organisms.
Because Crohn's disease often mimics other conditions and symptoms may vary widely, it may take some time to arrive at the
correct diagnosis.

What Medications are Used to Treat This Disease?

Because there is no cure for Crohn's disease, the goal of medical treatment is to suppress the inflammatory response.
Several groups of drugs are used to treat Crohn's disease today. They are:
1.        Aminosalicylates (5-ASA): This class of anti-inflammatory drugs typically are used to treat mild to moderate symptoms.
2.        Corticosteroids: Prednisone and methylprednisolone are available orally and rectally. Corticosteroids nonspecifically
suppress the immune system and are used to treat moderate to severely active Crohn's disease.
3.        Immune modifiers: Azathioprine (Imuran®), 6-MP (Purinethol®), methotrexate, infliximab (Remicade™). Immune modifiers are
used to help decrease corticosteroid dosage and also to heal fistulas
4.        Antibiotics: metronidazole, ampicillin, ciprofloxacin, others.

Two-thirds to three-quarters of patients with Crohn's disease will require surgery at some point during their lives. Surgery
becomes necessary in Crohn's disease when medications can no longer control the symptoms. The overall goal of surgery in
Crohn's disease is to conserve bowel and return the individual to the best possible quality of life.