Inflammatory Bowel Disease:
Frequently Asked Questions

Version 3.0
This document was last modified on 3/15/1997

Part 1 of 3

Commonly-used abbreviations in this FAQ:

IBD     inflammatory bowel disease- includes Crohn's Disease and ulcerative colitis
IBS     irritable bowel syndrome
UC      ulcerative colitis
CD      Crohn's Disease
CCFA    the Crohn's and Colitis Foundation of America
CCFC    Canadian Foundation for Ileitis and Colitis
UOA     the United Ostomy Association
NSAID   Non-steroidal, anti-inflammatory drug
TPN     Total parenteral nutrition
GI      Gastro-intestinal, i.e., pertaining to your digestive system


1.0 Digestive System Primer

The Digestive System is a complex system of organs responsible for converting the food we eat into the nutrients which we require to fuel our metabolism.  Here is a guide to the terminology used to describe the various components of the Digestive System.

The Digestive System in essence consists of a long tube which connects the mouth to the anus. The term Gastrointestinal (GI) tract refers to the entire system. Once food leaves your mouth it enters the first part of the GI tract which is called the esophagus and then the stomach. The food passes relatively quickly into the stomach where it pauses and is churned up with acid into very small particles. It then passes into the small intestine which is about 20 feet long. The main function of the small intestine is to absorb nutrients from the food particles that arrive from the stomach. The food is digested with the assistance of secretions from the liver, gall bladder and pancreas.

The term bowel is synomymous with intestine. The small intestine is therefore also referred to as small bowel. The small bowel has three parts; the part nearest the stomach is the duodenum, the next part is the jejunum and the third part that connects to the large intestine is the ileum. The last part of the ileum, known as the terminal ileum, is a frequent site of involvement in Crohn's disease.

The large intestine is more frequently referred to as the colon. The first part of the colon is called the cecum and the appendix is found there. The main function of the colon is to absorb water from the processed food residue that arrives after the nutrients have been absorbed in the small intestine. The last part of the colon is the rectum which is a reservoir for feces. Feces are stored here until it is convenient for their expulsion and the sphincter muscles of the anus then relax.


1.1 Q: What is Inflammatory Bowel Disease?

Inflammatory Bowel Disease (IBD) is an umbrella term referring to two chronic diseases that cause inflammation of the intestines: ulcerative colitis (UC) and Crohn's disease (CD).  Though UC and CD are different diseases they do have features in common but there are important distinctions also.  Frequently, the symptoms caused by UC and CD are similar.

Both diseases are chronic and most frequently have their onset in early adult life. Some patients have alternating periods of relative health (remission) alternating with periods of disease (relapse or flare), while other patients have continuous symptoms from continued inflammation.  Fortunately, as treatment has improved the proportion of people with continued symptoms appears to have diminished significantly .

The severity of the diseases varies widely between individuals. Some suffer only mild symptoms, but others have severe and disabling symptoms.  Some have a gradual onset of symptoms, some develop them suddenly. About half of patients have mild symptoms, the other half suffer frequent flare-ups. Medical science has not yet discovered a cause or cure, but numerous medications are now available to control symptoms with  many more on the horizon.

1.1.1 Q: What is ulcerative colitis?

Ulcerative colitis (UC) is an inflammatory disease of the large intestine, commonly called the colon. UC causes inflammation and ulceration of the inner lining of the colon and rectum. This inner lining is called the mucosa. Crohn's disease (CD) causes inflammation that extends into the deeper layers of the intestinal wall.

The inflammation of UC is usually most severe in the rectal area with severity diminishing (at a rate that varies from patient to patient) toward the cecum, where the large and small intestine join. Significant deviations from this pattern may be a clue to the physician to suspect CD rather than UC. Such deviations may include either "skip areas" and/or "sparing of the rectum". Skip areas are patches of healthy tissue separating segments of diseased tissue. They are often seen in CD, but rarely in UC. Inflammation of the rectum is called proctitis. Inflammation of the sigmoid colon (located just above the rectum) is called sigmoiditis. Inflammation involving the entire colon is termed pan-colitis.

The inflammation causes the colon to empty frequently resulting in diarrhea. As the lining of the colon is destroyed ulcers form releasing mucus, pus and blood.

UC is relatively common in the western world and at least 250,000 in the United States alone have the disease. It occurs most frequently in people ages 15 to 30 although children and older people occasionally develop the disease.

About 50% of patients are free of symptoms at any given time but the vast majority suffer at least one relapse in any 10 year period.

Drug treatment is effective for about 70-80% of patients; surgery becomes necessary in the remaining 20-30%.

1.1.2 Q: What is Crohn's disease?

Crohn's disease (CD) is an inflammatory process that can affect any portion of the digestive tract, but is most commonly seen (roughly half of all cases) in the last part of the small intestine otherwise called the terminal ileum and cecum. Altogether this area is also known as the ileocecal region. Other cases may affect one or more of: the colon only, the small bowel only (duodenum, jejunum and/or ileum), the anus, stomach or esophagus. In contrast with UC, CD usually doesn't affect the rectum, but frequently affects the anus instead.

1.1.3 Q: What is ileitis?

This is CD of the ileum which is the third part of the small intestine. At one time, CD was thought to affect only the ileum, and for this reason the name "ileitis" was at one time synonymous with CD but now simply refers to CD of the ileum.

1.1.4 Q: What is Crohn's colitis?

This is CD affecting part or all of the colon. This form comprises about 20% of all cases of CD. Various patterns are seen. In about half of these cases CD lesions may be seen throughout one continuous subsegment of the colon.  In another quarter, skip areas are seen between multiple diseased areas. In the remaining quarter, the entire colon is involved, with no skip areas.

Unlike UC, in which inflammation is usually confined to the inner mucosal surface, CD typically involves all layers of the affected tissues.

1.1.5 Q: What is ulcerative proctitis?

Ulcerative proctitis is a form of UC that affects only the rectum.

1.1.6 Q: What is Granulomatous colitis?

This is another name for Crohn's disease that affects the colon.

1.1.7 Q: What is Irritable Bowel Syndrome?

This is *NOT* a variant of UC and Crohn's. UC and Crohn's disease are defined by the presence of inflammation in the intestine. There is no inflammation in the intestine in Irritable Bowel Syndrome. Irritable Bowel Syndrome (IBS) is also known as Functional Bowel Syndrome (FBS), Functional Bowel Disease (FBD) or spastic colon . Older terms for IBS are
spastic or mucous colitis or even simply "colitis".  These terms are no longer used because they cause people to confuse IBS with UC.

IBS is characterized by a variety of symptom patterns which include diarrhea, constipation, alternating diarrhea/constipation and abdominal pain. Fever and/or bleeding are NOT features of IBS.

IBS is much more common than CD or UC and many people with symptoms of IBS do not seek medical attention. Some patients with Crohns or UC can also have concurrent IBS.

1.2 Q: What symptoms are experienced by IBD patients?

The most common symptom of both UC and CD is diarrhea, sometimes severe, that may require frequent visits to a toilet (in some cases up to 20 or more times a day). Abdominal cramps are often present, the severity of which may  be correlated with the degree of diarrhea present. Blood may also appear in the stools, especially with UC.

Fever, fatigue, and loss of appetite may accompany these symptoms (with consequent weight loss).

At times, some UC and CD patients experience constipation during periods of active disease. In CD this can result from a partial obstruction usually of the small intestine. In UC constipation is most often a consequence of inflammation of the rectum (also known as proctitis); the colon has a nervous reaction and stasis of stool occurs upstream .

Inflammation can affect gut nerves in such a way as to make the patient feel that there is stool present ready to be evacuated when there actually is not. That results in the symptom known as tenesmus where there is an uncomfortable urge to defecate but nothing comes out. The feeling of urgency to pass stool is a frequent consequence of proctitis also. Inability to retain stool is an extreme manifestation of urgency. It is important to bring these symptoms to the attention of your physician because they may improve dramatically with appropriate local therapy.

Pain usually results from intestinal cramping or inflammation causing reflex irritability of the nerves and muscles that control intestinal contractions. Pain may also indicate the presence of severe inflammation or the development of a complication such as an abscess or a perforation of the intestinal wall. Generally, new onset pain or a significant change in the character of pain should be brought to the attention of your physician.  The pain of CD is often in the lower right area of the abdomen. This is where the terminal ileum is located and pain there usually indicates inflammation of the terminal ileum.

Location and intensity of abdominal pain vary from patient to patient, depending upon the location and type of disease in the affected tissues. Because of a phenomenon known as "referred pain", the location where pain is produced may not be the same as the location where it is experienced.

1.2.1 Q: What are extra-intestinal manifestations of these diseases?

These are symptoms of IBD that occur outside of the digestive tract.

Many IBD patients experience a wide variety of extra-intestinal manifestations of their disease. The most common is joint pain due to inflammation of the joints (arthritis). Others include various types of eye inflammation (iritis, conjunctivitis and episcleritis), skin inflammation (erythema nodosum and pyoderma gangrenosum) liver inflammation (hepatitis and sclerosing cholangitis). Other diseases and complications may be associated with IBD but less frequently.

At present there is no satisfactory explanation for the occurence of these extra-intestinal complications of IBD. Some researchers consider them to be secondary to the primary disease, while others see both the extra-intestinal manifestations *and* the primary disease as symptoms of a "systemic" condition. Resolution of this will depend on clarification of the cause of IBD.

1.2.2 Q: What other complications can occur?

Fatigue is the most common complication. Fever usually indicates active disease and/or a complication such as an abscess. Severe diarrhea, blood loss or infection can lead to rapid heartbeat and a drop in blood pressure. Continued loss of small amounts of blood in the stool (which may not be visible) may lead to anemia (reduced blood count); this may result in
fatigue.

CD frequently results in the development of fistulas which are abnormal connections between loops of intestine. These may even involve other organs such as the urinary bladder or open onto the skin. CD inflammation also frequently results in the formation of scar tissue with narrowed segments known as strictures. These strictures frequently cause bowel obstructions the symptoms of which will depend on the severity. The presence of a significant stricture is a common reason for surgery in CD.

Hemorrhoid-like skin tags and anal fissures may also develop.

Growth may be retarded in children with both forms of IBD and/or there may be a delay in the onset of puberty.

1.2.3 Q: What is toxic megacolon?

Toxic megacolon is a severe dilation of the colon which occurs when inflammation spreads from the mucosa through the remaining layers of the colon. It is much more commonly a complication of UC though it can be seen occasionally in CD. The colon becomes paralyzed which can lead to it eventually bursting; this is known as a "perforation". Such perforation is a dire medical emergency with a 30% mortality rate. Many patients with toxic megacolon require surgery.

Anyone with UC or CD serious enough to be at risk for toxic megacolon should be hospitalized and closely monitored. Warning signs include abdominal pain/tenderness, abdominal distention, fever, large numbers of stools with obvious blood and a rapid (more than 100/minute) pulse rate.   Fortunately, this grave complication appears to be decreasing in frequency which probably reflects more effective treatment.

Use of certain drugs (opiates, opioids and/or antispasmodics) may predispose to this complication. This is one of the reasons that these drugs should be used very carefully in both UC and CD.

1.2.4 Q: What are fistulas and abscesses?

Fistulas are hollow tracts running from a part of one organ (such as the colon) to other organs, adjacent loops of bowel, and or the skin. They occur in CD as a result of deep ulceration.

Fistulas between loops of bowel can interfere with nutrient absorption.  This is especially true for fistulas between the small and large bowel. 

Fistulas can also become infected forming abscesses. Abscesses are collections of pus that may be accompanied by significant pain, and which can become life threatening emergencies. Simple treatment of abscesses resulting from fistulas can sometimes be accomplished via a procedure called "incision and drainage" (I/D), in which an incision is made, through which the abscess is drained. However this procedure does not deal with the underlying fistula which gave rise to the problem.  Accordingly, a more elaborate procedure, known as a fistulectomy, is usually necessary for more definitive treatment.

Fistulas are relatively common in CD patients and are very rare in patients with UC.

1.2.5 Q: What are strictures?

Patients with CD in the small intestine may develop bowel obstructions which can result in severe cramps and vomiting.  These obstructions can result from narrowing of the intestine due to inflammation as well as from scar tissue (stricture) from healed lesions. If the obstruction is a consequence of inflammation then it can usually be relieved by medical therapy such as steroids. However if the obstruction is due to a fibrous stricture then surgical resection may be necessary. In others, it may be possible to clear some of these obstructions via a technique known as stricturoplasty, which attempts to expand the narrowed segment of the intestine.

Strictures can also occur in the large intestine, but are much less common.

1.2.6 Q: What is the cancer risk in IBD patients?

For patients who have had UC longer than ten years, the risk of colon cancer is greater than that for comparable people without UC. There is data that suggests a risk of  5-10% at that point increasing to a range between 15 and 40% after 30 years, depending upon the particular study one looks at. If only the rectum and lower (sigmoid) colon are involved, the risk of cancer is not significantly increased.  Patients that exhibit dysplasia (pre-cancerous changes in cells that can be detected by a biopsy) are at much higher risk.

There is some data suggesting that the risk of colon cancer in patients with colonic CD is similar to that of UC patients with disease of similar extent.

Other cancers, such as lymphoma or carcinoma of the small intestine or anus, may be slightly more common in Crohn's disease but the risk is not high.

In the presence of longstanding (> 7-8 years) UC which involves more than the rectum and sigmoid colon or extensive Crohn's colitis then the consensus of informed medical opinion is that the patient should have a regular (yearly or every second year) screening colonoscopy to look for evidence of dysplasia. If that is found then the safest option is for a colectomy to be performed. This strategy does not guarantee that cancer can be avoided but seems to significantly increase the probability that it is not life threatening if and when it is detected.

1.2.6.1 Q: Are there other factors predisposing to the development of colon cancer?

Patients who have both UC and sclerosing cholangitis may be at even greater risk of developing colon cancer. Accordingly screening should be done with particular vigilance in these patients.

There is also some data suggesting that low folic acid levels may predispose to the development of colon cancer in UC patients. 

1.2.6.2 Q: Are there ways to reduce the risk of developing colon cancer?

The only certain way is to have a colectomy: in other words to have the colon removed surgically.

However, there is circumstantial evidence that taking 5-ASA drugs drugs such as azulfidine  [See Section 2.1.1] might reduce the risk of colon cancer also.

Also there is some data that eating a diet rich in fruit and vegetables (five servings a day) and low in red meat is associated with a reduced risk of colon cancer in people without colitis. Regular exercise also seems to be associated with a reduced risk of colon cancer. These associations may also be true for UC and CD patients but they have not been studied.

1.3 Q: What are the causes of Crohn's disease and ulcerative colitis?

The answer, unfortunately, is that no cause is yet known.

1.4 Q: Could IBD be an inherited condition?

Many researchers believe these diseases may be result of an "inherited predisposition" combined with a triggering environmental agent (possibly a bacteria or a virus). There is no simple, predictable pattern of inheritance though there is certainly some evidence to suggest that heredity has some role to play. For example, when two immediate family members both have IBD, the most common combination is mother-child, followed by sibling-sibling, with father-child being least common.  About 15 to 20% of people with IBD have immediate family members with IBD.

Heredity factors seem to be more important in CD than UC.

1.5 Q: Who gets these diseases?

Up to 2,000,000 Americans are estimated to suffer from IBD with males and females affected equally.

The diseases can appear at any age, but the age at which patients are usually first diagnosed falls neatly onto a bell curve centered at about 24 years old, falling off quickly in the late teens and early thirties.  However, there are also a significant number of patients in whom the diseases first occur in later life.

There are significantly more cases in western Europe and North America than in other parts of the world.

1.6 Q: Are there any factors that predispose to the development of UC and/or CD?

Smoking appears to enhance the likelihood of developing CD.

1.7 Q:  Are there any factors that protect against the development of UC and/or CD?

Smoking appears to protect against the development of UC.

There is data that surprisingly few UC patients have had their appendix removed (appendectomy). This suggests that removal of the appendix may protect against the subsequent development of UC. There is no apparent relationship between appendectomy and CD.

Recommended Books:
Listen To Your Gut : Natural Healing and Dealing with Inflammatory Bowel Disease by Jini Patel Thompson
The IBD Remission Diet by Jini Patel Thompson
Positive Options for Living with Your Ostomy: Self-Help and Treatment by Craig A. White
Coping with Crohn's Disease: Manage Your Physical Symptoms and Overcome the Emotional Challenges by Amy B. Trachter

Continue with Part 2 of 3

Source:  Copyright 1997 by Kevin Horgan, M.D., Christopher Holmes and Michael Bloom.   All rights reserved.   This document, or any derivative works thereof, may not be sold or redistributed for profit in any way without express (not email) written permission of the authors.  This includes, but is not limited to, translations into foreign languages, mass archival as on a CD_ROM and inclusion in commercially published compilations (books).   You are free to copy this list for personal use, or to make it available for redistribution in its electronic format, provided that:  (1) it remains wholly unedited and unmodified, (2) no fee or compensation is charged for copies of or access to this list, and (3) this copyright notice and the following disclaimer remain attached.