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CHAPTER 1

What Is This Disease?

CASE STUDY Kelly

Kelly, a 22-year-old university student, developed symptoms of abdominal cramping, urgency to move her bowels, diarrhea, and blood in the stool. The symptoms came on gradually and were at first intermittent. They began during the month before her first-term exams, and, although they seemed to improve after she finished the exams, the symptoms continued into the second term. She went to the university health clinic, where she was examined and referred to a specialist. The specialist carried out some tests and told Kelly that she had inflammatory bowel disease, specifically, ulcerative colitis.

Kelly was really upset — ulcerative colitis sounded like a serious disease. Besides, the doctor told her there is no cure, other than surgery. It wasn’t fair. “I’m young,” she protested, “and no one in my family has had this disease. I’ve always been very health conscious… I eat a healthy diet, including milk and dairy products. I’m physically active and I don’t smoke.” She couldn’t stop asking questions in her effort to understand why. “What is inflammatory bowel disease? Is colitis an infection? Can I take antibiotics to cure it? Did the stress of my exams cause it? What if I eat a different diet? Could the ibuprofen I take for headaches have an impact?”

Her doctor calmed her down and began answering Kelly’s questions…

(continued)

What Is Inflammatory Bowel Disease?

Inflammatory bowel disease is not a single disease or medical condition. The term describes, in a general way, any condition or disease that results in inflammation of the gastrointestinal tract. Strictly speaking, this definition would include infections of the intestine — for example, infection caused by salmonella bacteria. However, the term “inflammatory bowel disease” (IBD) is usually reserved for two similar disorders, Crohn’s disease and ulcerative colitis. Specific causes for these disorders are not yet entirely known.

Inflammation Location

In Crohn’s disease, inflammation occurs most often in the lower part of the small intestine, called the ileum, and the large intestine, also known as the colon. Crohn’s disease can also affect the esophagus, stomach, and upper parts of the small intestine (duodenum and jejunum).

Crohn’s Disease

Crohn’s disease probably dates back to the early 19th century, based on descriptions of cases of similar ailments in the medical literature of that era. In 1932, Drs. Crohn, Ginzburg, and Oppenheimer at the Mount Sinai Hospital in New York first described the condition as a specific disease entity. The form of the disease they originally described focused on inflammation of the ileum, the last part of the small intestine. They called the condition regional ileitis, with “ileitis” indicating inflammation of the ileum. Several years after Dr. Crohn and colleagues described the condition, it was given the name Crohn’s disease. In the early 1950s, it was recognized that Crohn’s disease did not necessarily affect just the ileum, but that other parts of the gastrointestinal tract, such as the colon or large intestine, could be affected.

Ulcerative Colitis

Like Crohn’s disease, ulcerative colitis had probably been with us for some time before it was fully described in the late 19th century. Ulcerative colitis is sometimes referred to as ulcerative proctitis, ulcerative proctosigmoiditis, or ulcerative pancolitis. These names relate primarily to the extent of the inflammation of the colon rather than to any fundamental differences in the presumed causes of ulcerative colitis. In the first half of the 20th century, the treatment of ulcerative colitis was surgical, and many patients ended up dying of complications of the disease or the surgery. Since the 1940s, there has been a consistent improvement in the surgical and medical management of ulcerative colitis, and death due to complications of the disease or its treatment is now exceedingly rare.

Limited Inflammation

In ulcerative colitis, the inflammation is limited to the large intestine, which includes the rectum. The rest of the gastrointestinal tract is not involved.

Irritable Bowel Syndrome

Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are often confused since their names are so alike. IBS is a poorly understood condition of the gastrointestinal tract. Although IBS is characterized by chronic abdominal discomfort or pain and an alteration in the normal bowel habit, it is quite a different condition from Crohn’s disease and ulcerative colitis (IBD).

In IBS, it is thought that the problems arise from a change in the way the bowel functions or the way in which the brain senses the bowel functioning. In IBS, there has been no clear or consistent evidence that inflammation plays a role in causing the symptoms in humans. This is different from IBD, where inflammation is the main defining characteristic of the disease, and where treatment against inflammation will help treat the disease and alleviate its symptoms. In IBS, treatment is usually aimed at modifying the motility of the gastrointestinal tract or the transmission of the pain impulses from the intestine to the brain.

Glossary of Inflammatory Bowel Disease

Gastroenterologists use several technical terms to describe IBD. You can start to use the language of this disease in discussions with your health-care providers. These terms are defined more thoroughly in their context later in the book.

Abscess: a localized collection of dead and infected tissue (pus), which typically becomes liquid. The consequences may be serious if it is not quickly and properly managed; management involves draining the infected material and treating with antibiotics.

Absorption: the digestive process of extracting nutrients from food and transferring these nutrients into the circulatory system; for example, the absorption of vitamin B₁₂ occurs in the ileum (the last section of the small intestine), which is often problematic in IBD.

Anal sphincter: a muscular valve at the bottom of the rectum, which normally prevents stool from coming out when it is not supposed to. Damage to the sphincter or the nerves supplying the sphincter can lead to fecal incontinence.

Colon (large intestine): the lower part of the gastrointestinal tract, which is primarily responsible for reabsorbing fluid and electrolytes (salts) from the stool.

Colonoscopy: a diagnostic procedure for IBD that involves inserting a scope through the anus and rectum to the colon, where a tissue biopsy may be taken for testing.

Distension: a significant increase in the size of the abdomen that may be due to gas, stool, or fluid.

Duodenum: the first part of the small intestine, which receives ingested food after it has left the stomach. Although the duodenum is relatively short (about 12 inches/30 cm in length), it has an important role in the absorption of some nutrients, particularly iron; it is also the location where digestive enzymes from the pancreas and bile salts from the liver are first mixed together with food in order to help the digestion process.

Enzyme: a protein that helps the rate of a chemical reaction, usually related to an important metabolic function of the body.

Fecal incontinence: loss of the ability to hold stool (fecal waste). This may happen when there is inflammation of the rectum or lower part of the colon, or when there has been damage to the anal sphincter.

Fistula: an abnormal communication or channel from the intestine to other organs or to the abdominal wall or skin.

Gastroenterology: a medical specialty involved in the study of the digestive system, digestive disease, and digestive health.

Gastrointestinal (GI) tract: the tract that extends from the mouth to the anus.

Granuloma: a distinctive collection of inflammatory or immune cells that occurs in tissues affected by certain conditions, including Crohn’s disease.

Ileum: the last part of the small intestine; it makes up about one-third of the entire length of the small intestine. Vitamin B₁₂ is absorbed here.

Inflammatory bowel disease (IBD): any condition or disease that results in inflammation of the gastrointestinal tract, most commonly in the small and large intestine and the rectum.

Irritable bowel syndrome (IBS): a functional GI syndrome characterized by symptoms of abdominal pain or discomfort, along with a change in the bowel habit. There is no inflammation of the GI tract.

Jejunum: the second part of the small intestine, which makes up about two-thirds of the entire length of the small intestine and is responsible for the absorption of most of the nutrients from food.

Lymphocyte: a type of white blood cell that is important in immune protection against a number of different possible bacteria and viruses that can cause infection.

Motility: the movement of food through the GI tract.

Mucosa: the inner lining of the gastrointestinal tract. The integrity of the mucosa is important for carrying out many of the roles of the gastrointestinal tract, particularly digestion of food and absorption of nutrients.

Pancolitis: inflammation that involves the entire colon.

Perforation: a hole in the wall of the intestine, which allows intestinal contents, often with numerous bacteria, into the abdominal cavity, where serious infection may result.

Peristalsis: the involuntary contractions that move food through the GI tract.

Proctitis: a form of colitis that affects only the rectum.

Proteins: compounds made up of long chains of amino acids. Proteins are responsible for many critical functions, including maintenance of bodily structure and metabolic functions.

Rectum: the very last part of the colon (large intestine), where stool is held before it is expelled. Inflammation of the rectum can result in difficulty holding stool for extended periods of time.

Serosa: the outer lining (membrane) that covers the intestine.

Stricture: a narrowing of the central channel in a segment of the intestine, which can lead to obstruction or blockage.

Ulcer: an area in the gastrointestinal tract where there is a loss of the normal internal lining (mucosa). Ulcers can result in complications, such as bleeding or abscesses.

Villi: fingerlike projections of the inner lining of the small intestine (mucosa), which have the effect of increasing the amount of mucosal surface available for absorption of nutrients.

Smoking Paradox

Smoking increases the risk of developing Crohn’s disease, and in those already affected, smoking may make the disease more aggressive or severe. In contrast, smoking seems to protect against ulcerative colitis. Patients with ulcerative colitis are more likely to be nonsmokers or former smokers than a similar group of people selected from the general population. In former smokers, the period soon after smoking cessation seems to be a time of particularly increased risk of developing ulcerative colitis. This observation has led some researchers to use nicotine, in the form of skin patches, as a treatment for ulcerative colitis. Despite the strong association between cigarette smoking and protection against ulcerative colitis, this approach to treatment has not been consistently effective.

Who Gets Inflammatory Bowel Disease?

The onset of inflammatory bowel disease may be influenced by age, gender, and geography.

Age Factors

Crohn’s disease and ulcerative colitis most commonly begin in young people. Although it is unusual to see this disorder in children below the age of 5, there is an increase in the occurrence of IBD up until the age of 20, with maximum incidence in the age group between 20 and 40. It is less common, but certainly not unheard of, for older individuals in their 50s and 60s to first experience IBD. The first onset of disease is quite rare in the elderly. When symptoms first occur in someone from that age group, the attending doctor will usually consider other conditions or illnesses as more likely than IBD.

Gender

Inflammatory bowel disease appears to occur in males and females at roughly the same rate, although some studies have suggested that there may be slightly higher incidence in females. These differences may vary depending on the age of the first onset of IBD, but even if such differences exist, they are likely to be minor and of no major significance.

Population Studies

Although they are generally thought to be diseases that are found more frequently in developed countries, Crohn’s disease and ulcerative colitis have been observed in every race and in every country that has been specifically studied. There do appear to be some interesting differences between countries, as well as between ethnic groups within a given country.

These diseases are much less common in Asia, but this may be changing. In Japan, for example, Crohn’s disease was almost unheard of over half a century ago, but there appears to have been a steady increase in the incidence since then. The incidence in the Jewish population is among the highest of any ethnic or racial group. However, within the Jewish population, there appears to be a difference in incidence depending upon the country of origin. In one study, the incidence of IBD was higher in Jews of Ashkenazi (European) descent than in Jewish populations of Sephardic (Northern African and Middle Eastern) descent.

The varying risks of IBD in different countries are not entirely due to purely inherited or genetic reasons. The increasing incidence of Crohn’s disease observed in Japan suggests that environmental factors have an important effect on the risk of developing IBD. In addition, studies of South Asian immigrants to North America have shown that the individuals who immigrate keep the lower risk of IBD that is seen in their country of origin, whereas their children, who are generally born and raised in North America, have a higher risk of developing IBD in their lifetime. These variations in the incidence of IBD provide clues as to the possible contributing factors or causes and have led to a number of interesting theories and questions that are undergoing further testing.

North-South Gradient

The incidence of IBD has generally been highest in North America and Northern European countries and lower in the countries at more southerly latitudes. This has been described as a “north-south gradient.” However, this gradient is not unique to the north-south comparison but probably reflects an underlying gradient between developed and developing countries.

Where in the Body Does IBD Occur?

Inflammatory bowel disease occurs in specific sections of the gastrointestinal tract, or gut. Before considering what has gone wrong in Crohn’s disease and ulcerative colitis, we need to understand how a healthy gut works. The normal functioning of the intestinal immune system may go awry in inflammatory bowel disease.

Critical for Life

The gastrointestinal tract serves several critical functions that help to keep us alive. It allows nutrients, water, minerals, and vitamins to enter our body while keeping out harmful substances.

Functions of the Gastrointestinal Tract

The gastrointestinal tract is a tubular structure that extends from the mouth all the way down to the anus. The gut has two vital functions — nutrient absorption and immune protection.

Principal Parts of the Gastrointestinal Tract

Nutrient Absorption

The primary job of the gut is to take in and absorb nutrients. These nutrients provide the building blocks and fuel needed to maintain all other bodily functions. The gut absorbs water, minerals, and vitamins from the food and drinks that are ingested.

Immune Protection

At the same time that it allows or promotes absorption of nutrients, the gastrointestinal tract must keep numerous potentially harmful items out of the body. These include microscopic organisms, such as bacteria, viruses, and parasites, as well as certain dangerous proteins that may cause disease if absorbed into the body from the gut. The gastrointestinal tract is, therefore, an important part of the body’s immune system.

Principal Parts of the Gastrointestinal Tract

The gastrointestinal tract has six major components: mouth, esophagus, stomach, small intestine, large intestine, and anus. These may all be affected by inflammatory bowel disease.

Mouth

The mouth and the structures within it (lips, teeth, tongue, and palate) are involved in the ingestion of food. The teeth allow the grinding of food into small particles that are more easily broken down and digested by the enzymes present farther down in the intestine. The lips, tongue, and palate assist with the chewing and swallowing of food.

Esophagus

The esophagus (or gullet) is a tube that transports food, once it is swallowed, from the mouth to the stomach. A valve at the bottom of the esophagus prevents food and stomach acid from coming back up into the esophagus and into the mouth, where it can cause heartburn, which can result in damage to the inner lining of the esophagus. When you vomit, this valve opens up to allow acid and food to come out, and when you burp, it opens to allow gas to come out.

IBD Ulcers

An area that has lost its mucosal lining is called an ulcer. When people talk about ulcers, they are usually referring to duodenal or gastric (stomach) ulcers, which are typically different from the ulcers that may occur in inflammatory bowel disease. In Crohn’s disease and ulcerative colitis, the ulcers usually occur in the small intestine and large intestine and much less commonly in the stomach and duodenum.

Stomach

This saclike structure lies in the upper part of the abdomen. It receives and holds food that has recently been eaten and slowly pushes it down into the small intestine, where most of the absorption of nutrients occurs. There is a valve at the lower end of the stomach that helps to regulate how quickly the food leaves the stomach to enter the small intestine. The stomach provides an important signal to the brain to indicate when you have eaten enough.

The stomach also secretes acid from its lining. This helps to protect against infections caused by harmful bacteria that might inadvertently be ingested during a meal. The stomach acid also helps with the initial digestion of proteins in food. An enzyme called pepsin, also produced by the stomach, provides additional help with breaking down proteins.

Small Intestine

The small intestine (or small bowel) is a tubular structure approximately 12 to 15 feet (4 to 5 m) long. It is divided into three segments: from top to bottom, these are the duodenum, the jejunum, and the ileum. In the small intestine, most of the nutrients in food are absorbed into the body.

Mucosa

The absorption of nutrients is dependent upon the presence of a highly specialized inner lining (or mucosa). The mucosa lining is made up of cells whose main reason for being is to absorb nutrients from the inside (or lumen) of the intestine and pass them through into the body, where they are available as building blocks or fuel for other body functions. The surface of the mucosa is folded into many tiny fingerlike projections, called villi, which effectively increase the surface area and, therefore, the number of cells available for absorption of nutrients.

The surface of these cells contains enzymes that help break down food into smaller components so as to be absorbed more easily. When the intestine is inflamed, as is the case in inflammatory bowel disease, the villi may be reduced in number or size — or may be wiped out altogether so that the inner lining of the intestine appears flat. This loss of normal villi results in a reduced ability to absorb nutrients. When the inflammation is severe, the mucosa lining may be completely gone, leaving the underlying tissue exposed to the inside of the intestine.

Large Intestine

The large intestine, also known as the colon, is approximately 3 to 4 feet (1 to 1.2 m) in length. Although shorter than the small intestine, it is called the large intestine because its width or diameter is greater than that of the small intestine. It is divided into several sections: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum.

Primary Function

The large intestine’s primary function is to absorb fluid (water) and minerals, such as sodium and potassium, from the intestinal contents back into the tissues and into the bloodstream. By absorbing fluid, the colon causes the stool to be solid rather than liquid and helps to prevent fluid loss and dehydration.

Small Intestine

Rectum

The last part of the large intestine is called the rectum. The wall of the rectum can stretch, up to a certain point, to allow stool to be kept inside until there is an appropriate time to evacuate. When the rectum is inflamed or somehow diseased in other ways, that ability to hold stool is reduced, and you may feel the need to go to the bathroom very frequently and urgently. In some instances, this can result in accidents with associated loss of control of bowel function, otherwise known as fecal incontinence. This need for frequent bathroom visits and the urgency that may go along with it can be one of the most troubling symptoms of inflammatory bowel disease.

Related Parts of the Gastrointestinal Tract

There are other parts of the gastrointestinal tract involved to a greater or lesser extent in digestion and nutrient absorption. These organs, which are typically connected to the tubular part of the gastrointestinal tract by small channels (or ducts), include the liver, gallbladder, and pancreas. The gallbladder and pancreas are usually not affected by inflammatory bowel disease. However, the liver may be affected in a small proportion of patients. Occasionally, this can lead to liver damage.

Liver

The liver has many functions, but the one that is most involved in digestion is bile production. Bile is similar to a detergent, in that it allows fat to be broken down and made into a form that can be dissolved or mixed with water. Normally, fat remains separate from water, like the fat floating on the top of chicken soup. This ability of bile to break up fat into small particles and disperse those particles in the watery contents of the small intestine is crucial to fat digestion and absorption.

Gallbladder

Bile that is produced by the liver is usually stored in the gallbladder, a small sac next to the liver, until it is needed after a meal. When the production of bile is not adequate or if bile is blocked from reaching the intestine, absorption of fat from the diet is reduced. As a result, fat may end up coming out in the stool. This appears as droplets of fat or oil in the stool.

Pancreas

The pancreas is a gland producing a number of digestive enzymes that enter the upper part of the small intestine. The pancreas lies very close to the duodenum and has a small duct running through it that carries the enzymes from the pancreas into the duodenum. These enzymes help break down protein, starch, and fat in the diet into components that can be easily absorbed by the intestine.

Anus

The anus (or anal canal) is the passageway that stool follows when it leaves the body. The primary role of the anus is to keep the stool that is present in the rectum from coming out when you don’t want it to come out. In other words, it helps to prevent fecal incontinence. Within the anal canal, there are two main muscular anal sphincters (or valves) that help to prevent the stool from coming out involuntarily.

One of the sphincters, called the external anal sphincter, is under your conscious control. In other words, you can control or tighten this particular sphincter when trying to hold in stool or gas. The other sphincter, the internal anal sphincter, is not under voluntary control, but works reflexively at a subconscious level. Maintaining continence and ensuring the smooth and complete emptying of the rectum requires the coordination of the two anal sphincters. If either of these two sphincters is damaged or diseased, it can result in fecal incontinence.

Signs of Inflammation

Inflammation occurs in response to any sort of injury, whether it is from a serious or life-threatening infection or from something as small as a paper cut. The classic signs of inflammation are pain, swelling, redness, and loss of normal function.

What Goes Wrong in IBD?

Crohn’s disease and ulcerative colitis involve inflammation of the gut. A healthy person normally has a certain degree of inflammation in the gastrointestinal tract, but in those with IBD, the inflammation is extensive and excessive.

Excessive Inflammation

Excessive or uncontrolled inflammation is central to the onset of Crohn’s disease and ulcerative colitis. As scientists learn more about the factors that control the degree of inflammation in the gut, they learn more about the causes of these disorders.

Normal Intestinal Inflammation

In the gut, the degree of inflammation that is normally present in healthy people is usually not enough to cause loss of function or to be seen by the naked eye, but when viewed under the magnification provided by a microscope, you can always see some white blood cells, called lymphocytes, present within the inner lining and just beneath the lining of the intestine.

These defensive cells are part of the intestine’s immune system and help to protect you from potentially harmful bacteria, viruses, parasites, and proteins that aren’t normally present in the body. The amount of inflammation is closely regulated so that there is just enough immune response so as to protect against these dangers, but not so much that it will cause problems.

Too much of a good thing may be bad, and the amount of inflammation in the intestinal lining is no exception. If there is too much inflammation or if it is not properly controlled, inflammation can cause swelling and damage to the tissues of the gastrointestinal tract. This damage can lead to problems with the normal functioning of the gastrointestinal tract, including absorption of nutrients and fluids and retaining and expelling stool at appropriate times.

When the damage is particularly severe, the internal lining of the gastrointestinal tract can slough off, leading to a variety of symptoms, such as abdominal pain, diarrhea, blood in the stool, weight loss, and failure of children to grow properly.

Ulcerative Colitis Signs

Inflammation in ulcerative colitis is limited to the colon, but the extent of the inflammation within the colon varies from person to person and may vary within an individual over the course of the illness.

Any portion of the colon may be inflamed in ulcerative colitis, leaving the remainder completely unaffected. However, the rectum is always inflamed or diseased.

Pancolitis

In many instances, the entire colon is inflamed. This is referred to as pancolitis. When the inflammation extends upward, it does so in a continuous fashion. In other words, there are no areas of inflammation separated from one another by normal areas of colon.

Proctitis

In some people with ulcerative colitis, only the rectum is inflamed. This particular form of the disease is often referred to as proctitis or ulcerative proctitis. Some differences have been observed between proctitis and the more extensive forms of the disease, such as pancolitis. Ulcerative proctitis is unusual in children and tends to be seen more often when the disease occurs for the first time in middle-aged or elderly individuals.

Limited Extent

Because the extent of inflammation in ulcerative proctitis is so limited — involving at most just the last 6 inches (15 cm) of the large intestine — patients suffering from that form of the disease are usually not as sick as patients with more extensive forms of ulcerative colitis.

Crohn’s Disease Signs

In Crohn’s disease, the inflammation can occur in any part of the gastrointestinal tract. Although it appears most often in the ileum and colon, Crohn’s disease can affect the esophagus, stomach, duodenum, and jejunum.

Skip Lesions

The areas of the gut affected by Crohn’s disease may not be adjacent to one another. These are called skip lesions. For example, someone with Crohn’s disease may have an area of inflammation in the middle part of the small intestine (jejunum) and another area of inflammation in the large intestine, with normal intestine in between the two areas of inflammation.

Intestinal Penetration

In ulcerative colitis, the inflammation tends to be limited to the innermost lining of the gut, but in Crohn’s disease, the inflammation has a tendency to penetrate from the innermost lining, where inflammation and ulcers first occur, right through the deeper layers of the bowel to the outer surface (serosa). This results in a defect or hole in the bowel wall, which can lead to localized infections in the abdominal cavity (abscesses) or communications (fistulas) from the bowel into other organs or into the abdominal wall or skin. The inflammation in Crohn’s disease may also form into tiny localized collections of inflammatory cells, called granulomas, which can be seen only under the magnification provided by a microscope. These granulomas are virtually diagnostic of Crohn’s disease.

Site Variation

The wide variation in the sites of the gut that are affected by Crohn’s disease can lead to important differences in the ways individual patients experience the disease and the ways in which they come to medical attention. This variation in sites also affects approaches to management of the disease.

Indeterminate Colitis Signs

In a small proportion of individuals with inflammatory bowel disease involving the colon, it is not possible, based on the disease features, to differentiate between ulcerative colitis and Crohn’s disease. In these instances, the condition is designated as indeterminate colitis or inflammatory bowel disease of undetermined type (IBDU). In some cases of indeterminate colitis, the pattern of disease will change over time, and it will become apparent that the patient, in fact, has ulcerative colitis or Crohn’s disease. However, some patients will continue to have features of both ulcerative colitis and Crohn’s disease, and distinguishing between the two will not be possible.

The approach to the management of the two conditions with medications is similar. Differentiation becomes much more important if surgery is contemplated as a means of treatment, as the surgical approaches in ulcerative colitis and Crohn’s disease can be quite different because of the fact that Crohn’s disease can come back after surgery in parts of the bowel that weren’t affected before surgery.

What Are the Possible Complications of IBD?

Complications Specific to Crohn’s Disease

•Strictures

•Abscesses

•Fistulas

There are several serious complications that can occur as a result of having inflammatory bowel disease. This is where the danger lies. Some complications are common to Crohn’s disease and ulcerative colitis, whereas others are unique to one form of IBD or the other. Generally, the complications can be divided into those that occur directly from the inflammation or ulceration that occurs in the intestine and those that occur in areas of the body that are not directly connected to the intestine or directly related to the intestinal inflammation.

Crohn’s Disease Complications: Strictures, Abscesses, and Fistulas

Inflammation and Ulceration Complications

Inflammation and ulcerations can lead to strictures, fistulas, and abscesses in the gut. If these complications are not properly managed, they can, in turn, lead to further tissue damage and uncontrolled infection. Death can occur if this happens. While these complications are often seen in Crohn’s disease, they are very rare in ulcerative colitis.

What are strictures?

Strictures are segments of the intestine in which the normally large internal opening becomes narrowed. This can be due to the swelling that occurs in the tissues of the intestinal wall as a result of active inflammation, similar to the swelling you get when you experience an injury, such as a broken bone. More often, the stricture is due to scarring of the intestinal tissues following repeated or ongoing episodes of inflammation and healing.

Strictures

Strictures are not necessarily a problem until they cause a bowel obstruction, commonly referred to as a blockage. Food or other material becomes caught in the narrowed stricture, preventing anything else from passing through. This produces back pressure in the intestine “upstream” from the stricture, causing sharp, often crampy pain, a distended abdomen, and nausea and vomiting. Sometimes there may be warning signs that a stricture may be worsening or leading to an obstruction. These signs include frequent or recurrent pain in the center of the abdomen after eating, along with a feeling of distension or bloating of the abdomen.

Foods to Avoid When You Have an Intestinal Stricture

•Popcorn

•Nuts

•Seeds

•Corn

•Raw vegetables

•Skins on fruits

Bowel Obstruction

Not everyone with a stricture develops intestinal obstruction. If you experience a bowel obstruction that is not severe and know the symptoms, you can sometimes manage it on your own by avoiding solid food and drinking only fluids for several hours or even a few days. If you have a stricture, it is important that you avoid eating foods that aren’t easily digested and that, as a result, may get lodged in the narrowed part of the intestine. These foods include popcorn, nuts, seeds, corn, raw vegetables (particularly stringy ones like celery), and skins on fruits.

This complication can be an emergency situation. You will usually require monitoring in a hospital setting, with intravenous fluids given to prevent dehydration and possibly the insertion of a nasogastric tube (a plastic tube inserted through the nose and down the esophagus into the stomach) to take fluid and gas out of the stomach.

Bowel Obstruction Symptoms

•Severe crampy pain, usually centered in the middle of the abdomen

•Distension or bloating of the abdomen

•Reduced number of bowel motions

•Not passing gas

•Nausea and vomiting

Not all symptoms are necessarily present when a bowel obstruction has occurred, particularly if it is partial or incomplete.

If the obstruction does not settle with these measures, then surgery is usually required to remove the strictured area of bowel. Fortunately, most obstructions that are due to Crohn’s disease strictures settle without the immediate need for surgery, but repeated obstructions usually mean that surgery is required. In that instance, the surgery can be scheduled electively so that it is performed when you are well nourished, not sick, and not on medications that might affect healing and recovery after surgery. Medications are not very effective at relieving obstruction, particularly when the narrowing is due to scarring.

Immediate Medical Attention

If there is fever with the stricture symptoms, if there is frequent vomiting, or if after 6 to 8 hours symptoms of the obstruction are not starting to clear, as evidenced by reduced pain, decreased abdominal distension, and resumption of normal bowel motions and passing gas, then immediate medical attention is needed.

Abscesses

When a deep ulcer penetrates through all of the layers of the intestine, the contents of the intestine, primarily bacteria and fecal material, can leak out and into the abdominal cavity and tissues around the intestine. When a lot of this material leaks out suddenly, it can produce a serious, and occasionally fatal, infection called peritonitis.

In Crohn’s disease, this leakage normally occurs very gradually, and the tissues around the intestine have a chance to react and to form a barrier against free leakage of the bacteria into the abdominal cavity. As a result, the bacteria accumulate in a localized area that is effectively walled off. The bacteria grow in the center of this walled-off region, causing a localized infection known as an abscess. An abscess typically contains pus in its center.

Serious Bacterial Infection

When an abscess is not properly treated, it can grow in size. Eventually, the bacteria can spread into the bloodstream and throughout the body, or it can burst into adjacent organs and tissues or into the abdominal cavity, causing the pus to spread throughout the abdomen. Any of these situations can be extremely serious or life threatening.

Fistulas

Fistulas are abnormal channels or tracts joining one part of the intestine to another part of the intestine or to another organ. When an area of the intestine becomes inflamed and ulcerated, the ulcer can penetrate through the full thickness of the intestine wall into an adjacent tissue. This is promoted by the fact that inflamed intestine tends to be “sticky” on its outside surface and will attach to other adjacent segments of intestine, to surrounding organs, or to the inner surface of the abdominal wall.

When a fistula forms between two segments of intestine, there may be no obvious bad consequences, but it is possible that the fistula can result in ingested food bypassing large segments of the intestine. This can cause decreased absorption of nutrients, leading to weight loss and malnutrition. Fistulas can pass from the intestines to adjacent organs, such as the bladder, which, in turn, leads to recurrent urinary infections.

Perianal Fistulas

The most common type of fistula occurs in the area around the anus. These anal fistulas are thought to arise from an infection or inflammation in the glands just below the lining of the anal opening. The infection or inflammation can burrow in various directions through the surrounding tissues and eventually open onto the skin in the area outside the anus. These types of fistulas, also called perianal fistulas or perineal fistulas, can be extremely distressing, and, for some individuals, dominate all other manifestations of their Crohn’s disease.

People with perianal fistulas can have ongoing episodes of pain around the area of the anus, along with swelling and drainage of mucus, pus, blood, and stool. In women, the inflammation and fistulas can extend from the area around the anus to the area of the vagina. When they are particularly severe, the symptoms related to fistulas can interfere with everyday activities, such as sitting, walking, exercising, and riding a bike.

Pain and Shame

When a fistula goes from the intestine to the skin of the abdominal wall or around the anus, intestinal fluid or stool comes out through the opening of the fistula on the skin. In addition to being unsightly, this intestinal fluid makes it difficult to keep the area clean and can be irritating to the surrounding skin.

Because of the location of some fistulas, they can also get in the way of some types of sexual activity. This is not simply a result of the pain that may be associated with a fistula, but also of the potential embarrassment or shame of being “unclean.” If you have these feelings, it is important to realize that you are not alone. Discussing your concerns with your partner will often help soothe some of your fears and concerns about being intimate. Together, you may even be able to come up with sexual activities or positions that you both find pleasurable and that you will not find painful or uncomfortable.

Extra-Intestinal Manifestations

Both Crohn’s disease and ulcerative colitis may be associated with inflammation of tissues outside of the intestinal tract, specifically the joints, eyes, skin, and liver. The extra-intestinal manifestations often occur when the intestinal disease is more active or symptomatic, but they can also occur when the bowels are not giving any trouble at all. Unfortunately, there is no good way to predict who might get these particular complications, nor do we know how to prevent them from occurring. We do know that certain complications have some genetic or inherited basis contributing to their occurrence in IBD.

Complications of IBD Outside the Intestine (Extra-Intestinal Manifestations)

•Joint symptoms (pain, stiffness, swelling)

•Sacroiliitis

•Eye inflammation

•Skin lesions

•Liver disease (primary sclerosing cholangitis)

•Bone disease

Joint Inflammation

Joint symptoms are probably the most common extra-intestinal manifestation of IBD, occurring in up to 30% of patients. The joints that are most commonly affected are the knees, ankles, wrists, and small joints in the fingers (knuckles) and toes. Symptoms of joint involvement or inflammation include pain and stiffness in the joints or, when severe, swelling and redness.

Sacroiliitis

A specific type of arthritis, called sacroiliitis, can occur in the lower back of patients in both Crohn’s disease and ulcerative colitis. This typically presents first with stiffness in the lower back in the mornings and a vague discomfort over the lower back or hips. In a more severe form, called ankylosing spondylitis, the inflammation can extend up the spine, ultimately causing the bones of the spine to fuse together, thereby reducing flexibility and mobility. For ankylosing spondylitis, there is a blood test that can predict who is at risk for developing it, but unfortunately there is really no way to prevent its development.

Compounded Problems

Unfortunately, some of these joint problems, particularly sacroiliitis, tend to persist even when the underlying bowel disease is adequately treated and controlled. To compound the problem, some of the drugs commonly used to treat joint inflammation, such as nonsteroidal anti-inflammatory drugs, may be harmful to the intestinal tract of patients with IBD.

Eye Inflammation

Eye inflammation is a relatively uncommon, but potentially serious, occurrence in IBD. There are several different, though closely related, forms of eye inflammation that can occur (called iritis, uveitis, and episcleritis), which all lead to red and often painful eyes. In some instances, the pain is made worse by bright lights, and there may also be blurring of vision. Any of these symptoms should be assessed promptly by a doctor and treatment started. The usual treatment is medicated eye drops containing steroids, but these should be used only after a proper examination by a qualified practitioner.

Skin Lesions

There are two main types of skin lesions that can be seen occasionally, but not frequently, in patients with IBD: erythema nodosum and pyoderma gangrenosum. Although it isn’t known for certain if early treatment of the skin lesions of IBD result in better outcomes, it is important to be aware of any skin lesion that is particularly painful or enlarging for no apparent reason.

A third type of skin lesion, psoriasis, although not directly caused by IBD, can be seen more frequently in IBD, particularly in patients with Crohn’s disease. Psoriasis typically results in red, raised, scaly, and itchy rashes that can occur just about anywhere on the body. What is interesting is that Crohn’s disease and psoriasis share some genetic factors that increase the risk of both conditions, and the drug treatments of the two inflammatory conditions overlap. Some therapies, such as treatments based on the antitumor necrosis factor (infliximab or adalimumab) or on anti-interleukin-12/23 (ustekinumab), may be effective for both.

Enlarging Lesions

•Patients often say that erythema nodosum and pyoderma gangrenosum lesions seem to start with what they thought was a bruise or an insect bite but quickly enlarge and worsen. When this happens, a doctor should be notified promptly.

•The drug infliximab has been shown to be particularly effective at healing pyoderma gangrenosum lesions.

Erythema nodosum

The lesions of erythema nodosum are red or purplish, raised, and painful. They occur most often on the shins. They typically appear when the bowel symptoms are more active and go away as the bowel disease responds to treatment, sometimes leaving a small area of discoloration.

Pyoderma gangrenosum

Pyoderma gangrenosum is an area of ulcerated skin that usually occurs on the legs, but can occur on other areas of the body, particularly near the site of an ileostomy or colostomy. The lesion is sometimes painful, but it often looks much worse than it feels. The ulcerated area can grow to be quite large — sometimes 2 inches (5 cm) or even more across — and fluid can often ooze from its surface. Although it may improve when the bowel disease is treated, it does not always. When the lesions heal, they may leave areas of scarring or changed pigmentation.

Infliximab (Remicade) and adalimumab (Humira), two of the antitumor necrosis factor (anti-TNF) based treatments that are used to treat IBD, can be effective at healing pyoderma gangrenosum lesions.

Skin Rashes

Although treatments based on the antitumor necrosis factor (infliximab, adalimumab, and golimumab) may be effective at treating the skin lesions associated with IBD, their use may also result in unusual skin rashes. These are generally not serious and can usually be managed with creams or ointments applied to the site of the rash. In rare cases, these drugs can be associated with new onset of a skin condition called psoriasis or, in some cases, a worsening of psoriasis that was present prior to the start of therapy. This is an unusual reaction to therapy because these drugs are usually quite effective at treating psoriasis.

Although it isn’t known for certain whether earlier treatment of the skin lesions of IBD results in better outcomes with treatment, it is important to be aware of any skin lesion that is particularly painful, ulcerated, or enlarging for no apparent reason. Patients often say that erythema nodosum and pyoderma gangrenosum lesions seem to start off as what they thought was a bruise or an insect bite but quickly enlarge and worsen. When this happens, see your doctor promptly.

Liver

The most serious liver condition related to IBD is called primary sclerosing cholangitis (PSC). PSC appears to be somewhat more common in ulcerative colitis than in Crohn’s disease, and when it occurs in Crohn’s disease, there is often involvement of the large intestine (colon) with inflammation. PSC is thought to begin as an inflammation that specifically involves the small channels (ducts) carrying bile from the liver to the small intestine. It can lead to scarring and narrowing of these bile ducts, and, when severe or advanced, can result in damage to the liver. If the condition continues to progress, it can lead to liver cirrhosis and liver failure. PSC also predisposes the patient to episodes of bacterial infection of the bile ducts.

PSC Incidence

No more than 5% of people with IBD are affected by the serious liver complication called primary sclerosing cholangitis (PSC). If the condition continues to progress, it can lead to liver cirrhosis and liver failure.

PSC is usually first suspected because of abnormal blood tests. This usually requires further tests or scans to see if the strictures characteristic of PSC are present. Occasionally, a liver biopsy may be necessary to sort out the possible causes. Most doctors will include blood tests of liver function and inflammation as a part of the routine checkup, even for individuals whose IBD is quite stable and not flaring. This may allow for earlier detection of PSC, but there is not an effective therapy that will prevent the progression of PSC to liver cirrhosis.

Fever and Jaundice

In someone who has PSC, any episode of fever, particularly if it occurs with jaundice (yellow color) of the skin or eyes, needs to be assessed and treated immediately.

Mildly abnormal blood tests indicating liver inflammation or irritation are usually temporary and do not indicate any serious damage or long-term consequence to the liver. The abnormal blood tests are probably due to small areas of inflammation within the liver tissue that are a reaction to the associated bowel inflammation. It is not known how or why this occurs, but it tends to go away on its own and can recur repeatedly over time.

PSC is also associated with an increased risk of colorectal cancer. This increased risk requires specialized and intensive monitoring or surveillance with regular colonoscopies. PSC is also associated with an increased risk of bile duct cancer. Unfortunately, there is no good way to monitor for this complication.

Bone Disease

Although bone disease is not, strictly speaking, considered to be an extra-intestinal manifestation of IBD, individuals with IBD are at higher risk of developing certain types of bone disease. In the past, osteomalacia and rickets — serious problems with bone formation — were seen as a result of severe vitamin D deficiency in patients with Crohn’s disease. These conditions are seldom seen now, probably as a result of better medical and nutritional treatments for patients with IBD.

Osteoporosis

Osteoporosis has been recognized as a prevalent condition. Osteoporosis involves a decrease in the density of the bone that occurs as a result of a reduction in the amount of minerals, such as calcium, in the bones. The bones are not strong and, therefore, susceptible to fracture with only minor trauma or sometimes without any apparent reason. Osteoporosis does not produce any symptoms until a fracture occurs.

Minerals and Vitamins

For patients with IBD, maintaining an adequate intake of minerals and vitamins is an important means of preventing osteoporosis — not only good calcium and vitamin D intake but also good overall nutritional intake in terms of total calories and protein in the diet.

While osteoporosis commonly occurs in older individuals without IBD, particularly in women, it seems to occur at an earlier age in patients with IBD. There are several reasons why IBD patients are more susceptible to developing osteoporosis at a younger age. The disease itself, particularly in Crohn’s disease, and the associated inflammation appear to lead to reduced bone density, probably as a result of factors released into the bloodstream from the inflamed tissues. These factors, in turn, interfere with bone formation. Poor intake or absorption of certain key nutrients, such as calcium and vitamin D, may also play an important role in some patients. In addition, a person’s overall nutritional state, as reflected by body weight, is also an important factor in determining bone density. In general, individuals who are underweight or malnourished tend to be more at risk of developing osteoporosis.

Osteoporosis Risk

People with IBD are at increased risk of developing osteoporosis, particularly if they have Crohn’s disease or if they have received steroid medications. Some studies have indicated rates of osteoporosis of 30% in IBD patients. Osteoporosis appears to be more common in Crohn’s disease than ulcerative colitis.

Medications

Medications are a major factor in the development of osteoporosis in IBD patients. In particular, steroid medications, such as prednisone, have been associated with an increased risk. Most doctors try to limit the duration of steroid treatment in their patients with IBD, and when starting someone on steroids, they will often recommend calcium and vitamin D supplements or start the patient on bisphosphonate medications (for example, etidronate, alendronate, zoledronate, and risedronate) that can help prevent further bone density loss. Most other medications used to treat IBD do not affect bone density.

The treatment of low bone density in children and adolescents with IBD is somewhat different than in adults. The period during adolescence and early adult life is critical in determining the health of the skeleton and bones in later life. People reach their maximum bone density in early adulthood. However, adolescents with IBD may not be able to reach their potential maximum bone density because of poor nutritional intake, because of the underlying IBD, or because of medications. Special attention needs to be paid to adequately treating the IBD, to maintaining good nutrition, and to minimizing use of steroids during these critical years.

Bone Density Tests

Most IBD patients, particularly those with Crohn’s disease, should have their bone density measured and, if it is lower than normal, it should be checked periodically (every 1 to 2 years). Bone density is measured using a safe and easy test called a DEXA (dual energy X-ray absorptiometry), which doesn’t require any injections.

Cancer

While people with IBD have an increased risk of cancer, this should not be a cause for undue concern.

Cancer is a common disease that can occur in many forms and degrees of seriousness. The increased risk of cancer in IBD patients appears to be limited to one or — at most — a handful of cancer types. Risk of colorectal cancer (cancer of the rectum or large intestine) appears to be most increased in individuals with IBD.

Some recent research has suggested that patients with more inflammation occurring over a period of many years are at increased risk, but colorectal cancers can also be found in people who have had a very mild IBD course.

While not everyone with IBD is at increased risk of developing colorectal cancer, it is important to be aware of the factors that do seem to increase the risk. For many years, only individuals with ulcerative colitis were considered to have an increased risk of colorectal cancer, but it now appears that people with Crohn’s disease, where the large intestine is extensively affected, are also at increased risk. However, in those individuals with ulcerative colitis, where the disease is limited to the rectum and the last part of the colon, there is no significant increase in the risk of cancer. Patients diagnosed before 20 years of age, with more than an 8-year history of IBD or with associated primary sclerosing cholangitis, are at increased risk of colorectal cancer. The risk appears to increase further the longer one has had the disease. Patients with a family history of colorectal cancer involving a parent, brother, or sister are likely also at increased risk. Whether or not the severity of the IBD affects the cancer risk is not entirely known.

Risk Factors for Colorectal Cancer

•Extensive inflammation of the colon (ulcerative colitis or Crohn’s colitis)

•Early age of diagnosis (less than 20 years of age)

•Long duration of disease (more than 8 years)

•Active disease symptoms

•Family history of colorectal cancer

•Primary sclerosing cholangitis (PSC)

What can I do to reduce my risk of developing colorectal cancer now that I have IBD?

The first thing to do is to determine your degree of risk. This should be done in consultation with your doctor. If it is determined that you are at increased risk, by virtue of the risk factors, then it is possible that your doctor will recommend that you should enter into a screening program. Even if screening is not recommended, regular follow-up with your doctor is important.You may have heard of colorectal cancer screening for individuals who do not have IBD. This is different from the screening that an IBD patient would require. Some of the methods of screening used for non-IBD individuals, such as testing the stool for microscopic traces of blood, are not effective for screening IBD patients. Monitoring for symptoms of cancer is not effective because the symptoms of colorectal cancer may be very similar to those of IBD. The screening that is carried out in IBD patients involves conducting a colonoscopy in order to take numerous random biopsy samples of the colonic lining. Although this type of screening program does appear to reduce cancer rates and result in cancers being detected earlier at curable stages, it is still not a perfect method.In recent years, efforts have been made to detect precancerous changes by using newer colonoscopy technologies so that the areas of potential concern are made visible to the naked eye, allowing biopsies specifically targeted to those areas rather than the random biopsies that have been traditionally performed.

Dysplasia

Biopsies are carefully examined by a pathologist looking for precancerous changes, called dysplasia. If these changes are found, they indicate a higher possibility (10% to 20%) that the patient may already have cancer or, if cancer isn’t already present, the patient has a substantial chance of developing cancer over the subsequent few years. When dysplasia is found and confirmed, surgery to remove the colon is usually recommended.

Colorectal Cancer Risk

It has been estimated that people with ulcerative colitis have a 10% to 15% risk of developing colorectal cancer during their lifetime.

Prevention and Treatment

Because we cannot yet predict with certainty who will suffer from inflammatory bowel disease and because the causes of this disease have not yet been determined conclusively, it is difficult to recommend effective prevention strategies. The best strategy for now is to learn how to recognize the symptoms of the disease and bring them to the attention of your doctor for immediate assessment, diagnosis, and treatment. In the next chapter, we present a discussion of the symptoms of inflammatory bowel disease and the tests used by doctors to diagnose this condition.