A person with Crohn's disease has chronic inflammation within the digestive tract -- most commonly near the end of the small intestine and in the colon. This inflammation usually occurs in patches, with sections of healthy tissue in between. Symptoms of Crohn's disease often include diarrhea and abdominal pain (or stomach pain). While the disease cannot be cured, treatment can help many people with the disease live active lives.
Crohn's disease is a type of "inflammatory bowel disease," or "IBD." There are several different types of IBD, with Crohn's disease and ulcerative colitis being the most common. They all cause chronic inflammation in the digestive tract. The cause of these inflammatory bowel diseases is not known. Researchers estimate that up to 2 million people in the United States have some form of inflammatory bowel disease.
Crohn's disease can affect people of all ages, genders, and ethnicities. While it is often diagnosed between the ages of 15 and 30, it can begin at any age. Caucasians are more often affected than African Americans and Asians. Crohn's disease is also more common in people of Jewish descent. Men and women are equally affected by the disease, and it seems to run in some families. About 20 percent of people with Crohn's disease have a blood relative with some form of IBD, most often a brother or sister.
If you have Crohn's disease, your digestive system still works in the same way to push food along as it is digested. However, the intestines have become irritated and inflamed. This inflammation usually occurs in patches along the digestive tract, with sections of healthy tissue in between.
The inflammation affects more than one layer of the wall of the digestive tract, and it can cause the intestines to empty more frequently -- resulting in diarrhea. The intestines may also be swollen or have sores, which can cause pain as food is moving through.
The inflammation is also chronic, meaning that it lasts for a long time and keeps returning.
Crohn's disease can develop anywhere along the digestive tract, from the inside of the mouth to the anus. But, most commonly, it is found in the ileum (the last part of the small intestine) and/or in the colon. Nearly half of all cases involve both the small and large intestine. About 20 percent of cases are in the colon (large intestine) alone. Lesions near the anus occur in about one-quarter to one-third of people with the disease, but are rarely the only site of Crohn's disease.
When just the end of the small intestine is affected, it's called "ileitis" or "regional enteritis." When both the small intestine and the colon are involved, it's called "ileocolitis." And when only the colon is involved, it's called "Crohn's colitis" or "Crohn's disease of the colon."
The exact cause of Crohn's disease is not known. Some possible causes include genetic problems, certain types of infections, problems with the immune system, and the environment. Stress, anxiety, or the foods you eat do not appear to be causes of the disease. Crohn's disease is not contagious -- you cannot catch it from another person.
Crohn's disease research scientists do not yet know exactly what causes Crohn's disease -- there are only theories about its cause. Some possible causes of Crohn's disease that have been studied include:
genetics
the immune system
previous infection
environmental factors
smoking
It is possible that Crohn's disease is caused by a combination of factors.
While research scientists do not know the exact cause or causes of Crohn's disease, they do not believe that stress, anxiety, or the foods you eat cause the disease.
Crohn's disease is more common in whites and Jews, as well as people who have a family history of Crohn's disease. In fact, studies show that about 1 out of 5 people with Crohn's disease have a close relative with some type of inflammatory bowel disease. Researchers have identified 32 different specific genetic mutations (alterations) that are more common in people with Crohn's disease than in the general population.
There is also evidence that Crohn's disease can run in families. About 3 in 20 people with the condition have a close relative (mother, father, sister or brother) who also has Crohn's disease. If you have an identical twin with Crohn's disease, you have a 70% chance of also developing it.
The fact that Crohn's disease is more common in some ethnic groups than in others also suggests that genetics plays an important role.
Crohn's disease is considered a "complex trait," meaning that several genes at different locations in the genome may contribute to Crohn's disease. A location for the genes that contribute to Crohn's disease susceptibility was recently mapped to chromosome 16. Candidate genes found in this region include several involved in the inflammatory response, such as:
CD19, involved in B-lymphocyte function
Sialophorin, involved in leukocyte adhesion
The CD11 integrin cluster, involved in microbacterial cell adhesion
The interleukin-4 receptor, which is interesting, as interleukin-4-mediated functions are altered in inflammatory bowel diseases (IBDs).
The immune system provides protection against harmful bacteria that could potentially find their way into the digestive system.
The digestive system is also home to more than 500 different types of so-called 'friendly bacteria' that help to digest food. The immune system has to recognize these bacteria and let them do their job without attacking them.
It seems that, in Crohn's disease, something disrupts the immune system, which sends a special antibody, known as tumor necrosis factor (TNF), to kill all bacteria, regardless of whether they are friendly or not. It is the TNF antibodies that cause most of the inflammation associated with Crohn's disease.
In certain genetically susceptible individuals, a previous childhood infection may lead to an abnormal immune response, causing the symptoms of Crohn's disease.
One possible source of this infection is a bacterium called Mycobacterium avium subspecies paratuberculosis (MAP). MAP is commonly found in cows, sheep and goats.
Research has found that people with Crohn's disease are seven times more likely to have traces of MAP in their blood compared with the general population.
MAP has been known to survive the pasteurization process (where milk is treated with heat to kill bacteria), so it is possible that people have become infected with MAP by drinking milk from contaminated animals.
However, the exact role that MAP may play in the development of Crohn's disease is uncertain.
There are two unusual aspects of Crohn's disease that have led many researchers to believe that environmental factors may play a part. These are explained below.
Crohn's disease is a 'disease of the rich'. The highest number of cases occurs in developed parts of the world, such as the UK and US, and the lowest number in developing parts of the world, such as Africa and Asia.
Crohn's disease became much more widespread from the 1950s onwards. Before the Second World War the condition was rare.
This suggests that there is something associated with modern, western lifestyles that increases a person's risk of developing Crohn's disease.
One theory to explain this is known as the hygiene hypothesis. It suggests that as children grow up in increasingly germ-free environments, their immune system does not fully develop due to a lack of exposure to childhood infections. However, there is little in the way of hard, scientific evidence to support this theory.
An alternative theory is the cold-chain hypothesis, which suggests that the increase in the number of cases of Crohn's disease might be linked to the increased use of refrigerators after the Second World War.
Psychrotrophic bacteria are bacteria that can survive, and sometimes grow, in cold environments. The cold-chain hypothesis theorizes that, as people eat more chilled foods, their exposure to these bacteria increases and it is this that causes the abnormal immune response.
Traces of psychrotrophic bacteria have been found in people with Crohn's disease, although, as the researchers behind the cold-chain hypothesis admit, this could be pure coincidence.
Aside from family history and ethnic background, smoking is the most important risk factor for Crohn's disease. Smokers are twice as likely to develop Crohn's disease compared with non-smokers.
Furthermore, people with Crohn's disease who smoke usually experience more severe symptoms compared with those with the condition who do not smoke.
In people with Crohn's disease, symptoms usually include abdominal pain and chronic diarrhea. Several other signs and symptoms are possible, such as weight loss, rectal bleeding, and vomiting. Some symptoms of Crohn's disease, such as abdominal swelling, fever, and bowel movements that contain only blood clots, can be signs of a flare-up or complications that may require immediate medical attention.
Crohn's disease is a type of inflammatory bowel disease (IBD) that can affect the small intestine, colon, or both. For a person with Crohn's disease, symptoms will depend on which part of the digestive tract is affected. For example, the most common symptoms of Crohn's disease that affects the colon are diarrhea and pain. When it affects the small intestine, symptoms often include fatigue, weight loss, and abdominal discomfort on the right side. Diarrhea is less common with Crohn's disease that only affects the small intestine.
Symptoms will also depend on the severity of the disease. Some people have a mild case of Crohn's disease and have symptoms only now and then. Others have a more severe case and regularly experience diarrhea and pain, as well as other complications. Crohn's disease can go into remission, in which case symptoms may go away for months or even years. Unfortunately, symptoms usually return at some point. If this happens, the person may even need to be hospitalized during severe flare-ups.
Finally, age may influence the symptoms. For example, children with the condition often have different symptoms of Crohn's disease from those seen in adults.
The most common Crohn's disease symptoms are abdominal pain (stomach pain), often in the lower-right part of the abdomen, and chronic diarrhea, which can be bloody. Two other common symptoms include a low-grade fever and fatigue.
People who have a mild case of Crohn's disease usually have:
Diarrhea up to four times a day
Little or no abdominal pain (stomach pain)
Few or no other symptoms.
If your Crohn's disease is more severe, you may have:
Diarrhea more than six times a day
Severe abdominal pain
Weight loss
Other symptoms.
In addition to the common symptoms, other symptoms of Crohn's disease can include:
Abdominal cramps
Decreased appetite
Rectal bleeding
Bloating
Constipation
Vomiting
Pain, sores, and/or bleeding in or around the anus
Anal fissures, which are tears or cracks in the lining of the anus.
In children, the symptoms of Crohn's disease are slightly different. In addition to diarrhea and abdominal pain, children commonly have a fever of an unknown cause and unexplained weight loss. Arthritis may also be an early sign of the disease in children. Children may also suffer delayed development and stunted growth.
Crohn's disease can also cause problems in areas other than the intestines. Some of these include:
Nutritional deficiencies
Osteoporosis (bone thinning)
Anemia
Joint tenderness
Arthritis, such as enteropathic arthritis or ankylosing spondylitis
Skin disorders
Inflammation of the eye or mouth
Liver disease, including hepatitis
Inflammation of the bile ducts
Kidney stones.
Possible Crohn's disease complications within the digestive tract may include:
Sores or ulcers
Fistulas
Abscesses
A bowel obstruction
Perforations (tears) in the intestines
Toxic megacolon
Cancer.
There are a few warning signs that may mean you need urgent medical attention. Contact your healthcare provider immediately if you have any of the following possibly serious symptoms of Crohn's disease:
Greater-than-usual amounts of bloody diarrhea or diarrhea more than six to ten times a day
Severe abdominal pain (stomach pain)
Abdominal swelling
Fever of 38°C (100°F) or above
Unusual fatigue or weakness
Bleeding heavily when you have a bowel movement
A bowel movement that contains only blood clots
Feeling groggy and disoriented.
These may be warning signs of complications or a severe flare-up of your condition, and you may need to be hospitalized for treatment.
Medications, dietary and lifestyle changes, nutritional supplementation, surgery, or a combination of these are often used in the treatment of Crohn's disease. Medications that may be prescribed include Azulfidine, Rowasa, Imuran, and Humira. There are several different surgical procedures that may be used as well; however, surgery is not a cure for Crohn's disease.
There is no cure for Crohn's disease. This means that for someone with the condition, treatment goals are focused on:
Controlling inflammation
Allowing the digestive tract to heal and then preventing flare-ups
Relieving Crohn's disease symptoms
Maintaining quality of life
Controlling nutritional deficiencies
Delaying the need for surgery.
Depending on how serious your condition is, your doctor may recommend one or several different treatments for Crohn's disease. These treatment options include:
Medications
Dietary changes
Other lifestyle changes
Nutritional supplementation
Surgery.
Your healthcare provider will consider a number of factors before deciding which specific treatment or treatments make the most sense for your particular situation. Some factors he or she will consider include:
The severity of your symptoms
Complications you may be experiencing
Other treatments you have tried in the past.
While this disease can seriously affect your life and may require special care at times, it's rarely life-threatening. Crohn's disease treatment may help reduce your symptoms and allow you to live an active life.
Your healthcare provider may prescribe medications to relieve inflammation in your digestive tract, reduce your body's immune response, or both.
Not everyone responds the same way to medicines, so your healthcare provider may have to try several before finding one that controls the disease with a minimum of side effects.
Medications used for the treatment of Crohn's disease include:
Sulfasalazine (Azulfidine)
Other aminosalicylates, including:
Mesalamine (Rowasa, Canasa, Asacol, and Pentasa)
Olsalazine (Dipentum)
Balsalazide (Colazal)
Corticosteroids, such as prednisone
Immunosuppressive drugs, including 6-mercaptopurine (6-MP, Purinethol) and azathioprine (Imuran)
Biologic response modifiers, including infliximab (Remicade), adalimumab (Humira), and certolizumab pegol (Cimzia)
Antibiotics
Antidiarrheal medicines.
There's no firm evidence that what you eat actually causes inflammatory bowel disease. But certain foods and beverages can aggravate your signs and symptoms, especially during a flare-up. If you think eating certain foods make your condition worse, keep a food diary to keep track of what you're eating as well as how you feel. If you discover some foods are causing your symptoms to flare, it's a good idea to try eliminating those foods. Here are some suggestions that may help:
Limit dairy products. Like many people with inflammatory bowel disease, you may find that problems, such as diarrhea, abdominal pain and gas, improve when you limit or eliminate dairy products. You may be lactose intolerant — that is, your body can't digest the milk sugar (lactose) in dairy foods. If so, limiting dairy or using an enzyme product, such as Lactaid, will help break down lactose.
Try low-fat foods. If you have Crohn's disease of the small intestine, you may not be able to digest or absorb fat normally. Instead, fat passes through your intestine, making your diarrhea worse. Foods that may be especially troublesome include butter, margarine, cream sauces and fried foods.
Limit fiber, if it's a problem food. For most people, high-fiber foods, such as fresh fruits and vegetables and whole grains, are the foundation of a healthy diet. But if you have inflammatory bowel disease, fiber may make diarrhea, pain and gas worse. If raw fruits and vegetables bother you, try steaming, baking or stewing them. You may also find that you can tolerate some fruits and vegetables, but not others. In general, you may have more problems with foods in the cabbage family, such as broccoli and cauliflower, and nuts, seeds, corn and popcorn.
Avoid problem foods. Eliminate any other foods that seem to make your signs and symptoms worse. These may include "gassy" foods such as beans, cabbage and broccoli, raw fruit juices and fruits, spicy food, popcorn, alcohol, and foods and drinks that contain caffeine, such as chocolate and soda.
Eat small meals. You may find you feel better eating five or six small meals a day rather than two or three larger ones.
Drink plenty of liquids. Try to drink plenty of fluids daily. Water is best. Alcohol and beverages that contain caffeine stimulate your intestines and can make diarrhea worse, while carbonated drinks frequently produce gas.
Consider multivitamins. Because Crohn's disease can interfere with your ability to absorb nutrients and because your diet may be limited, multivitamin and mineral supplements are often helpful. Check with your doctor before taking any vitamins or supplements.
Talk to a dietitian. If you begin to lose weight or your diet has become very limited, talk to a registered dietitian.
Beside diet, other lifestyle changes can help relieve Crohn's disease symptoms in some people. Some of these lifestyle changes include:
Quitting the use of tobacco products (if you use them)
Learning how to manage stress better
Seeking support through support groups or counseling.
Smoking
Smoking increases your risk of developing Crohn's disease, and
once you have it, smoking can make the condition worse. People with
Crohn's disease who smoke are more likely to have relapses, need
medications and repeat surgeries. Quitting smoking can improve the
overall health of your digestive tract, as well as provide many other
health benefits.
Stress
Although stress doesn't cause Crohn's disease, it can make your
signs and symptoms worse and may trigger flare-ups. Stressful events
can range from minor annoyances to a move, job loss or the death of a
loved one.
When you're stressed, your normal digestive process changes. Your stomach empties more slowly and secretes more acid. Stress can also speed or slow the passage of intestinal contents. It may also cause changes in intestinal tissue itself.
Although it's not always possible to avoid stress, you can learn ways to help manage it. Some of these include:
Exercise. Even mild exercise can help reduce stress, relieve depression and normalize bowel function. Talk to your doctor about an exercise plan that's right for you.
Biofeedback. This stress-reduction technique may help you reduce muscle tension and slow your heart rate with the help of a feedback machine. You're then taught how to produce these changes without feedback from the machine. The goal is to help you enter a relaxed state so that you can cope more easily with stress. Biofeedback is usually taught in hospitals and medical centers.
Regular relaxation and breathing exercises. One way to cope with stress is to regularly relax and use techniques such as deep, slow breathing to calm down.
Healthcare providers may recommend nutritional supplements, especially for children whose growth has been slowed. Special high-calorie liquid formulas are sometimes used for this purpose. A small number of people may need to be fed through an IV for a brief time. This procedure can help people who need extra nutrition temporarily, those whose intestines need to rest, or those whose intestines cannot absorb enough nutrition from food.
If medications and dietary and lifestyle changes aren't successful in treating Crohn's disease, surgery may be recommended. In fact, most people (up to 75 percent) with Crohn's disease will have some type of surgery during their lifetime.
There are several types of surgery that healthcare providers may recommend. These include:
Strictureplasty
Resection
Colectomy or proctocolectomy
Surgery for an abscess and/or fistula.
Surgery can help relieve symptoms or treat complications associated with the condition; however, surgery is not a cure for Crohn's disease. For example, if part of the colon or small intestine is removed, the inflammation tends to return next to the area of intestine that has been removed. Therefore, people considering surgery should carefully weigh its risks and benefits compared to those of other treatments.
Many people with digestive disorders have used some form of complementary or alternative therapy. Some commonly used therapies include:
Herbal and nutritional supplements
Probiotics
Fish oil
Acupuncture
Side effects and ineffectiveness of conventional therapies are primary reasons for seeking alternative care.
The majority of alternative therapies aren't regulated by the FDA. Manufacturers can claim that their therapies are safe and effective but don't need to prove it. In some cases that means you'll end up paying for products that don't work. For example, studies done on fish oil and on probiotics for the treatment of Crohn's haven't shown benefits to using these products. What's more, even natural herbs and supplements can have side effects and cause dangerous interactions. Tell your doctor if you decide to try any herbal supplement.
Some people may find acupuncture or hypnosis helpful for the management of Crohn's, but neither therapy has been well studied for this use.
Unlike probiotics — which are beneficial live bacteria that you consume — prebiotics are natural compounds found in plants, such as artichokes, that help fuel beneficial intestinal bacteria. An initial study on prebiotics had promising results. More studies are under way.
Medication, dietary and lifestyle changes, and surgery may help relieve or even eliminate your symptoms, but unfortunately, the relief is often only temporary. Crohn's disease is chronic in most people, which means that it never goes away for good. But it is common for people to have periods of time during which they have no symptoms. These symptom-free periods are called remissions, and they can last for months or even years.
Crohn's disease does not usually go away by itself. If you don't seek treatment, your symptoms may continue to get worse. Your risk of infection, bowel obstruction, and perforation can increase as well.
Relieving associated symptoms requires effort on your part. By following your healthcare provider's recommendations for Crohn's disease treatment, you may be able to relieve symptoms and improve the quality of your life.