Crohn's Disease
Overview
Gastroenterology & GI Surgery Blog
Connect with others and follow the latest advances in treating Crohn's disease and ulcerative colitis on Mayo Clinic Connect.Crohn's disease is a type of inflammatory bowel disease (IBD). It causes swelling of the tissues (inflammation) in your digestive tract, which can lead to abdominal pain, severe diarrhea, fatigue, weight loss and malnutrition.
Inflammation caused by Crohn's disease can involve different areas of the digestive tract in different people, most commonly the small intestine. This inflammation often spreads into the deeper layers of the bowel.
Crohn's disease can be both painful and debilitating, and sometimes may lead to life-threatening complications.
There's no known cure for Crohn's disease, but therapies can greatly reduce its signs and symptoms and even bring about long-term remission and healing of inflammation. With treatment, many people with Crohn's disease are able to function well.
Symptoms
In Crohn's disease, any part of your small or large intestine can be involved. It may involve multiple segments, or it may be continuous. In some people, the disease is only in the colon, which is part of the large intestine.
Signs and symptoms of Crohn's disease can range from mild to severe. They usually develop gradually, but sometimes will come on suddenly, without warning. You may also have periods of time when you have no signs or symptoms (remission).
When the disease is active, symptoms typically include:
- Diarrhea
- Fever
- Fatigue
- Abdominal pain and cramping
- Blood in your stool
- Mouth sores
- Reduced appetite and weight loss
- Pain or drainage near or around the anus due to inflammation from a tunnel into the skin (fistula)
Other signs and symptoms
People with severe Crohn's disease may also experience symptoms outside of the intestinal tract, including:
- Inflammation of skin, eyes and joints
- Inflammation of the liver or bile ducts
- Kidney stones
- Iron deficiency (anemia)
- Delayed growth or sexual development, in children
When to see a doctor
See your doctor if you have persistent changes in your bowel habits or if you have any of the signs and symptoms of Crohn's disease, such as:
- Abdominal pain
- Blood in your stool
- Nausea and vomiting
- Diarrhea lasting more than two weeks
- Unexplained weight loss
- Fever in addition to any of the above symptoms
Causes
The exact cause of Crohn's disease remains unknown. Previously, diet and stress were suspected, but now doctors know that these factors may aggravate, but don't cause, Crohn's disease. Several factors likely play a role in its development.
- Immune system. It's possible that a virus or bacterium may trigger Crohn's disease; however, scientists have yet to identify such a trigger. When your immune system tries to fight off an invading microorganism or environmental triggers, an atypical immune response causes the immune system to attack the cells in the digestive tract, too.
- Heredity. Crohn's disease is more common in people who have family members with the disease, so genes may play a role in making people more likely to have it. However, most people with Crohn's disease do not have a family history of the disease.
Risk factors
Risk factors for Crohn's disease may include:
- Age. Crohn's disease can occur at any age, but you're likely to develop the condition when you're young. Most people who develop Crohn's disease are diagnosed before they're around 30 years old.
- Ethnicity. Although Crohn's disease can affect any ethnic group, whites have the highest risk, especially people of Eastern European (Ashkenazi) Jewish descent. However, the incidence of Crohn's disease is increasing among Black people who live in North America and the United Kingdom. Crohn's disease is also being increasingly seen in the Middle Eastern population and among migrants to the United States.
- Family history. You're at higher risk if you have a first-degree relative, such as a parent, sibling or child, with the disease. As many as 1 in 5 people with Crohn's disease has a family member with the disease.
- Cigarette smoking. Cigarette smoking is the most important controllable risk factor for developing Crohn's disease. Smoking also leads to more-severe disease and a greater risk of having surgery. If you smoke, it's important to stop.
- Nonsteroidal anti-inflammatory medications. These include ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve), diclofenac sodium and others. While they do not cause Crohn's disease, they can lead to inflammation of the bowel that makes Crohn's disease worse.
Complications
Crohn's disease may lead to one or more of the following complications:
- Bowel obstruction. Crohn's disease can affect the entire thickness of the intestinal wall. Over time, parts of the bowel can scar and narrow, which may block the flow of digestive contents, often known as a stricture. You may require surgery to widen the stricture or sometimes to remove the diseased portion of your bowel.
- Ulcers. Chronic inflammation can lead to open sores (ulcers) anywhere in your digestive tract, including your mouth and anus, and in the genital area (perineum).
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Fistulas. Sometimes ulcers can extend completely through the intestinal wall, creating a fistula — an abnormal connection between different body parts. Fistulas can develop between your intestine and your skin, or between your intestine and another organ. Fistulas near or around the anal area (perianal) are the most common kind.
When fistulas develop inside the abdomen, it may lead to infections and abscesses, which are collections of pus. These can be life-threatening if not treated. Fistulas may form between loops of bowel, in the bladder or vagina, or through the skin, causing continuous drainage of bowel contents to your skin.
- Anal fissure. This is a small tear in the tissue that lines the anus or in the skin around the anus where infections can occur. It's often associated with painful bowel movements and may lead to a perianal fistula.
- Malnutrition. Diarrhea, abdominal pain and cramping may make it difficult for you to eat or for your intestine to absorb enough nutrients to keep you nourished. It's also common to develop anemia due to low iron or vitamin B-12 caused by the disease.
- Colon cancer. Having Crohn's disease that affects your colon increases your risk of colon cancer. General colon cancer screening guidelines for people without Crohn's disease call for a colonoscopy at least every 10 years beginning at age 45. In people with Crohn's disease affecting a large part of the colon, a colonoscopy to screen for colon cancer is recommended about 8 years after disease onset and generally is performed every 1 to 2 years afterward. Ask your doctor whether you need to have this test done sooner and more frequently.
- Skin disorders. Many people with Crohn's disease may also develop a condition called hidradenitis suppurativa. This skin disorder involves deep nodules, tunnels and abscesses in the armpits, groin, under the breasts, and in the perianal or genital area.
- Other health problems. Crohn's disease can also cause problems in other parts of the body. Among these problems are low iron (anemia), osteoporosis, arthritis, and gallbladder or liver disease.
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Medication risks. Certain Crohn's disease drugs that act by blocking functions of the immune system are associated with a small risk of developing cancers such as lymphoma and skin cancers. They also increase the risk of infections.
Corticosteroids can be associated with a risk of osteoporosis, bone fractures, cataracts, glaucoma, diabetes and high blood pressure, among other conditions. Work with your doctor to determine risks and benefits of medications.
- Blood clots. Crohn's disease increases the risk of blood clots in veins and arteries.
Diagnosis
Your doctor will likely diagnose Crohn's disease only after ruling out other possible causes for your signs and symptoms. There is no single test to diagnose Crohn's disease.
Your doctor will likely use a combination of tests to help confirm a diagnosis of Crohn's disease, including:
Lab tests
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Blood tests. Your doctor may suggest blood tests to check for anemia — a condition in which there aren't enough red blood cells to carry adequate oxygen to your tissues — or to check for signs of infection.
Your doctor may also perform other tests to check for levels of inflammation, liver function, or the presence of inactive infections, such as tuberculosis. Your blood may also be screened for the presence of immunity against infections.
- Stool studies. You may need to provide a stool sample so that your doctor can test for hidden (occult) blood or organisms, such as infection-causing bacteria or, rarely, parasites in your stool.
Procedures
- Colonoscopy. This test allows your doctor to view your entire colon and the very end of your ileum (terminal ileum) using a thin, flexible, lighted tube with a camera at the end. During the procedure, your doctor can also take small samples of tissue (biopsy) for laboratory analysis, which may help to make a diagnosis. Clusters of inflammatory cells called granulomas may help suggest a diagnosis of Crohn's.
Computerized tomography (CT). You may have a CT scan — a special X-ray technique that provides more detail than a standard X-ray does. This test looks at the entire bowel as well as at tissues outside the bowel.
CT enterography is a special CT scan that involves drinking an oral contrast material and getting intravenous contrast images of the intestines. This test provides better images of the small bowel and has replaced barium X-rays in many medical centers.
Magnetic resonance imaging (MRI). An MRI scanner uses a magnetic field and radio waves to create detailed images of organs and tissues. MRI is particularly useful for evaluating a fistula around the anal area (pelvic MRI) or the small intestine (MR enterography).
Sometimes an MR enterography can be performed to check for disease status or progression. This test may be used instead of CT enterography to reduce the risk of radiation, especially in younger people.
Capsule endoscopy. For this test, you swallow a capsule that has a camera in it. The camera takes pictures of your small intestine and sends them to a recorder you wear on your belt. The images are then downloaded to a computer, displayed on a monitor and checked for signs of Crohn's disease. The camera exits your body painlessly in your stool.
You may still need endoscopy with biopsy to confirm the diagnosis of Crohn's disease. Capsule endoscopy should not be performed if there is a suspected stricture or blockage (obstruction) in the bowel.
- Balloon-assisted enteroscopy. For this test, a scope is used along with a device called an overtube. This enables the doctor to look further into the small bowel where standard endoscopes don't reach. This technique is useful when capsule endoscopy shows abnormalities but the diagnosis is still in question.
Treatment
There is currently no cure for Crohn's disease, and there is no single treatment that works for everyone. One goal of medical treatment is to reduce the inflammation that triggers your signs and symptoms. Another goal is to improve long-term prognosis by limiting complications. In the best cases, this may lead not only to symptom relief but also to long-term remission.
Anti-inflammatory drugs
Anti-inflammatory drugs are often the first step in the treatment of inflammatory bowel disease. They include:
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Corticosteroids. Corticosteroids such as prednisone and budesonide (Entocort EC) can help reduce inflammation in your body, but they don't work for everyone with Crohn's disease.
Corticosteroids may be used for short-term (3 to 4 months) symptom improvement and to induce remission. Corticosteroids may also be used in combination with an immune system suppressor to induce the benefit from other medications. They are then eventually tapered off.
- Oral 5-aminosalicylates. These drugs are generally not beneficial in Crohn's disease. They include sulfasalazine (Azulfidine), which contains sulfa, and mesalamine (Delzicol, Pentasa, others). Oral 5-aminosalicylates were widely used in the past but now are generally considered of very limited benefit.
Immune system suppressors
These drugs also reduce inflammation, but they target your immune system, which produces the substances that cause inflammation. For some people, a combination of these drugs works better than one drug alone.
Immune system suppressors include:
- Azathioprine (Azasan, Imuran) and mercaptopurine (Purinethol, Purixan). These are the most widely used immunosuppressants for treatment of inflammatory bowel disease. Taking them requires that you follow up closely with your doctor and have your blood checked regularly to look for side effects, such as a lowered resistance to infection and inflammation of the liver. They may also cause nausea and vomiting.
- Methotrexate (Trexall). This drug is sometimes used for people with Crohn's disease who don't respond well to other medications. You will need to be followed closely for side effects.
Biologics
This class of therapies targets proteins made by the immune system. Types of biologics used to treat Crohn's disease include:
- Vedolizumab (Entyvio). This drug works by stopping certain immune cell molecules — integrins — from binding to other cells in your intestinal lining. Vedolizumab is a gut-specific agent and is approved for Crohn's disease. A similar medication to vedolizumab known as natalizumab was previously used for Crohn's disease but is no longer used due to side effect concerns, including a fatal brain disease.
- Infliximab (Remicade), adalimumab (Humira) and certolizumab pegol (Cimzia). Also known as TNF inhibitors, these drugs work by neutralizing an immune system protein known as tumor necrosis factor (TNF).
- Ustekinumab (Stelara). This was recently approved to treat Crohn's disease by interfering with the action of an interleukin, which is a protein involved in inflammation.
- Risankizumab (Skyrizi). This medication acts against a molecule known as interleukin-23 and was recently approved for treatment of Crohn's disease.
Antibiotics
Antibiotics can reduce the amount of drainage from fistulas and abscesses and sometimes heal them in people with Crohn's disease. Some researchers also think that antibiotics help reduce harmful bacteria that may be causing inflammation in the intestine. Frequently prescribed antibiotics include ciprofloxacin (Cipro) and metronidazole (Flagyl).
Other medications
In addition to controlling inflammation, some medications may help relieve your signs and symptoms. But always talk to your doctor before taking any nonprescription medications. Depending on the severity of your Crohn's disease, your doctor may recommend one or more of the following:
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Anti-diarrheals. A fiber supplement, such as psyllium powder (Metamucil) or methylcellulose (Citrucel), can help relieve mild to moderate diarrhea by adding bulk to your stool. For more severe diarrhea, loperamide (Imodium A-D) may be effective.
These medications could be ineffective or even harmful in some people with strictures or certain infections. Please consult your health care provider before you take these medications.
- Pain relievers. For mild pain, your doctor may recommend acetaminophen (Tylenol, others) — but not other common pain relievers, such as ibuprofen (Advil, Motrin IB, others) or naproxen sodium (Aleve). These drugs are likely to make your symptoms worse and can make your disease worse as well.
- Vitamins and supplements. If you're not absorbing enough nutrients, your doctor may recommend vitamins and nutritional supplements.
Nutrition therapy
Your doctor may recommend a special diet given by mouth or a feeding tube (enteral nutrition) or nutrients infused into a vein (parenteral nutrition) if you have Crohn's disease. This can improve your overall nutrition and allow the bowel to rest. Bowel rest may reduce inflammation in the short term.
Your doctor may use nutrition therapy short term and combine it with medications, such as immune system suppressors. Enteral and parenteral nutrition are typically used to get people healthier prior to surgery or when other medications fail to control symptoms.
Your doctor may also recommend a low residue or low-fiber diet to reduce the risk of intestinal blockage if you have a narrowed bowel (stricture). A low residue diet is designed to reduce the size and number of your stools.
Surgery
If diet and lifestyle changes, drug therapy, or other treatments don't relieve your signs and symptoms, your doctor may recommend surgery. Nearly half of those with Crohn's disease will require at least one surgery. However, surgery does not cure Crohn's disease.
During surgery, your surgeon removes a damaged portion of your digestive tract and then reconnects the healthy sections. Surgery may also be used to close fistulas and drain abscesses.
The benefits of surgery for Crohn's disease are usually temporary. The disease often recurs, frequently near the reconnected tissue. The best approach is to follow surgery with medication to minimize the risk of recurrence.
Clinical trials
Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.
Lifestyle and home remedies
Sometimes you may feel helpless when facing Crohn's disease. But changes in your diet and lifestyle may help control your symptoms and lengthen the time between flare-ups.
Diet
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.
It can be helpful to keep a food diary to track what you're eating, as well as how you feel. If you discover that some foods are causing your symptoms to flare, you can try eliminating them.
Here are some general dietary suggestions that may help to manage your condition:
- Limit dairy products. Many people with inflammatory bowel disease find that problems such as diarrhea, abdominal pain and gas improve by limiting or eliminating dairy products. You may be lactose intolerant — that is, your body can't digest the milk sugar (lactose) in dairy foods. Using an enzyme product such as Lactaid may help.
- Eat small meals. You may find that 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.
Smoking
Smoking increases your risk of developing Crohn's disease. And once you have Crohn's disease, smoking can make it worse. People with Crohn's disease who smoke are more likely to have relapses and 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. Although it's not always possible to avoid stress, you can learn ways to help manage it, such as:
- 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 decrease muscle tension and slow your heart rate with the help of a feedback machine. The goal is to help you enter a relaxed state so that you can cope more easily with stress.
- 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. You can take classes in yoga and meditation or use books, CDs or DVDs at home.
Alternative medicine
Many people with Crohn's disease have used some form of complementary and alternative medicine to treat their condition. However, there are few well-designed studies of the safety and effectiveness of these treatments.
Coping and support
Crohn's disease doesn't just affect you physically — it takes an emotional toll as well. If signs and symptoms are severe, your life may revolve around a constant need to run to the toilet. Even if your symptoms are mild, gas and abdominal pain can make it difficult to be out in public. All of these factors can alter your life and may lead to depression. Here are some things you can do:
- Be informed. One of the best ways to be more in control is to find out as much as possible about Crohn's disease. Look for information from the Crohn's & Colitis Foundation.
- Join a support group. Although support groups aren't for everyone, they can provide valuable information about your condition as well as emotional support. Group members frequently know about the latest medical treatments or integrative therapies. You may also find it reassuring to be among others with Crohn's disease.
- Talk to a therapist. Some people find it helpful to consult a mental health professional who's familiar with inflammatory bowel disease and the emotional difficulties it can cause.
Although living with Crohn's disease can be discouraging, research is ongoing and the outlook is improving.
Preparing for your appointment
Symptoms of Crohn's disease may first prompt you to visit your primary health care provider. Your provider may recommend that you see a specialist who treats digestive diseases (gastroenterologist).
Because appointments can be brief, and there's often a lot of information to discuss, it's a good idea to be well prepared. Here's some information to help you get ready, and what to expect from your provider.
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as restrict your diet.
- Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information, including any major stresses or recent life changes.
- Make a list of all medications, vitamins or supplements that you're taking.
- Ask a family member or friend to come with you to your appointment. Sometimes it can be difficult to take in all the information provided during an appointment. Someone who accompanies you may remember something that you missed or forgot.
Preparing a list of questions before you go can help you make the most of your visit. List your questions from most important to least important in case time runs out. For Crohn's disease, some basic questions to ask include:
- What's causing these symptoms?
- Are there other possible causes for my symptoms?
- What kinds of tests do I need? Do these tests require any special preparation?
- Is this condition temporary or long lasting?
- What treatments are available, and which do you recommend?
- Are there any medications that I should avoid?
- What types of side effects can I expect from treatment?
- Are there any alternatives to the approach that you're suggesting?
- I have other health conditions. How can I best manage them together?
- Do I need to follow any dietary restrictions?
- Is there a generic alternative to the medicine you're prescribing me?
- Are there any brochures or other printed material that I can take with me? What websites do you recommend?
- If I have Crohn's disease, what is the risk that my child will develop it?
- What kind of follow-up testing do I need in the future?
In addition to the questions that you've prepared, don't hesitate to ask additional questions during your appointment.
What to expect from your doctor
Your provider is likely to ask you a number of questions, including:
- When did you first begin experiencing symptoms?
- Have your symptoms been continuous or off and on?
- How severe are your symptoms?
- Do your symptoms affect your ability to work or do other activities?
- Does anything seem to improve your symptoms?
- Is there anything that you've noticed that makes your symptoms worse?
- Do you smoke?
- Do you take nonprescription or prescription nonsteroidal anti-inflammatory drugs (NSAIDs) — for example, ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve) or diclofenac sodium?