What is Crohn's disease?
Crohn's disease is a lifelong inflammatory bowel disease (IBD). Parts of the digestive system get swollen and have deep sores called ulcers. Crohn's disease usually is found in the last part of the small intestine and the first part of the large intestine. But it can develop anywhere in the digestive tract, from the mouth to the anus.
What causes Crohn's disease?
Doctors don't know what causes Crohn's disease. You may get it when the body's immune system has an abnormal response to normal bacteria in your intestine. Other kinds of bacteria and viruses may also play a role in causing the disease.
Crohn's disease can run in families. Your chances of getting it are higher if a close family member has it. People of Eastern European (Ashkenazi) Jewish background may have a higher chance of getting Crohn's disease. Smoking also puts you at a higher risk for the disease.
What are the symptoms?
The main symptoms of Crohn's disease are belly pain and diarrhea (sometimes with blood). Some people may have diarrhea 10 to 20 times a day. Losing weight without trying is another common sign. Less common symptoms include mouth sores, bowel blockages, anal tears (fissures), and openings (fistulas) between organs.
Infections, hormonal changes, and smoking can cause your symptoms to flare up. You may have only mild symptoms or go for long periods of time without any symptoms. A few people have ongoing, severe symptoms.
It's important to be aware of signs that Crohn's disease may be getting worse. Call your doctor right away if you have any of these signs:
- You feel faint or have a fast and weak pulse.
- You have severe belly pain.
- You have a fever or shaking chills.
- You are vomiting again and again.
How is Crohn's disease diagnosed?
Your doctor will ask you about your symptoms and do a physical examination. You may also have X-rays and lab tests to find out if you have Crohn's.
Tests that may be done to diagnose Crohn's disease include:
- Barium X-rays of the small intestine or colon.
- Colonoscopy or flexible sigmoidoscopy. In these tests, the doctor uses a thin, lighted tube to look inside the colon.
- Biopsy. The doctor takes a sample of tissue and tests it to find out if you have Crohn's or another disease, such as cancer.
- Stool analysis. This is a test to look for blood and signs of infection in a sample of your stool.
- One or more imaging tests, such as CT scan or MRI.
How is it treated?
Your treatment will depend on the type of symptoms you have and how bad they are.
There are a few steps you can take to help yourself feel better. Take your medicine just as your doctor tells you to. Exercise, and eat healthy meals. Don't smoke. Smoking makes Crohn's disease worse.
The most common treatment for Crohn's disease is medicine. Mild symptoms of Crohn's disease may be treated with over-the-counter medicines to stop diarrhea. But talk with your doctor before you take them, because they may cause side effects.
You may also use prescription medicines. They help control inflammation in the intestines and keep the disease from causing symptoms. (When you don't have symptoms, you are in remission.) These medicines also help heal damaged tissue and can postpone the need for surgery.
Crohn's disease makes it hard for your body to absorb nutrients from food. A meal plan that focuses on high-calorie, high-protein foods can help you get the nutrients you need. Eating this way may be easier if you have regular meals plus two or three snacks each day.
How do you cope with Crohn's disease?
Having Crohn's disease can be stressful. The disease affects every part of your life. Seek support from family and friends to help you cope. Get counselling if you need it.
Many people with inflammatory bowel diseases look to alternative treatments to improve their well-being. These treatments haven't been proved effective for Crohn's disease, but they may help you cope. They include massage, supplements such as vitamins D and B12, and herbs like ginseng.
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The cause of Crohn's disease is unknown. This disease may result from an abnormal response by the body's immune system to normal intestinal bacteria.footnote 1 Disease-causing bacteria and viruses also may play a role.
Crohn's disease can run in families, so some people may be more likely than others to develop the condition when exposed to something that triggers an immune reaction. Environmental factors may also play a role in causing this disease.
The main symptoms of Crohn's disease include:
- Belly pain. The pain often is described as cramping and intermittent, and the belly may be sore when touched. Belly pain may turn to a dull, constant ache as the condition gets worse.
- Diarrhea. Some people may have diarrhea 10 to 20 times a day. They may wake up at night and need to go to the bathroom. Crohn's disease may cause blood in stools, but not always.
- Loss of appetite.
- Fever. In severe cases, fever or other symptoms that affect the entire body may develop. A high fever may mean that you have an infection, such as an abscess.
- Weight loss. Ongoing symptoms, such as diarrhea, can lead to weight loss.
- Too few red blood cells (anemia). Some people with Crohn's disease develop anemia because of low iron levels caused by bloody stools or the intestinal inflammation itself.
- Small tears in the anus (anal fissures) that may go away, but come back again.
Because Crohn's disease involves the immune system, you also may have symptoms outside the digestive tract. These may include joint pain, eye problems, a skin rash, or liver disease.
Crohn's disease is an ongoing (chronic) condition that may flare up throughout your life. It affects different people in different ways. Some people may have only mild symptoms. Others may have severe symptoms or complications that, in rare cases, may be life-threatening.
The disease may be:
- Not active (in remission).
Crohn's disease may be defined by the part of the digestive tract involved, such as the rectum and anus (perianal disease) or the area where the small intestine joins the large intestine (ileocecal disease). Some people may have features of both Crohn's disease and ulcerative colitis, the other major type of inflammatory bowel disease (IBD).
Because Crohn's disease can cause inflammation in parts of the intestines that absorb nutrients from food, it can cause deficiencies in vitamin B12, folic acid, or other nutrients. The disease can increase the risk of gallstones, kidney stones, and certain uncommon forms of anemia.
In long-term Crohn's disease, scar tissue may replace some of the inflamed or ulcerated intestines. This scar tissue can form blockages (bowel obstructions) or narrowed areas (strictures) that can prevent stool from passing through the intestines. Blockages in the intestines also can be caused by inflammation and swelling, which may improve with medicines. Sometimes blockages can only be treated with surgery.
If sores break through the wall of the intestines, abnormal connections or openings (fistulas) may form. Fistulas can form between two parts of the intestines, between the intestines and other organs (such as the bladder or vagina), or between the intestines and the skin. In rare cases, this can lead to infection of the abdominal wall.
Crohn's disease of the colon and rectum that has been present for 8 years or longer increases the risk of cancer. With regular screening, some cancers can be found early and treated successfully.
Most women who have Crohn's disease can have a normal pregnancy and deliver a healthy baby. The best idea is to wait until the disease is in remission before becoming pregnant. Women who become pregnant when their disease is under control are more likely to avoid flare-ups during pregnancy.
Some medicines used to treat the disease can be used during pregnancy. It's a good idea to talk with your doctor about which medicines are okay. But sometimes severe Crohn's disease can harm your baby more than medicines to keep it under control.
What Increases Your Risk
Things that may increase your risk of getting Crohn's disease include:
- Having a family history of Crohn's disease. Your risk increases if an immediate family member (a parent, brother, or sister) has the disease.
- Having Ashkenazi Jewish ancestry.
- Smoking cigarettes.
Things that may cause Crohn's disease symptoms to flare up include:
- Hormonal changes.
- Lifestyle changes.
When should you call your doctor?
Call a doctor right away if you have been diagnosed with Crohn's disease and you have one or more of the following:
- Fever or shaking chills
- Light-headedness, passing out, or rapid heart rate
- Stools that are almost always bloody
- Severe dehydration
- Severe belly pain or severe pain and bloating
- Evidence of pus draining from the area around the anus, or pain and swelling in the anal area
- Repeated vomiting
- Not passing any stools or gas
If you have any of these symptoms and you have been diagnosed with Crohn's disease, your condition may have become much worse. Some of these symptoms also may be signs of toxic megacolon. This is a rare complication of Crohn's disease that requires emergency treatment. Untreated toxic megacolon can cause the colon to leak or rupture, which can be fatal.
People who have Crohn's disease usually know their normal pattern of symptoms. Call your doctor if there is a change in your usual symptoms or if:
- Your symptoms become significantly worse than usual.
- You have diarrhea that lasts for more than 2 weeks.
- You have lost weight.
Who to see
To be evaluated for surgery, you may be referred to a:
Examinations and Tests
Crohn's disease is diagnosed through a medical history and physical examination, imaging tests to look at the intestines, and lab tests.
It may go undiagnosed for years, because symptoms usually develop gradually and it doesn't always affect the same part of the intestine.
Other diseases can have the same symptoms as Crohn's disease. But doctors can diagnose Crohn's by doing a test that looks at the inside of the intestine.
- Colonoscopy or flexible sigmoidoscopy: Colonoscopy is often the preferred test because it can be used to examine the entire colon. Sigmoidoscopy reaches only the lowest part of the colon.
- Abdominal X-ray: This test can show possible obstructions in the belly.
- Upper gastrointestinal (UGI) series: It examines the upper part of the digestive tract.
- Upper gastrointestinal endoscopy: It looks at the interior lining of your esophagus, stomach, and duodenum.
- Barium enema: This test looks at the large intestine (colon).
- Computed tomography (CT) scan: This test uses X-rays to make detailed pictures inside the body.
- Magnetic resonance imaging (MRI): MRI uses a magnetic field and pulses of radio wave energy to provide pictures of organs and structures inside the body.
- Standard blood tests and urine tests: These check for anemia, inflammation, or malnutrition. Depending on the symptoms, an erythrocyte sedimentation rate (ESR, or sed rate) or C-reactive protein (CRP) blood test may be done to look for infection or inflammation.
Other tests may be done to confirm or evaluate the disease.
- Biopsy: This test is done on a sample of tissue collected during sigmoidoscopy or colonoscopy. A biopsy also may be done to find out if a tumour is present. Bowel biopsies are painless (other than the possible discomfort of the scope procedure). They remove only a tiny piece of tissue.
- Stool analysis: This may be done to look for blood, signs of bacterial infection, malabsorption, parasites, or the presence of white blood cells. It can help tell the difference between Crohn's disease and irritable bowel syndrome (IBS), which can have similar symptoms.
- Video capsule endoscopy (VCE): This test takes pictures of the digestive tract using a tiny camera that you swallow. The images are recorded by a device that you wear on your belt. The test allows your doctor to see the small intestine, which is hard to see with other tests.
- Small bowel enteroscopy: This test uses a long, lighted flexible tube with a tiny camera that sends pictures of the small intestine to a video screen. This helps the doctor look at the small intestine. The doctor can also take small samples of the tissue.
- Blood tests to find antibodies: These tests can sometimes help the doctor tell if you have Crohn's disease or ulcerative colitis. These tests include anti-neutrophil cytoplasmic antibody with perinuclear staining (pANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and outer membrane porin C (Omp C).
The main treatment for Crohn's disease is medicine to stop the inflammation in the intestine and medicine to prevent flare-ups and keep you in remission. A few people have severe, long-lasting symptoms or complications that may require a stronger medicine, a combination of medicines, or surgery. The type of treatment you need depends on the type of symptoms you have and how bad they are.
Mild symptoms may respond to an antidiarrheal medicine such as loperamide (Imodium, for example). This medicine slows or stops the painful spasms in your intestines that cause symptoms.
For mild to moderate symptoms, your doctor may have you take antibiotics. Sometimes aminosalicylates are used.
Severe symptoms may be treated with corticosteroids, immunomodulator medicines, or biologics. With severe symptoms, the first step is to control the disease. When your symptoms are gone, your doctor will plan your treatment to keep you symptom-free (in remission).
After symptoms are controlled, your treatment will focus on medicine or a combination of medicines that keeps Crohn's disease in remission.
Your doctor will want to see you about every 6 months if your condition is stable. You'll be seen more often if you have flare-ups. You may have lab tests every 2 to 3 months.
Some severe cases of Crohn's disease need to be treated in the hospital. In the hospital, you may get supplemental nutrition through a tube placed in your nose and down into the stomach (enteral nutrition). Or your bowel may need to rest, and you will be fed liquid nutrients in a vein (total parenteral nutrition, TPN). See Other Treatment.
Surgery may be needed if no medicine is effective or if you have complications. See Surgery.
Crohn's disease cannot be prevented, because the cause is unknown. But you can take steps to reduce the severity of the disease. For help, see Home Treatment.
If Crohn's disease doesn't cause symptoms, no treatment is needed. Mild symptoms may be treated with antidiarrheal medicines or changes in diet and nutrition.
In general, doctors recommend that you do not use non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen. These medicines may cause flare-ups of Crohn's disease. But some people may be more likely to have flare-ups from NSAIDs than others. Talk to your doctor about whether to avoid these medicines.
You can also help yourself by:
- Not smoking. Smoking makes Crohn's disease worse.
- Eating a healthy diet.
- Not using antibiotics unless they have been prescribed for you by a doctor.
- Getting regular exercise.
Support and counselling
Crohn's disease can affect every aspect of your life. It may make you feel isolated or depressed. But you can take steps to improve your outlook and coping skills. You may want to seek professional counselling and social support from family, friends, or clergy.
Helping your child
Children who have Crohn's disease may feel self-conscious if they don't grow as fast as other children their age. Encourage your child to take medicine as prescribed. Offer help with the treatment so that your child can feel better, start growing again, and lead a more normal life. Children tend to have a harder time managing the disease than adults, so your support is especially important.
Medicines usually are the treatment of choice for Crohn's disease. They can control or prevent inflammation in the intestines and help to:
- Relieve symptoms.
- Promote healing of damaged tissues.
- Put the disease into remission and keep it from flaring up again.
- Postpone the need for surgery.
The choice of medicine usually depends on how severe the disease is, what part of the intestine is affected, and whether complications are present. Medicines for Crohn's disease include:
- Aminosalicylates, such as mesalamine or sulfasalazine. Your doctor may recommend these medicines during a flare-up or at other times.
- Antibiotics. These may be tried to treat the disease itself or to treat infections that can occur with Crohn's disease. They are also used to treat fistulas and abscesses.
- Biologics, such as infliximab or adalimumab. Your doctor may have you try these medicines if other medicines for Crohn's disease haven't worked for you. In some cases, biologics are tried before some of the other medicines. They are also used to treat fistulas.
- Corticosteroids, such as budesonide or prednisone. These may be given for a few weeks or months to control swelling. These steroid medicines usually stop symptoms and put the disease in remission. But they are not used as long-term treatment to keep symptoms from coming back.
- Immune modulators, such as azathioprine and methotrexate. You may take these if other medicines don't work, if your symptoms come back when you stop taking steroid medicines, or if your symptoms come back often, even with treatment.
Surgery for Crohn's disease may be done if:
- No medicine can control your symptoms.
- You have serious side effects from medicines.
- Your symptoms can only be controlled with long-term use of corticosteroids.
- You have complications.
Surgery is rarely done, and it's not a cure. When surgery for Crohn's is needed, as little of the intestine as possible is removed to keep the intestines working normally. The disease tends to return to other areas of the intestines after surgery.
Surgery may improve a child's well-being and quality of life and restore normal growth and sexual development.
Types of surgery
- Bowel resection . The diseased portion of the intestine is removed, and the healthy ends of the intestine are reattached.
- Strictureplasty. The surgeon makes a lengthwise cut in the intestine and then sews the opening together in the opposite direction. This makes the intestine wider and helps with obstruction of the bowels. This is sometimes done at the same time as resection or when a person has had resection in the past. Strictureplasty is used when the doctor is trying to save as much of the intestine as possible.
- Proctocolectomy and ileostomy . The surgeon removes the large intestine and rectum, leaving the lower end of the small intestine (the ileum). The anus is sewn closed, and a small opening called a stoma is made in the skin of the lower belly. The ileum is connected to the stoma, creating an opening to the outside of the body. Stool empties from this opening into a small plastic pouch called an ostomy bag that is applied to the skin around the stoma.
- Intestinal transplant . This is rarely used for Crohn's disease. In this complex procedure, the small intestine is removed and replaced with the small intestine of a person who has recently died and donated his or her organs.
What to think about
It may take time to adjust to living with an ostomy. It may help to know that most people are able to adapt and resume all of their usual activities. Talk with your doctor about support groups in your area for people with ostomies.
Other treatments for Crohn's disease include balloon dilation, supplemental nutrition, and complementary therapies.
Balloon dilation isn't surgery. It may be done if you want to delay surgery, or if you have had surgery before and your doctor wants to save as much of the intestine as possible.
During the procedure, the doctor moves an endoscope through your intestine from your anus. The endoscope is a long, thin tube that has a video camera on the end. An uninflated balloon is placed across the narrowed part of the intestine. When the balloon is inflated, it makes that part of the intestine wider.
The balloon is deflated and then removed. Not as much is known about the long-term success of balloon dilation compared to surgery.
Some people who have Crohn's disease need additional nutrition because severe disease prevents their small intestine from absorbing nutrients.
Supplemental liquid feedings may be done through a tube placed in the nose and down into the stomach (enteral nutrition) or through a vein (total parenteral nutrition, or TPN). Enteral nutrition or TPN may be needed when:
- Crohn's disease isn't controlled with standard treatment.
- Short bowel syndrome occurs. This happens when so much of the small intestine has been surgically removed or is affected by the disease that you can't properly digest food and absorb enough nutrients.
- Bowel blockage occurs.
Supplemental feeding can restore good nutrition to children who are growing more slowly than normal. It also can build strength if you need surgery or have been weakened because of severe diarrhea and poor nutrition.
Supplemental nutrition allows the intestines to rest and heal. But it's common for symptoms to return when TPN is stopped and you go back to a regular diet. TPN doesn't change the long-term outcome of Crohn's disease.
Many people with inflammatory bowel disease consider non-traditional or complementary medicine in addition to prescription medicines. They may turn to these alternatives because there is no cure for Crohn's disease. People may also use complementary medicine for help with:
- The difficult side effects from standard medicines.
- The emotional strain of dealing with a chronic illness.
- The negative impact of severe disease on daily life.
These therapies have not been proved effective for Crohn's disease, but they may improve your well-being. Therapies include:
- Special diets or nutritional supplements, such as probiotics, evening primrose, and fish oils.
- Vitamin supplements, such as vitamins D and B12.
- Herbs, such as ginseng.
- Stimulation of the feet, hands, and ears to try to affect parts of the body (reflexology).
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Other Works Consulted
- Feuerstein JD, et al. (2017). American Gastroenterological Association Institute guideline on therapeutic drug monitoring in inflammatory bowel disease. Gastroenterology, 153(3): 827–834. DOI: 10.1053/j.gastro.2017.07.032. Accessed June 25, 2018.
- Lichtenstein GR, et al. (2018). ACG clinical guideline: Management of Crohn's disease in adults. American Journal of Gastroenterology, 113(4): 481–517. DOI: 10.1038/ajg.2018.27. Accessed July 12, 2018.
- Terdiman JP, et al. (2013). American Gastroenterological Association Institute guideline on the use of thiopurines, methotrexate, and anti-TNF-α biologic drugs for the induction and maintenance of remission in inflammatory Crohn's disease. Gastroenterology, 145(6): 1459–1463. DOI: 10.1053/j.gastro.2013.10.047. Accessed June 25, 2018.
Current as of: August 12, 2019
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Arvydas D. Vanagunas MD - Gastroenterology
Current as of: August 12, 2019