Crohn’s disease is a chronic inflammatory disease of the digestive tract. Symptoms include abdominal pain and diarrhea, sometimes bloody, and weight loss. Crohn’s treatment consists of lifestyle changes, such as exercise and a healthy diet, as well as over-the-counter antidiarrhetics and prescription anti-inflammatory medication.
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.
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.
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.
Your doctor will ask you about your symptoms and do a physical exam. 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.
What Causes Crohn’s Disease?
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Although there are many theories about what causes Crohn’s disease, none of them have been proven. There is a benefit, though, in understanding the possible causes of Crohn’s disease and how they interact with one another. Doing so can help one better understand the symptoms, diagnosis, and treatment of Crohn’s disease.
How do immune system problems relate to Crohn’s disease?
Scientists have linked immune system problems to inflammatory bowel disease (IBD), including Crohn’s. Usually, cells of the immune system defend the body from harmful microbes — bacteria, viruses, fungi, and other foreign substances — that have entered it. The body doesn’t usually respond to all microbes, however. Many microbes are helpful, especially for digestion. And so the immune system leaves them alone.
If there is an invader that needs to be eliminated, your body’s defense reaction begins. This immune system response causes inflammation. Immune system cells, chemicals, and fluids flood to the site to overcome the offending substance. After the substance has been disabled or removed, the immune response ends. Inflammation subsides.
For some reason, though, people with Crohn’s disease have an immune system that reacts inappropriately. The immune system may be defending the body against helpful microbes by mistake. Or, for some other reason, the inflammatory response simply will not stop. Either way, over time, this chronic inflammation in the digestive system can result in ulcers and other injuries to the intestines.
Is genetics connected to Crohn’s disease?
Brothers, sisters, children, and parents of persons with IBD, including Crohn’s disease, are slightly more likely to develop the disease themselves. About 10% to 20% of people with Crohn’s disease have at least one other family member who also has the disease. The condition is more common in certain ethnic groups, such as Jews, and is more prevalent in Caucasians.
Is this tendency toward IBD and Crohn’s disease passed genetically? Scientists have identified a gene associated with Crohn’s disease. This gene helps the body decide how to react to certain microbes. If the gene has changed or mutated in some way, your body’s reaction to microbes may also be different from the normal reaction. Over time, IBD or Crohn’s disease may develop. People with Crohn’s disease have this mutated gene twice as often as people who do not have the disease.
Do environmental factors play a role in Crohn’s disease, too?
Environmental factors may help trigger Crohn’s disease. Also, it should be noted that because a potential trigger is linked or associated to a condition does not mean that it causes it. Associated environmental factors may include any of the following:
- Substances from something you’ve eaten
- Microbes such as bacteria or viruses
- Cigarette smoke
- Other substances that are yet unknown
Environmental factors may contribute to Crohn’s disease in one of these two ways:
- They may trigger an immune system response. Once started, the response cannot stop.
- They may directly damage the lining of the intestines. This may cause Crohn’s disease to begin or to speed up.
What can I do to control Crohn’s disease?
The factors involved in causing Crohn’s disease are complex. Scientists continue to seek more information about the causes — in hopes of finding better ways to diagnose, treat, and perhaps even cure this frustrating and painful disease. In the meantime, understanding current theories about the causes of Crohn’s disease can help you work with your doctor to explore how various treatments might work to control this condition.
Crohn’s Disease – Symptoms
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 diseasedevelop 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 Complications
Complications of Crohn’s disease may be related or unrelated to the inflammation within the intestine. Intestinal complications of Crohn’s disease include obstruction and perforation of the small intestine orcolon, abscesses (collections of pus), fistulae, and intestinal bleeding. Massive distention or dilatation of the colon (megacolon) and rupture (perforation) of the intestine are potentially life-threatening complications. Both may require surgery, but, fortunately, these two complications are rare. Recent data suggest that there is an increased risk of cancer of the small intestine and colon in patients with long-standing Crohn’s disease, but studies are conflicting.
Other complications involve the skin, joints, spine, eyes, liver, and bile ducts. Skin involvement includes painful, red, and raised spots on the legs (erythema nodosum) and an ulcerating skin condition generally found around the ankles called pyoderma gangrenosum. Painful eyeconditions (uveitis, episcleritis) can cause visual difficulties. Arthritiscan cause pain, swelling, and stiffness of the joints of the extremities. Inflammation of the low back (sacroiliac joint arthritis) and of the spine(ankylosing spondylitis) can cause pain and stiffness. Inflammation of the liver (hepatitis) or bile ducts (primary sclerosing cholangitis) also can occur. Sclerosing cholangitis causes narrowing and obstruction of the ducts draining the liver and can lead to yellow skin (jaundice), recurrent bacterial infections, and liver cirrhosis with liver failure. Sclerosing cholangitis with liver failure is one of the reasons for performing a liver transplant. Sclerosing cholangitis often is complicated by the development of cancer of the bile ducts orgallbladder. People who also have cirrhosis are at increased risk of developing liver cancer.
Diagnosing Crohn’s Disease
There isn’t any one test that can tell you whether or not you haveCrohn’s disease. And Crohn’s disease has many possible symptoms that are the same as symptoms for other health problems. So, to make a diagnosis of Crohn’s disease, your doctor is likely to gather information from multiple sources. You’ll probably go through a combination of exams, lab tests, and imaging studies with these goals in mind:
- Rule out other health problems that have similar symptoms
- Make a clear diagnosis of Crohn’s disease
- Determine exactly which part of the digestive tract is affected
Diagnosing Crohn’s disease: Physical Exam and History
Your doctor will begin by gathering information about your health history and conducting a physical exam. Findings that may indicate further tests are needed include:
- Diarrhea, which may be bloody
- Family history of Crohn’s disease
- Pain and tenderness in the abdomen
Diagnosing Crohn’s Disease: Lab Tests
Your doctor may request lab tests in order to look for any problems that might be linked to Crohn’s disease. These tests check for signs of infection, inflammation, internal bleeding, and low levels of substances such as iron, protein, or minerals. Lab tests may include:
- Blood protein levels
- Blood sedimentation rates
- Body mineral levels
- Red blood cell counts
- Stool samples to check for blood or infectious microbes
- White blood cell counts
Diagnosing Crohn’s Disease: Imaging Studies and Endoscopy
Crohn’s disease may appear anywhere along the gastrointestinal tract, from the mouth to the rectum. X-rays and other images can help identify the severity and location of Crohn’s disease. These studies may include the following:
Diagnosing Crohn’s Disease: Barium X-rays and Other X-rays
A barium X-ray can show where and how severe Crohn’s disease is. It is especially helpful for finding any problems in parts of the small intestine that can’t be easily viewed by other techniques.
A chalky fluid containing barium is given by mouth or through the rectum. When barium fluid is given by mouth, it is called an upper GIseries. When barium fluid is placed in the rectum, it is called a barium enema. The barium fluid flows through the intestines, appearing white on X-ray film. This makes it easier to view problem areas. On a barium X-ray, your doctor may be able to see ulcers, narrowed areas of the intestine, abnormal connections between organs, known as fistulae, or other problems.
If barium X-rays show some sign of disease, your doctor may request other X-rays or imaging studies. These X-rays can help identify exactly how much of your digestive tract is affected by Crohn’s disease.
Diagnosing Crohn’s Disease: CT Scans
CT scanning uses computer-aided X-ray techniques to produce more detailed images of the abdomen and pelvis than can be seen in traditional X-rays. CT scans can help detect abscesses that might not show up on other X-rays. Abscesses are small pockets of infection.
Diagnosing Crohn’s Disease: Colonoscopy or Sigmoidoscopy
Colonoscopy and sigmoidoscopy allow the doctor to directly view the large intestine, which is the lower part of the digestive tract. These techniques can often provide the most accurate information about the intestines. They may be better at detecting small ulcers or inflammation than other techniques. They can be used to assess the severity of any inflammation. Colonoscopy is the most important tool in diagnosing Crohn’s disease.
During these procedures, a flexible viewing tube is placed through theanus into the large intestine. An image of the inside of the intestine is often projected onto a video monitor. A sigmoidoscopy involves examining the lowest part of the large intestine. A colonoscopy can provide a view of all of the large intestine and often the end of the small intestine, which is frequently affected by Crohn’s. In either case, the doctor can directly view the colon to check for signs of ulcers, inflammation, or bleeding. The doctor can also take small samples of tissue to examine under a microscope, known as a biopsy. This helps determine whether the tissue shows signs of Crohn’s disease or other problems.
Diagnosing Crohn’s Disease: Video Capsule Endoscopy
For video capsule endoscopy, you swallow a small capsule or pill that holds a miniature video camera. As it travels through the small intestine, it sends images of the lining to a receiver you wear on a belt around your waist. The images are downloaded and reviewed at a computer. The images can provide detailed information about early, mild problems associated with Crohn’s disease. This technique may be especially helpful if you have symptoms of Crohn’s disease but barium X-rays do not show evidence of the condition.
While video endoscopy can provide valuable information, there are times when it may be best to avoid it:
- If you have an obstruction in the small intestine, the capsule could get stuck and make the obstruction worse.
- If you have a narrowing in the small intestine, such as from Crohn’s disease, previous surgery, or previous radiation therapy, the capsule might become stuck.
- Some doctors worry that wireless transmissions from the capsule might interfere with implanted cardiac pacemakers or defibrillators.
Making a Diagnosis of Crohn’s Disease
After the exams, lab tests, and imaging tests are done, your doctor will discuss the findings with you. If your doctor believes you have Crohn’s disease, then you can work together to develop a treatment plan to manage the symptoms and control the disease.