Inflammatory bowel disease (IBD) refers to a chronic (long term/ lifelong) inflammation or irritation of the stomach, small intestine and/or colon (large bowel). Inflammatory bowel disease should not be confused with irritable bowel syndrome (IBS). There are two types or categories of inflammatory bowel disease, Ulcerative Colitis and Crohn’s disease. Patients can have either type but not both. Occasionally one type of inflammatory bowel disease is diagnosed and with further testing or time the disease may be re-diagnosed as the other type.
Ulcerative colitis and Crohn’s disease differ primarily in the portions of the bowel that they each involve and also the layers of the bowel wall that are involved. Ulcerative colitis involves only the large bowel. It can involve a part of the large bowel only or the entire large bowel but it does not have “skip” areas. Skip areas are areas of the intestine that are normal with abnormal areas on either side of them. Ulcerative colitis only involves the innermost layer of the bowel (the lining of the bowel) known as the mucosa. It does not involve deeper layers of the bowel. Crohn’s disease on the other hand can involve any area of the gastrointestinal tract from the mouth to the rectum (the last portion of the colon) and the anus. Crohn’s disease involves not only the lining of the bowel, but can and usually does involve the deeper layers of the bowel. Even though Crohn’s disease can involve any portion of the gastrointestinal tract it typically does not involve every portion of the gastrointestinal tract. The most common sites of involvement are the end of the small intestine known as the terminal ileum, involved in up to 80% of patients, involvement in the colon in approximately 50% of patients, with approximately 5% of patients having disease in their stomach or first part of the small intestine known as the duodenum.
Both ulcerative colitis and Crohn’s disease are relatively uncommon problems in both children and adults. The incidence or number of new cases occurring each year appears to be increasing more for Crohn’s disease than for ulcerative colitis. In a group of approximately 100,000 children age 15 years or younger, it is estimated that approximately 2 or 3 of them will develop Crohn’s disease each year. However in a group of 100,000 children age 15-19, the rate of developing Crohn’s disease increases to 16 new cases per year. The chance of developing ulcerative colitis in childhood and adolescence is less than the chance of developing Crohn’s disease, with an incidence of 2 to 10 new cases per 100,000 populations per year. The teenage years are one of the most likely times for inflammatory bowel disease to be diagnosed. The other most common time is between 30-40 years of age.
Both ulcerative colitis and Crohn’s disease are more common in certain families. In large studies it has been shown that if someone has either ulcerative colitis or Crohn’s and all of their close family members (parents, grandparents, brothers, sisters and children) are followed for a period of thirty years there is a one in three chance of at least one other family member developing either ulcerative colitis or Crohn’s disease. The chance of a child or a sibling of a patient with IBD developing IBD is approximately 8%. If the original family member has ulcerative colitis the relative is likely to develop ulcerative colitis and if they have Crohn's disease the relative is likely to develop Crohn's. Neither ulcerative colitis nor Crohn’s disease are contagious, which means that you cannot catch it from your family member. The reason for family members being more likely to develop these diseases is probably due to inheriting a gene that makes an individual more susceptible to develop this type of inflammation of the bowel. In addition to being more common in certain families, both ulcerative colitis and Crohn’s disease are more common in certain ethnic groups, especially Jewish individuals of eastern European descent.
The most common symptoms of ulcerative colitis in children and teenagers are diarrhea, blood in the bowel movements and pain in the abdomen. Patients with this condition may have pain prior to a bowel movement that improves after a bowel movement, and frequent bowel movements up to 10 times per day or more. Patients may also feel that they need to have a bowel movement immediately or they are going to have an accident. Having bowel movements at night is not uncommon in patients with ulcerative colitis, especially when the colon is more inflamed. Other symptoms in children can include anemia (a low blood count), weight loss and poor growth, although the later two are more common with longstanding disease and more likely to occur with Crohn’s disease.
The symptoms of Crohn’s disease may be more subtle than those of ulcerative colitis or may be dramatic. Abdominal pain, diarrhea and weight loss are the most common symptoms occurring in 65-75% of patients. Poor growth is also common and a very important sign of pediatric Crohn’s disease. A child who is usually amongst the tallest in their class who becomes amongst the smallest, especially around the time of puberty may have Crohn’s disease. The average time between the first symptoms of Crohn’s disease and the diagnosis of Crohn’s disease may be up to a year due to the subtle first symptoms of Crohn’s disease. Fatigue or being tired due to anemia is common as is blood in the bowel movements, although less common than in ulcerative colitis. Up to 25% of patients will have disease around their bottom or anus; this may go unrecognized in a teenager who is uncomfortable discussing bowel issues with their parents or doctors. This includes extra folds of skin (skin tags), which may become inflamed, drainage of pus from small openings in the skin known as fistulas and fissures or cracks in the skin around the anus, which can be painful.
Although the stomach, small intestine and colon are the areas of the body that are most commonly involved with inflammatory bowel disease, patients can develop symptoms outside of the GI tract that are due to their inflammatory bowel disease. How severe the symptoms are may in some cases be related to how severe the bowel disease is or may be independent of the bowel symptoms. These symptoms are generally not due to medications administered for the bowel disease. The table below indicates some of the most common extraintestinal manifestations of inflammatory bowel disease.
|Symptom||Crohn’s disease||Ulcerative colitis|
|Joint swelling or pain/arthritis||yes||yes|
|Inflammation of the eye||yes||yes, but less common|
|Abnormal liver function tests/ liver disease||yes||yes|
|Inflammation of the pancreas||yes||uncommon except with meds|
|Bone disease||yes||yes, but less common|
After a careful history and physical examination your doctor can order blood work to screen for ulcerative colitis or Crohn’s disease. Blood work that would be abnormal in these conditions can include a blood count demonstrating anemia, especially if the iron level is low, an increased white blood cell count which may indicate inflammation or infection, an increased platelet count (the part of the blood that is responsible for helping blood clot), decreased blood levels of proteins such as albumin and an elevated sedimentation rate, or CRP value, nonspecific markers of inflammation. There are additional blood tests available that detect certain antibodies found more commonly in patients with inflammatory bowel disease. However, testing positive or negative for these antibodies does not establish or rule out the diagnosis of inflammatory bowel disease and therefore expert interpretation of these blood tests is required.
An x-ray called an upper GI with small bowel follow through can be obtained to look for irregularity in the small intestine. This is particularly helpful in pediatric patients, as the terminal ileum, which is the end of the small intestine, is the site most commonly abnormal in children with Crohn’s disease.
Endoscopy with biopsy (taking samples of tissue) also known as performing a scope test is the definitive way to diagnose inflammatory bowel disease and also to determine how much of the colon is involved. Colonoscopy, examining the colon as well as the end of the small intestine is the test most commonly performed in pediatric patients suspected of having either UC or Crohn’s disease. Endoscopy can also be performed of the stomach and first part of the small intestine in patients suspected of having Crohn's disease.
In addition, wireless capsule endoscopy can be used in pediatric patients suspected of having Crohn’s disease in whom the diagnosis is not established by upper endoscopy and colonoscopy, or in patients with a known diagnosis to establish how much of the small intestine is involved. This test is performed by having patients swallow a large capsule which takes video images as it travels through the digestive tract. Capsule endoscopy is most easily accomplished in older children and adolescents who can more readily swallow the capsule endoscope. This test should be avoided in children known or suspected to have a stricture of the intestines as this can cause the capsule to get stuck which may require surgery to remove it.
There are a variety of medications available to treat both ulcerative colitis and Crohn’s disease. Important pediatric considerations for medical therapy include long term side effects of the medications especially with regards to growth, bone disease such as osteoporosis (decreased calcium in the bone), development of cataracts in the eyes from medications such as steroids and a small risk of developing certain types of cancer with some medications or as a result of having chronic inflammatory bowel disease over a long period of time.
Medications used for pediatric patients with inflammatory bowel disease include the following:
|Types||How it is given|
|Aminosalicylate or 5-ASA products||by mouth, as a suppository or an enema|
|Steroids||by mouth, in the vein, or as an enema|
|Immunosuppressants (Imuran, 6-MP)||by mouth|
|Immunosuppressants (Methotrexate)||by mouth or by injection|
|Immunosuppressants (Cyclosporine)||by mouth or in the vein|
|Antibiotics||by mouth, in the vein|
|Immune-modulators (Infliximab, Adalimumab)||in the vein or by injection|
There are a variety of nutritional options also available for patients with Crohn’s disease and it has been shown that disease activity appears to decrease if patients are able to significantly increase their caloric intake through the use of standard or specialized diets. Supplementation with folic acid, calcium and Vitamin D in patients with decreased bone calcium is also helpful in pediatric patients with inflammatory bowel disease.
Colorectal surgery is curative for ulcerative colitis, but not for Crohn's disease. Surgery is usually performed for disease that does not get better despite medications, if severe medication side effects develop or for other complications of the underlying inflammatory bowel disease. Children undergoing removal of their colon for ulcerative colitis can have a pouch fashioned of small intestine that serves as a reservoir for stool and takes the place of the rectum. Children undergoing surgery for Crohn’s disease generally do so for development of a specific complication of their disease or their medication. Because Crohn’s disease always comes back following surgery given a long enough period of follow up, patients are usually continued on maintenance medications to cut down how quickly or how severely the disease comes back. Also the amount of bowel removed is limited in patients with Crohn’s disease in order to prevent additional problems with absorption of nutrients after surgery. Patients still require regular follow up with their gastroenterologist after surgery for either ulcerative colitis or Crohn’s disease.
The development of colon cancer appears to be a long term risk of having either ulcerative colitis or Crohn’s disease and in some cases appears to relate to the number of years of disease. (i.e. number of years following diagnosis) Disease starting in childhood may be a particular risk factor and therefore pediatric patients with both UC and Crohn’s disease require regular follow up with a gastroenterologist throughout their life to help reduce the risk of developing serious complications including colon cancer.
Marsha H. Kay, MD, The Cleveland Clinic, Cleveland, OH, and Annette E. Whitney, MD, Digestive Health Associates of Texas, Dallas, TX – Updated December 2012.
Marsha H. Kay, MD, The Cleveland Clinic, Cleveland, OH, and Vasundhara Tolia, MD, Children's Hospital Of Michigan, Detroit, MI – Published September 2004.