What is Crohn’s disease?
Crohn’s disease is one of the most common forms of inflammatory bowel disease (IBD). It is associated with inflammation of the digestive tract. The digestive tract runs from the mouth to the anus and includes the stomach and both small and large intestines. Inflammation can irritate deeper layers of digestive tissue as well as the lining.
What are the different types of Crohn’s disease?
The type of Crohn’s disease depends on the affected part of the digestive tract. The disease can also be classified by its severity. The most common areas that are involved are the terminal ileum (last part of the small intestine) and the colon (large intestine).
What causes Crohn’s disease?
Both genetic and environmental factors likely interact to cause Crohn’s disease. More than 200 different genes may affect the risk of Crohn’s disease. While limited information exists about the environmental causes of Crohn’s disease, living in a northern country (such as the United States, Canada, or northern Europe) and use of antibiotics in early life may increase risk of the disease.
How common is Crohn’s disease?
Crohn’s disease is common, and it affects people of all ages. In the United States, more than 1 million children and adults have either Crohn’s disease or ulcerative colitis. Some of the important risk factors for developing Crohn’s disease are:
- Family history of IBD
- Previous surgery to remove the appendix
- Maternal smoking
- Exposure to antibiotics early in life
Who develops Crohn’s disease?
Crohn’s disease can occur at any age, but it most often starts during adolescence. It rarely is seen in infants. The highest rates of Crohn’s disease are in white individuals with Jewish heritage.
What are the signs and symptoms of Crohn’s disease?
Your child may present with few or all of these symptoms:
- Abdominal pain – the pain may be in the lower right part of the abdomen, around the belly button or above the belly button. This pain may be persistent, severe, and could possibly wake your child from sleep.
- Diarrhea – passage of watery stool or frequent stool that is different from your child’s normal pattern. It could be mild to severe and may frequently wake your child from sleep.
- Constipation – in some cases, your child may have constipation, although this is usually in combination with other symptoms.
- Blood in the stool
- Weight loss
- Poor growth (not gaining height as quickly as expected or similarly to other children)
- Perianal disease (cracks or painful bumps in the anal area)
- Unexplained fevers
Other symptoms are referred to as extra-intestinal manifestations. These symptoms occur outside the digestive tract, including:
- Skin: Unusual skin rashes (may be called erythema nodosum or pyoderma gangrenosum)
- Joints: Pain and swelling of joints; ankylosing spondylitis (lower back pain, spine inflammation)
- Eyes: Inflammation of the white part or colored part (iris) of the eye (called uveitis, episcleritis, or iritis)
- Mouth: Oral sores (canker sores), which may range in severity from painless to severe and are usually recurrent
- Kidneys: Kidney stones; rarely, blood in the urine; kidney inflammation (called interstitial nephritis) can sometimes develop with Crohn’s disease or due to medication used to treat Crohn’s disease
- Bone: reduced bone mineral density and weak bones (called osteopenia), which may result from malnutrition, inadequate caloric intake or malabsorption, vitamin D deficiency, or excessive corticosteroid intake after Crohn’s disease diagnosis and which may result in increased risk of bone fracture
- Blood: anemia, which may result from iron, folate, or vitamin B-12 deficiency or may be caused by medications used to treat Crohn’s disease, such as 6-mercaptopurine or azathioprine
- Vessels: increased risk of blood clotting may occur, especially in children with active disease.
- Liver: inflammation of the liver may occur due to some rare associated conditions (autoimmune hepatitis, primary sclerosing cholangitis), or due to medications
- Pancreas: inflammation of the pancreas (called pancreatitis), which may develop as a reaction to drug therapy (6-mercaptopurine and sulfasalazine) or from unknown causes
Your primary care physician will perform an initial evaluation if you are concerned that you or your child has Crohn’s disease. Ask your doctor for referral to a pediatric gastroenterologist if your child has blood in the stool, persistent diarrhea, persistent abdominal pain, weight loss, poor growth, or pain/swelling around the anus.
How is Crohn’s disease diagnosed?
- Blood: Your doctor may collect blood to test for inflammatory markers, such as erythrocyte (red blood cell) sedimentation rates or C-reactive protein, as well as a complete blood count to test for high platelet levels (called thrombocytosis), low red blood cells (called anemia), or comprehensive metabolic panel [hypoalbuminemia (low protein) or abnormal electrolytes.
- Stool: Stool culture may be done to rule out bacterial infection in the gut. Markers of inflammation that can be identified in the stool (calprotectin or lactoferrin) may be tested.
- Imaging: The following imaging tests may be used to diagnose Crohn’s disease:
- Contrast studies, upper GI series with small bowel follow-through
- Abdominal computed tomography (CT) scan
- Magnetic resonance enterography (MRE) – this may be performed instead of a CT scan because CT scans expose the patient to radiation
- Ultrasound – while not commonly used to diagnose Crohn’s disease, it can used to monitor disease activity and response to treatment
- Endoscopy and colonoscopy: These are the main tests to confirm Crohn’s disease. Esophagogastroduodenoscopy (EGD) uses an endoscope to inspect the digestive tract, including the esophagus, stomach, and part of the intestines. Colonoscopy uses an endoscope, or tube with a camera, to inspect the colon and small intestine. Your child will need a clean-out (taking laxatives to empty the digestive tract of stool) before colonoscopy.
Video capsule endoscopy: This may be used to further assess the small intestine for any abnormalities. The capsule is a pill that can be either swallowed or placed with the endoscopy. The images from the camera are transmitted wirelessly to a recorder.
What is the treatment for Crohn’s disease?
Your doctor will discuss different therapies for Crohn’s disease depending on the severity. Your doctor may mention therapies for induction of remission (to make the symptoms disappear) or maintenance of remission (to prevent the symptoms from returning). Crohn’s disease treatment can include a combination of:
- Diet and nutrition
- Complementary therapy
Therapy for induction of remission for moderate to severe Crohn’s disease includes the following medications. Each medication has its own risks and benefits. Your gastroenterologist should review both the effectiveness and potential side effects in detail with you and your child.
Corticosteroids: prednisone, prednisolone, methylprednisolone, budesonide
These medications are used for a short time (a few weeks to a few months) to control symptoms. These medications are never stopped abruptly. Your doctor will tell you how to gradually reduce the dose to stop treatment. Because the body breaks down and processes these medications differently, some medications have significant side effects while others do not.
Aminosalicylates: sulfasalazine, mesalamine (brand names: Pentasa®, Asacol®, Lialda®, Apriso®), olsalazine, balsalazide
These are among the safest medications used to treat mild Crohn’s disease. These medications also have their own side effects but can be used long-term as maintenance treatment. They are usually ineffective for moderate to severe Crohn’s disease.
Antibiotics: metronidazole, ciprofloxacin (brand name: Cipro®)
Antibiotics are often used to treat infectious complications of Crohn’s disease, such as abscesses. These medications have anti-inflammatory properties and can be used to treat active Crohn’s disease. They are used for short periods and not for maintenance.
Immunomodulators: azathioprine (AZA) and 6-mercaptopurine (6MP)
These medications are primarily used as maintenance treatment in Crohn’s disease. They are used with other medications, such as biologics or aminosalicylates. They may also be used when your doctor is trying to discontinue corticosteroid use. These medications typically take 3–6 months to be effective.
Methotrexate is another immunomodulatory medicine used as a maintenance treatment for Crohn’s disease. This medicine typically takes 4 weeks to be effective.
Anti-tumor necrosis factor (TNF) agents or TNF inhibitors: infliximab (brand name: Remicade®), adalimumab (brand name: Humira®), golimumab (brand name: Simponi®), and certolizumab pegol (brand name: Cimzia®)
Anti-TNF agents are usually used in patients with moderate to severe IBD and are among the most effective treatments.
Anti-integrin agents: vedolizumab (brand name: Entyvio®), natalizumab (brand name: Tysabri®)
Anti-integrin agents are used in patients with Crohn’s disease who fail to respond to corticosteroids, immunomodulators, and anti-TNF agents. These medicines frequently take a longer time (months) to have an effect. Your doctor may sometimes add other medications during this waiting period.
Anti-interleukin agents: ustekinumab (brand name: Stelara®)
Anti-interleukin agents are usually used in Crohn’s disease patients who do not respond to corticosteroids, immunomodulators, and anti-TNF agents.
Biosimilars are biologics that are very similar to the original medication. They are not exact, but extremely close, so they aren’t called generics. Currently, biosimilars exist for Infliximab and soon adalimumab will have biosimilars. Insurance companies may request a switch to a biosmilar and this should be discussed with your healthcare provider. More information on Biosimilars can be found here.
Talk to your pediatric gastroenterologist about the therapy that is right for your child.
Diet and nutrition
Nutritional therapy may be suggested for your child as a primary treatment without medicines. It is very important if your child is suffering from malnutrition or poor weight gain. Nutrition therapy can also be used for induction and maintenance of remission.
Nutritional therapies can be given in the form of:
- Total parenteral nutrition: Nutrition given through the vein (intravenously) and bowel rest
- Enteral nutrition: Nutrition give either orally or through a naso-gastric (NG) tube (a dietitian will discuss different nutritional enteral formulas)
- Placement of gastrostomy tube: This may be indicated for long-term enteral therapy for those who do not want to use an NG tube
If nutritional therapy is suggested, your child’s doctor will discuss these options with you.
Alternative therapy is treatment for Crohn’s disease that is not traditional medical therapy. Complementary therapies are used in combination with traditional medicine.
Some research has been done on complementary and alternative therapies in people with CD. However, there is not enough research to determine if any of these therapies work. Discuss these options with your child’s gastroenterologist before starting any complementary/alternative therapies.
Herbal supplements: Echinacea, St. John’s Wort, Ginkgo, Garlic, Saw Palmetto
These are dietary supplements and are not recommended for active CD. Research has not proven if many plants can be used as medicines, especially not to treat IBD.
Probiotics: Saccharomyces boulardii, VSL#3, Lactobacillus rhamnosus GG
These supplements contain good bacteria that live in the human body. They work with the body to create an overall healthy environment. While commonly used by patients, and generally safe, there is no compelling evidence that they are effective.
Fish oil contains omega-3 fatty acids, which are essential to the human diet, along with omega-6 and omega-9. Omega-3 fatty acids may help with inflammation. Omega-3 fatty acids come from foods because our bodies do not produce these fatty acids. They can be obtained through foods such as fatty fish (salmon, herring, and mackerel) and some green vegetables.
Discuss with your doctor before starting any alternative/complementary therapy.
Surgery for Crohn's Disease
As with ulcerative colitis, a patient with Crohn’s disease may develop complications that require an emergency or urgent operation. In contrast to ulcerative colitis, any operation for Crohn’s disease carries a significant chance of disease recurrence and the need for further operations. Therefore, surgery for Crohn’s disease should not be considered a definitive cure.
However, there are still several scenarios in which surgery is the best decision for a child with Crohn’s disease. For example, occasionally there is a segment of bowel that is so diseased that it does not heal even with the strongest medications. In this instance, surgery is especially important if the diseased segment is affecting the child’s growth and development.
Additionally, once an area of bowel is significantly scarred (stricture), it is unlikely that any medications can improve the damage. This area of bowel may become narrowed and cause symptoms of bowel blockage (obstruction). Although patients with these types of complications may not need an emergency operation, they may not feel better until diseased areas of bowel are removed.
Surgical Indications for Crohn's Disease
- Uncontrollable bleeding
- Abscess or fistula
- Failure of medical therapy
- Perianal disease
Types of surgical procedures for Crohn’s disease:
This involves cutting the surface of the bowel over the stricture (narrowing), then sewing the bowel wall back together perpendicular to incision. This widens the bowel to allow easier passage of contents, although it does slightly shorten the bowel.
Limited bowel resection (removal of a diseased segment of bowel):
This generally involves removal of as little bowel as possible but enough to alleviate complications that the diseased segment of bowel was causing.
Bowel diversion with ostomy:
This involves re- directing the flow of stool through the bowel by cutting the intestine above the severely diseased bowel and bringing it to the skin surface through an ostomy. Stool then drains into a bag attached to the skin by adhesives rather than through the anus. This operation can allow severely diseased regions of bowel to heal and can be temporary or permanent.
Patients with Crohn’s disease may also need operations to drain collections of pus inside the abdomen (abscess) or to help treat abnormal connections (fistulae) between the bowel and other locations, such as other portions of bowel, bladder, vagina, or skin. These conditions can be especially problematic in the area around the anus (perianal disease). New non-surgical techniques are being developed to deal with treating fistulas.
Whenever an operation for a child or adolescent with IBD is considered, it is important to choose a surgeon who is familiar with the unique aspects of pediatric IBD care and with the various surgical techniques, including state-of- the-art advances in IBD surgery.
Numerous support organizations can provide valuable information on quality of life after surgery. Also, it may be beneficial for surgical candidates to talk to those who have undergone similar procedures. It is always advisable to make home care arrangements and address health insurance administrative issues before undergoing surgery
What are the complications of Crohn’s disease?
- Intestinal blockage and/or tearing
- Drug allergies and/or resistance
- Perianal disease
- Formation of an abnormal connection between organs (fistula)
- Abnormal narrowing of a body passage (stricture)
- Abscess within the abdomen and/or around the rectum (perirectal)
- Growth failure
What are possible outcomes of Crohn’s disease?
Although the disease may disappear (remission), it may come back later (recurrence). Often medication needs to be continued to maintain remission and keep a patient healthy. In many patients, remission can be achieved without steroids, but this usually requires the use of biologics (anti-TNF, vedolizumab, ustekinumab).
Some children may have more persistent inflammation, which requires intermittent to ongoing steroid treatment. Such cases require careful clinical evaluation and management to prevent complications.
Where can I find support for my child and family?
In addition to online resources, there are many community support groups. Ask your doctor or nurse about local community support groups, such as the Power of Two Program. Additional resources include the Crohn’s and Colitis Foundation, IBD Support Foundation, NASPGHAN Foundation, and ImproveCareNow.
Resources can also be found on our IBD Resources page.
Authors: Rebecca Cherry, MD, Laura Bauman, MD, Edwin F. de Zoeten MD, PhD
Editor: Athos Bousvaros, MD