Crohn's disease (CD) is a chronic condition characterized by patchy areas of inflammation and ulcers (open sores) along the innermost layer of the digestive tract. Such lesions can develop anywhere from the mouth to anus, but the majority of cases involve the small intestine or the first part of the large intestine. Between these patches of inflammation and ulceration there remain stretches of normal, healthy tissue.
CD is closely related to a similar condition known as ulcerative colitis (UC). Both CD and UC are considered inflammatory bowel diseases (IBD). CD affects between 2 and 7 out of 100,000 people and researchers believe that these numbers are growing. CD develops mostly between the ages of 15 and 40, although children and older adults may also develop the condition. People of Jewish heritage are up to six times more likely to develop CD than are people in the general population. Although medication and strict diets can reduce the inflammation of CD, most people with the condition will require surgery to remove part of the digestive tract at some point in their lives. Unfortunately, however, surgery does not completely cure or eradicate the disease.
Signs and SymptomsThe most common signs and symptoms of CD are diarrhea and abdominal pain. The symptoms can range from mild to severe.
- Diarrhea (with or without blood)
- Abdominal pain and bloating
- Poor appetite
- Weight loss
- Nausea and vomiting
- Floating stools (which is caused by poor digestion of fat)
CausesThere are many theories regarding the specific cause of CD, although none have been proven. It is most likely that a variety of factors work together to bring about the disease. These factors range from genetics, faulty immune system reactions, environmental influences, cigarette smoking, and perhaps diet. For example, some people are genetically at risk for CD (it runs in their family), and an infection or other toxin may cause an abnormal immune reaction which then causes CD.
- Jewish heritage (three to six times more likely than the general population)
- European (particularly Scandinavian) ancestry
- Family history of IBD
- Cigarette smoking
- Living in an industrialized country (particularly an urban area)
- Diet high in sugar and hydrogenated fat and low in fruit and vegetables
DiagnosisA healthcare practitioner will perform a thorough physical exam as well as a series of tests to diagnose CD. Blood tests may reveal anemia (due to a significant loss of blood) and a high white blood cell count (a sign of inflammation somewhere in the body). Stool samples may indicate whether there is bleeding or infection in the colon or rectum.
The following procedures may be used to diagnose CD. They are also helpful in distinguishing between ulcerative colitis, CD, and other inflammatory conditions.
- Endoscopic techniques (sigmoidoscopy and colonoscopy)—procedures in which an endoscope (a long, flexible, lighted tube connected to a computer and television monitor) is inserted into the anus to investigate the lining of the colon and rectum. A sigmoidoscopy is used to examine the rectum and the left colon (areas usually affected by ulcerative colitis) and can be conducted without sedation. A colonoscopy can reveal any inflammation, bleeding, or ulcers along the entire colon wall but this procedure usually requires sedation. Tissue samples (biopsies) may be taken from the colon wall for examination under a microscope in order to make a definitive diagnosis of CD.
- Barium X-ray—a patient swallows barium, which passes into the small intestine and shows up on an x-ray image. This image may reveal inflammation, ulcers, and other abnormalities in the intestinal wall.
- CT scans—this imaging technique is useful in diagnosing inflammatory bowel diseases such as CD and ulcerative colititis
Preventive CareAlthough there is no known way to prevent CD, the number of relapses can be reduced with the right combination of drug treatment, lifestyle changes, and nutrition. Studies show that a weekly injection of the drug methotrexate may help prevent recurrences. Exercise can help prevent the stress and depression that often accompany CD, and quitting smoking can reduce recurrences in those who use tobacco. Fish oil (which contains omega-3 fatty acids) and a bland diet also show promise as means of preventing relapse.
Treatment ApproachThe primary goal in treating CD is to control inflammation and replenish lost nutrients. The choice of treatment for CD depends on the severity of the disease. For example, people with mild to moderate CD are usually treated with medications that reduce swelling and suppress the immune response. More severe cases of CD may require surgery. In addition to medications, many people with inflammatory bowel diseases such as CD commonly turn to complementary and alternative remedies. Although these remedies still require extensive research, preliminary studies indicate that lifestyle changes, dietary adjustments (such as including a rich variety of fruits and vegetables and maintaining low levels of fat and sugar), specific herbs and supplements (such as turmeric) may be useful additions to drug treatment. Mind/body techniques (such as hypnosis and meditation) can help reduce stress associated with the disease.
At least one study has shown that IBD often begins within 1 year of a very stressful life event, such as the death of a family member. In addition, people with CD report that stress worsens their symptoms. Moreover, the anxiety associated with all of the potential consequences (such as the loss of bowel control) can also be very stressful. Therefore, relaxation techniques, such as yoga, tai chi, and meditation are worth considering, particularly when used in addition to other forms of treatment.
Exercise may also be helpful for those with CD. For example, one small study suggests that exercise increases the sense of satisfaction, decreases worrying, enhances energy, and lessens feelings of hopelessness in those with CD. Although exercise is generally considered safe for people with CD, those with the condition must take certain precautions when exercising and should talk to their healthcare practitioners before starting an exercise program. It is especially important for people with CD to drink one to two glasses of water before exercising and one glass of water every twenty minutes while exercising to prevent dehydration. Exercise should be avoided during symptom flare-ups or if the individual has a fever. Extreme fluctuations in body temperature during exercise should also be avoided.
Cigarette smoking is a risk factor for CD and studies have shown that it may worsen symptoms of the disease. Quitting smoking reduces the rate of symptom recurrence.
MedicationsMedications do not cure CD but they can significantly reduce symptoms of the condition. The following medications are commonly used to treat CD:
- Sulfasalazine — reduces inflammation during acute flare-ups; usually taken with folic acid; side effects include abdominal discomfort, nausea, and lowered sperm count
- Mesalamine — reduces inflammation during acute flare-ups and helps prevent recurrences
- Olsalazine and bulsalazide — reduces inflammation during acute flare-ups and helps prevent recurrences; has fewer side effects than sulfasalazine
- Corticosteroids (such as budesonide, prednisone, and prednisolone) — reduce inflammation by decreasing the production of prostaglandins (substances in the body that contribute to the development of pain and inflammation); corticosteroids are not effective for preventing recurrences; side effects (particularly over time) include acne, and an increased risk of infection, osteoporosis, high blood pressure, excessive hair growth, diabetes, and disorders of the eye including glaucoma and cataracts
- Medications that suppress the immune system (such as azathioprine, 6-mercaptopurine, cyclosporine, and methotrexate)—these medications decrease inflammation by suppressing the immune response; used when other drug therapies fail to improve symptoms or in combination with steroids to reduce the dose of the steroid medication
- Antibiotics (such as ciprofloxacin and metrondidazole) — may be prescribed for individuals who undergo surgical resection or have an excess accumulation of pus and bacterial overgrowth; side effects include nausea and anorexia
- Antidiarrheal medications (such as diphenoxylate, loperamide, or psyllium) — used for individuals with mild to moderate diarrhea. Medications used to treat diarrhea must be used only under medical supervision and with extreme caution; they can slow down the normal movements of the gastrointestinal tract and, in severe cases, may cause a complication known as toxic megacolon.
- Biological therapy — treatments designed to alter the immune response. This form of therapy often involves the use of agents called biological response modifiers (such as infliximab) and is used only in severe cases when other medications have failed to improve symptoms. Risks include development of infections such as tuberculosis.
Surgery and Other ProceduresAlthough surgical procedures will not cure CD, three out of four people with CD must eventually have resections (parts of their colons removed). Surgery may be required because of rupture of the colon; persistent fistulas (hollow passages running between loops of intestines and other organs such as the skin, bladder, or vagina) and abscesses (painful collections of pus, which can be caused by infected fistulas); and other problems caused by the disease. In some cases less invasive techniques may be used. For example, laproscopic procedures, in which the intestines are viewed and worked on through a small incision, allow for partial resection without extended hospital stays. Fibrous strictures (scar tissue that results in narrowing of the intestine) may be treated by a procedure called stricturoplasty, in which a "balloon" is inserted in the intestine and expanded.
Hyperbaric Oxygen Therapy (HBOT)
Several studies have suggested that HBOT may be a useful additional treatment for some people with CD. HBOT is a technique in which a person is given 100% oxygen at greater than normal pressure. The increased pressure raises the amount of oxygen being delivered to tissues, and this enhances the body's wound-healing abilities. This enhanced ability is particularly useful for people with CD in difficult-to-treat areas such as the anal region.
Nutrition and Dietary SupplementsPeople with CD are often malnourished and studies indicate that as many as 70% to 80% of individuals with this condition experience significant weight loss. This may occur because gastrointestinal discomfort, pain, and nausea make it difficult to eat or because a badly damaged or surgically shortened bowel prevents adequate nutrient absorption and digestion. Some medications are also thought to reduce stores of certain nutrients and vitamins in the body. For example, sulfasalazine lowers absorption of folate and corticosteroids can reduce levels of calcium. Ensuring adequate nutrition is therefore a crucial part of CD treatment. In most cases, dietary modification and supplements provide sufficient nutrition. People with significant malnourishment, severe symptoms, or those awaiting surgery may require total parenteral nutrition (nutrition maintained entirely by intravenous injection).
Preliminary evidence suggests that people who follow certain dietary patterns may be more likely to develop CD. For example, some studies indicate that low fruit and vegetable consumption and high fat and sugar consumption may increase an individual's risk for developing CD. Certain foods may also reduce symptoms and decrease the likelihood of recurrences. Studies suggest the following:
- Regular intake of fruits and vegetables, and lowered fat and sugar consumption may reduce the risk of developing CD.
- Certain foods may aggravate symptoms of CD (for example, dairy products, fats, spicy foods, and artificial sweeteners) and should be avoided by people with the condition.
- After surgery, people with CD should avoid foods high in organic acids known as oxalates (for example, spinach, rhubarb, black and blueberries, red currants, beets, celery, cucumbers, potatoes, coffee, tea, diet sodas, tofu, and chocolate) because oxalates can increase the risk of kidney stones.
- Elemental diets help prevent symptom recurrence and may be as effective as certain medications in treating CD. People with CD have difficulty digesting food and absorbing nutrients. Elemental formulas are "predigested," meaning that they contain only the basic building blocks of food and need not be broken down into smaller substances along the digestive tract. Unfortunately, some people find it difficult to adhere to an elemental diet because it carries certain food restrictions that may make it less appetizing. One study suggests that adding omega-3 fatty acids to an elemental diet may boost its nutritional content and thereby improve the likelihood that CD patients will adhere to it.
Because many people with CD have vitamin and mineral deficiencies (due to decreased nutritional intake and absorption by the colon, excessive diarrhea, and surgical resection of parts of the digestive tract), a multivitamin is often recommended by healthcare professionals. For example, several studies have found that people with CD have significantly lower levels of selenium, vitamins A, E, and various B vitamins. Further research is needed to determine whether specific vitamin or mineral supplements may help treat the symptoms of CD.
Vitamin B9 (Folate)
People with CD often have low levels of folate in their blood cells and some experts suggest that this may be due, at least in part, to sulfasalazine and/or methotrexate use. Other researchers speculate that folate deficiencies in CD patients may be due to decreased intake of folate in the diet and poor absorption of this nutrient. Folate deficiency may contribute to high levels of homocysteine, an amino acid that is thought to have a role in the development of certain chronic diseases. Further research is needed to determine the precise role of folate supplementation in people with inflammatory bowel disease.
People with CD often have low levels of vitamin D, which is needed to maintain healthy bones. In fact, bone loss in not an uncommon complication among people with CD. In one study, supplementation with vitamin D prevented bone loss in patients with CD, particularly in those whose vitamin D levels returned to normal.
Omega-3 Fatty Acids
Although studies overall have conflicting results, at least one study has found that, compared to placebo, fish oil supplements containing omega-3 fatty acids (namely EPA and DHA) may reduce symptoms of CD and prevent recurrence of the condition. Some experts suggest that measuring the blood levels of different types of fatty acids in people with CD may be necessary in order to determine if supplementation may be useful. Several studies also suggest that time release preparations may reduce the side effects commonly associated with this substance (such as flatulence and diarrhea).
Preliminary evidence suggests that N-acetyl glucosamine supplements or enemas may improve symptoms of CD in children with IBD who did not improve after using other treatments, but further research is needed to determine whether the substance is safe and effective for the treatment of CD.
Animal studies and preliminary human studies have found that probiotics, or "good" bacteria such as lactobacillus, may improve symptoms of CD and help prevent flare-ups. Further research is warranted.
Preliminary evidence suggests that there may be a role for zinc in changing the immune response of people with inflammatory bowel diseases, but further research is needed.
HerbsA professional herbalist may recommend one or more of the following herbs based on their chemical makeup and how they have been used in traditional medicine (particularly Ayurvedic and Traditional Chinese disciplines):
- Cat's claw (Uncaria tomentosa)—used by indigenous people in the Amazon as well as other regions of South America to treat intestinal disorders such as diarrhea, ulcers, and inflammatory bowel diseases
- Ginkgo (Ginkgo biloba)—contains substances that act as antioxidants and therefore, may protect the gastrointestinal tract from the damaging effects of CD
- Goldenseal (Hydrastis canadensis)—reduces the ability of bacteria to stick to the intestinal wall thereby protecting against CD; also has anti-inflammatory properties
- Green tea (Camellia sinensis)—has anti-inflammatory properties and may also reduce risk of cancer (a potential complication of CD)
- Salai guggal (Boswellia serrata)—this Ayurvedic herbal remedy has been compared to sulfazalazine for the treatment of ulcerative colitis; the medicine and the herb were considered equally effective but further studies for CD, specifically, are warranted
- Slippery elm (Ulmus fulva)—relieves gastrointestinal irritation
- Turmeric (Curcuma longa)—has anti-inflammatory and antioxidant properties, and reduces the possibility of cancerous changes in cells; used to treat digestive disorders in Ayurvedic and Traditional Chinese Medicine traditions
- Wild indigo (Baptisia tinctoria)—contains substances that act as antioxidants; also has properties that protect against infection and reduce inflammation
HomeopathyAlthough few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of Crohn's disease symptoms (such as diarrhea) based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. A constitutional type is defined as a person's physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.
- Mercurius—for foul-smelling diarrhea that may have streaks of blood accompanied by a sensation of incomplete emptying; this remedy is most appropriate for individuals who tend to feel exhausted following bowel movements, experience fluctuations in body temperature, perspire frequently, and have a thirst for cold fluids
- Podophyllum—for explosive, gushing, painless diarrhea that worsens after eating or drinking; exhaustion often follows bowel movements and the individuals for whom this remedy is appropriate may experience painful cramps in the lower legs and feet
- Veratrum album—for profuse, watery diarrhea accompanied by stomach cramps, bloated abdomen, vomiting, exhaustion, and chills; the diarrhea tends to worsen as a result of eating fruit; the individual for whom this therapy is appropriate tends to crave cold liquids
Mind/Body MedicineHypnosis and Other Relaxation Techniques
Studies suggest that hypnosis may improve immune function, increase relaxation, decrease stress, and ease feelings of anxiety. Many healthcare practitioners and people with CD have reported that symptoms of the disease improve with relaxation methods such as hypnosis, meditation, and biofeedback.
Some people with CD suffer from depression and anxiety and may be referred to a psychiatrist or psychologist for appropriate care.
PregnancyWomen who are in remission at the time of conception generally have normal pregnancies and healthy babies. However, women with active disease are more prone to miscarriages, spontaneous abortions, and stillbirths. The disease often worsens during pregnancy. For this reason, women with active CD who are or wish to become pregnant should continue maintenance therapy under the guidance of their healthcare practitioner. Corticosteroids or sulfasalazine are considered relatively safe during this time.
Pregnant women should avoid high doses of vitamins. An obstetrician can provide instructions regarding appropriate multivitamin use during pregnancy. The herbs cat's claw (Uncaria tomentosa), goldenseal (Hydrastis canadensis), and turmeric (Curcuma longa) are not recommended during pregnancy. Women who are breastfeeding should also avoid cat's claw and goldenseal.
Warnings and PrecautionsPeople with CD should avoid herbs that loosen the bowels. These include:
- Buckthorn bark (Rhamnus frangula)
- Cascara sagrada bark (Rhamnus purshiana)
- Senna leaf and senna pod (Senna alexandrina)
- Milk (and milk products)
- Spicy foods
- Sugars and artificial sweeteners
- Spinach, kale, greens (collards, dandelion, mustard)
- Rhubarb, blackberries, blueberries, and red currants
- Green beans, beets, celery, cucumbers, eggplant, okra, green peppers, sweet potatoes, rutabagas, summer squash
- Diet sodas
- Chocolate and cocoa, chocolate milk
Prognosis and ComplicationsA wide range of complications can develop from CD, some of which are listed below. Fortunately, however, many can be successfully treated.
- Narrowing of the colon, which may cause obstruction
- Perforation of the colon
- Abscesses (pus-filled pockets of infection) in the colon
- Toxic megacolon (grossly swollen colon that may rupture)
- Fistulas (an abnormal passageway such as an opening near the anus)
- Infection of the blood (called sepsis)
- Colon cancer
- Nutritional problems (including weight loss and reduced muscle mass)
- Joint pain and arthritis (such as ankylosing spondylitis)
- Bone loss which can result in osteoporosis
- Gallstones and other damage to the biliary system
- Skin rashes
- Eye infections/inflammation
- Mouth ulcers, gum inflammation, and dental cavities
- Liver damage
- Blood clots
- Depression and anxiety
- Menstrual irregularities
- Sexual dysfunction including pain with intercourse and diminished sexual desire
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