The Crohn’s disease is a chronic inflammatory disease of the digestive system, which evolves in spurts (or seizures) and remission stages. It is mainly characterized by attacks of abdominal pain and diarrhea, which can last several weeks or months. Fatigue, weight loss and even undernutrition can occur if no treatment is undertaken. In some cases, non-digestive symptoms that affect the skin, joints or eyes may be associated with the disease.
In Crohn’s disease, inflammation can affect any part of the digestive tract, from the mouth to the anus. But most often, it settles at the junction of the small intestine and the colon (large intestine) (see diagram).
|Crohn’s disease or ulcerative colitis?
The Crohn’s disease was first described in 1932 by an American surgeon, Dr. Burrill B. Crohn. It is similar in many ways to ulcerative colitis, another common inflammatory condition of the intestine. To distinguish them, doctors use different criteria. The ulcerative colitis affects only a segment delimited rectum and colon. For its part, Crohn’s disease can reach other parts of the digestive tract, from the mouth to the intestines (sometimes leaving healthy areas). Sometimes it is not possible to distinguish these two diseases. The condition is called “indeterminate colitis”.
In Canada, Crohn’s disease affects about 50 people per 100,000 populations in industrialized countries, but there is great variability across geographic regions. The most reported place in the world is in Nova Scotia, a Canadian province, where the rate rises to 319 per 100,000 people. In Japan, Romania and South Korea, the rate is less than 25 per 100,000.
The disease can occur at any age, including childhood. It is usually diagnosed tasks people 10 to 30 years.
Causes of Crohn’s disease
The Crohn’s disease is due to a persistent inflammation of the walls and the deep layers of the digestive tract. This inflammation can lead to thickening of the walls in some places, cracks and sores to others. The causes of inflammation are unknown and likely multiple, involving genetic, autoimmune and environmental factors.
Genetic factors. Although Crohn’s disease is not an entirely genetic disease, some genes may increase the risk of developing it. In recent years, researchers have discovered several susceptibility genes, including the NOD2 / CARD15 gene, which increases the risk of disease by 4 or 5. This gene plays a role in the body’s defense system. However, other factors are necessary for the disease to occur. As in many other diseases, it seems that a genetic predisposition combined with environmental or lifestyle factors triggers the disease.
Autoimmune factors. Like ulcerative colitis, Crohn’s disease has features of autoimmune disease . Researchers believe that inflammation of the digestive tract is linked to an excessive immune response by the body against viruses or bacteria in the gut.
Environmental factors. Note that the incidence of Crohn’s disease is higher in the industrialized countries and tends to increase since 1950. This suggests that environmental factors, probably related to the Western way of life, could have an important influence on the appearance of the disease. However, no specific factor has yet been detected. Several tracks are however under study. Exposure to certain antibiotics, particularly the tetracycline class, is a potential risk factor. Smokers are at higher risk of developing the disease. Too sedentary people are more affected than people who are more active.
It is possible, but there is no absolute proof that the rich too bad fat diet, meat and sugar increase the risk. It has long been thought that stress can trigger crises. However, studies to date seem to refute this hypothesis.
The researchers focus on the possible role of infection by a virus or bacteria (salmonella, campylobacter) in the onset of the disease. In addition to infection by “outside” microbe, an imbalance of intestinal flora (that is to say bacteria naturally present in the digestive tract) could also be involved.
In addition, some elements seem to have a protective effect. It is a diet rich in fiber and fruit, contact with cats or farm animals before the age of one, appendectomy, and gastroenteritis or infections. Respiratory. There is also no association between MMR (measles-rubella-mumps) and Crohn’s disease.
Evolution of the disease
It is a chronic disease that is present throughout life. Most often, Crohn’s disease evolves through periods of remission that can last for several months. About 10% to 20% of people have sustained remission after the first outbreak of the disease. The recurrences (or crises) follow one another in a rather unpredictable way and are of variable intensity. Sometimes the symptoms are so intense (inability to eat, haemorrhage, diarrhea, etc.) that hospitalization becomes necessary.
Complications and possible consequences
The Crohn’s disease can cause various health problems. The severity of symptoms and complications, however, varies greatly from person to person.
- An obstruction of the digestive tract. Chronic inflammation may result in thickening of the lining of the digestive tract, which may lead to partial or complete blockage of the digestive tract. This can lead to bloating, constipation, or even vomiting of faeces. Emergency hospitalization may be necessary to prevent perforation of the bowel.
- Of ulcers in the gut wall.
- Wounds around the anus (fistulas , deep fissures or chronic abscesses).
- Hemorrhages of the digestive tract, rare but sometimes serious.
- People with Crohn’s disease in the colon have a slightly increased risk of getting colon cancer, especially after several years of illness, and even if they are in treatment. It is therefore advisable to have early and regular detection of colon cancer.
- A malnutrition because during crises, patients tend to eat less because of pain. In addition, the ability to absorb food through the wall of the intestine is compromised, in medical language we speak of malabsorption.
- A stunted and puberty in children and adolescents.
- Iron deficiency anemia, due to bleeding in the digestive tract, which can occur with low noise and be invisible to the naked eye.
- Other health problems, such as arthritis, skin conditions, eye inflammation, mouth ulcers, kidney stones or gallstones.
- Crohn’s disease, when in the “active” phase, increases the risk of spontaneous abortion in pregnant women who have it. It can make the growth of the fetus difficult. It is therefore important that women who wish to become pregnant control their disease very well with the help of treatments and discuss it with their doctor.
The symptoms of Crohn’s disease
The Crohn’s disease can affect any part of the digestive tract. The symptoms (and their intensity) vary from case to case.
- Frequent abdominal pain and cramps, which increase after meals.
- Chronic diarrhea (lasting more than 2 weeks)
- Fatigue and general discomfort.
- Low appetite and weight loss, even with a balanced diet.
- Blood in the stool, sometimes in large quantities (hemorrhages).
- Moles in the stool. The mucus is a thick, spinning mucus with the consistency of an egg white.
- Nausea and vomiting.
- A slight fever (38ºC to 40ºC).
- Pain in the joints.
People at risk and risk factors for Crohn’s disease
People at risk
- People with a family history of inflammatory bowel disease (Crohn’s disease or ulcerative colitis). This would be the case for 10% to 25% of sufferers.
- Some populations are at higher risk than others because of their genetic heritage. The Jewish community (of Ashkenazi origin), for example, would be 4 to 5 times more affected by Crohn’s disease.
- Smoking increases the risk of developing Crohn’s disease.
Prevention of Crohn’s disease
|Can we prevent?|
|Since we do not know precisely the causes of the disease, no way to prevent it is known.
A study published in 2010, conducted among more than 67,000 women in France, however, showed that a high consumption of animal protein (meat and fish) was associated with an increased risk of suffering from the disease. These data remain to be confirmed for men and children.
|Measures to prevent aggravation and recurrence|
|Follow the treatment to the letter. The treatment, if it is adapted and well followed, makes it possible to reduce the frequency of the attacks and to prevent aggravation of the lesions.
Do not smoke. Smoking, even mild, increases the intensity of symptoms, the number of recurrences and surgical procedures related to the disease.
Avoid over-the-counter or over-the-counter anti-inflammatory medications (see list in Treatments section below). These are contraindicated because they can trigger a seizure or worsen the symptoms. As a painkiller, favor acetaminophen. At the recommended doses, acetaminophen (Tylenol) is safe for the digestive system.
Power. Several studies have examined the utility of various dietary changes to prevent recurrence. Some have tested the effect of reduced intake of refined sugars and increased Omega-3. Others have tested the exclusion of certain foods. These experiments, however, did not reveal a particular diet that would prolong the duration of remission periods in the majority of patients.
In some cases, however, it appears that some foods make the symptoms worse, but these foods vary from person to person. This may be red meat, cereals (wheat or maize), dairy products, certain fruits or vegetables, etc.It is recommended that each person discover these foods, for example in a notebook noting the composition of meals and intensity of symptoms after each meal. Some doctors suggest exclude food “triggers” for 2 to 4 weeks to see if symptoms improve or not. Indeed, reactions to food are not necessarily immediate.
Medical treatments for Crohn’s disease
There is no cure for Crohn’s disease. The goal of treatment is to correct food deficiencies and control inflammation, which will help relieve pain, diarrhea and other symptoms. During periods of remission, it is often necessary to follow a maintenance treatment to reduce the frequency of relapses and limit the progression of lesions. In the majority of cases, it should be emphasized that current treatments can control the disease well.
|Since the disease progresses with periods of remission, it is sometimes difficult for the physician to evaluate the effectiveness of the treatments. To better judge the effectiveness of a treatment, it is therefore recommended to keep a diary where we note daily:
– The number of stools;
These are the treatments prescribed in the first line to calm inflammation in a crisis. The choices of the drug and its route of administration depend on the intensity of the symptoms and their location in the digestive system.
- Aminosalicylates (or salicylates), including sulfasalazine (Azulfidine) and mesalazine or mesalamine (Rowasa, Canasa, Asacol Pentasa, Apriso, Lialda, Mezavant) are administered orally, rectally ( suppositories) or by enema. They are used both to calm relapses and to maintain remission. The most common side effects are nausea, vomiting and headache.
- If intestinal aminosalicylates are not enough to relieve symptoms, the doctor suggests more powerful anti-inflammatory drugs, such as oral corticosteroids , which have a general anti-inflammatory effect. The most commonly prescribed corticosteroids for Crohn’s disease are prednisone and prednisolone. They are usually used for a few weeks, until remission is obtained. The dose is then gradually decreased. In some cases where the disease is localized and moderately active, budesonide, a corticosteroid that acts locally in the digestive tract, with fewer side effects, can be proposed.Oral corticosteroids with systemic effects, however, have risks of adverse effectsmore marked, which limit their long-term use. These include weight gain, acne, increased hair growth, mood disorders and insomnia. In the long term, corticosteroids can also induce osteoporosis.
Immunomodulators and biotherapies
The immunomodulators (including immunosuppressants ) act very selectively on certain players of the immune system to calm the inflammatory reactions. These drugs are generally used to maintain remission after “attack” treatment with aminosalicylates or corticosteroids. They also help to cure fistulas. 6-mercaptopurine (6-MP, Purinethol) and azathioprine (Imuran) are the most commonly prescribed immunomodulators for people with Crohn’s disease. Methotrexate (Rheumatrex) can also be used. These medications can cause side effects (nausea, vomiting, diarrhea) and decrease resistance to infections if the dose is adjusted incorrectly.
The anti-TNF-alpha agents , such as infliximab (Remicade) and adalimumab (Humira), are recent drugs that target the tumor necrosis factor ( TNF ), a substance play a role in inflammation. These medications are reserved for patients who have moderate to severe symptoms and for whom other medications are ineffective or cause too much side effects. They can also be used as maintenance treatments.
Some antibiotics may be prescribed in cases of sudden worsening of symptoms caused by an intestinal infection. Antibiotics can also treat abscesses and wounds in the anal area.
In some cases, antidiarrheals may help reduce diarrhea. In particular, psyllium or methylcellulose makes it possible to regulate the transit. However, antidiarrheals or laxatives can also irritate the digestive tract and cause serious complications in people with inflammatory bowel disease. It is imperative to seek the advice of your doctor before taking any antidiarrheal, antispasmodic or laxative, whatever it is.
Iron supplements, to be taken orally, may be necessary in case of anemia.
The analgesics relieve mild abdominal pain. Favor acetaminophen (Tylenol).
|Important: Non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Advil, Motrin) or naproxen (Aleve) are contraindicated in people with Crohn’s disease because they may aggravate symptoms or trigger an acute attack.|
During crises. To relieve discomfort, it is advisable to reduce the consumption of dietary fiber (baked goods to whole wheat flour, several fruits and vegetables raw or unpeeled, etc.). Note that these foods have no adverse effect per se on the digestive tract. But the dietary fiber, by increasing the volume of the stools, put pressure on the inflamed wall of the intestines, which has the consequence of increasing the digestive disorders. When the crisis fades, these restrictions are no longer necessary.
Ask your doctor, a nutritionist or a patient association to find out what kind of foods you should useduring your seizures.
Support food. Although this is rare, it can happen that the irritated bowel can no longer absorb nutrients properly. To avoid undernutrition, it is then possible to inject nutritive solutions intravenously(parenteral nutrition). These are supplements of vitamin complexes and minerals and highly caloricliquid preparations . This avoids deficiencies , including protein, vitamins (A, folic acid, B12, C, D, E and K) and minerals (calcium, copper, iron, magnesium, selenium and zinc). The person can resume a normal diet as soon as the attenuation of symptoms allows.
A surgery is sometimes necessary, especially if complications (fistulas, complete obstruction of the gastrointestinal tract or perforated ulcer). If a section of the digestive tract is damaged by inflammation, it is possible to remove this section by surgery and then connect the two ends together. Surgery can therefore treat some complications, but the disease remains present.