Crohn's Disease

What is Crohn's disease?

From: MedlinePlus, National Library of Medicine

Crohn's disease is a chronic (long-lasting) disease that causes inflammation in your digestive tract. It can affect any part of your digestive tract, which runs from your mouth to your anus. But it usually affects your small intestine and the beginning of your large intestine.

Crohn's disease is an inflammatory bowel disease (IBD). Ulcerative colitis and microscopic colitis are other common types of IBD.

What causes Crohn's disease?

From: MedlinePlus, National Library of Medicine

The cause of Crohn's disease is unknown. Researchers think that an autoimmune reaction may be one cause. An autoimmune reaction happens when your immune system attacks healthy cells in your body. Genetics may also play a role, since Crohn's disease can run in families.

Stress and eating certain foods don't cause the disease, but they can make your symptoms worse.

Who is more likely to develop Crohn's disease?

From: MedlinePlus, National Library of Medicine

There are certain factors that may raise your risk of Crohn's disease:

• Family history of the disease. Having a parent, child, or sibling with the disease puts you at higher risk.
• Smoking. This may double your risk of developing Crohn's disease.
• Certain medicines, such as antibiotics, birth-control pills, and nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen. These may slightly increase your chance of developing Crohn's.
• A high-fat diet. This may also slightly increase your risk of Crohn's.

What are the symptoms of Crohn's disease?

From: MedlinePlus, National Library of Medicine

The symptoms of Crohn's disease can vary, depending where and how severe your inflammation is. The most common symptoms include:

Some other possible symptoms are:

Stress and eating certain foods such as carbonated (fizzy) drinks and high-fiber foods may make some people's symptoms worse.

• Diarrhea
• Cramping and pain in your abdomen
• Weight loss
• Anemia, a condition in which you have fewer red blood cells than normal
• Eye redness or pain
• Fatigue
• Fever
• Joint pain or soreness
• Nausea or loss of appetite
• Skin changes that involve red, tender bumps under the skin

What other problems can Crohn's disease cause?

From: MedlinePlus, National Library of Medicine

Crohn's disease can cause other problems, including:

• Intestinal obstruction, a blockage in the intestine
• Fistulas, abnormal connections between two parts inside of the body
• Abscesses, pus-filled pockets of infection
• Anal fissures, small tears in your anus that may cause itching, pain, or bleeding
• Ulcers, open sores in your mouth, intestines, anus, or perineum
• Malnutrition, when your body does not get the right amount of vitamins, minerals, and nutrients it needs
• Inflammation in other areas of your body, such as your joints, eyes, and skin

How is Crohn's disease diagnosed?

From: MedlinePlus, National Library of Medicine

Your health care provider may use many tools to make a diagnosis:

• A medical history, which includes asking about your symptoms
• A family history
• A physical exam, including: Checking for bloating in your abdomen. Listening to sounds within your abdomen using a stethoscope. Tapping on your abdomen to check for tenderness and pain and to see if your liver or spleen is abnormal or enlarged.
• Various tests, including: Blood and stool tests. A colonoscopy. An upper GI endoscopy, a procedure in which your provider uses a scope to look inside your mouth, esophagus, stomach, and small intestine. Diagnostic imaging tests, such as a CT scan or an upper GI series. An upper GI series uses a special liquid called barium and x-rays. Drinking the barium will make your upper GI tract more visible on an x-ray.

What are the treatments for Crohn's disease?

From: MedlinePlus, National Library of Medicine

There is no cure for Crohn's disease, but treatments can decrease inflammation in your intestines, relieve symptoms, and prevent complications. Treatments include medicines, bowel rest, and surgery. No single treatment works for everyone. You and your provider can work together to figure out which treatment is best for you:

Changing your diet can help reduce symptoms. Your provider may recommend that you make changes to your diet, such as:

In some cases, your provider may ask you to go on a special diet, such as a diet that is:

If you are not absorbing enough nutrients, you may need to take nutritional supplements and vitamins.

• Medicines for Crohn's include various medicines that decrease the inflammation. Many of these medicines do this by reducing the activity of your immune system. Certain medicines can also help with symptoms or complications, such as nonsteroidal anti-inflammatory drugs and anti-diarrheal medicines. If your Crohn's causes an infection, you may need antibiotics.
• Bowel rest involves drinking only certain liquids or not eating or drinking anything. This allows your intestines to rest. You may need to do this if your Crohn's disease symptoms are severe. You get your nutrients through drinking a liquid, a feeding tube, or an intravenous (IV) tube. You may need to do bowel rest in the hospital, or you may be able to do it at home. It will last for a few days or up to several weeks.
• Surgery can treat complications and reduce symptoms when other treatments are not helping enough. The surgery will involve removing a damaged part of your digestive tract to treat: Fistulas Bleeding that is life threatening Intestinal obstructions Side effects from medicines when they threaten your health Symptoms when medicines do not improve your condition
• Avoiding carbonated drinks
• Avoiding popcorn, vegetable skins, nuts, and other high-fiber foods
• Drinking more liquids
• Eating smaller meals more often
• Keeping a food diary to help identify foods that cause problems
• High calorie
• Lactose free
• Low fat
• Low fiber
• Low salt

Genetic causes described in the linked summary

From: MedlinePlus Genetics

The causes of Crohn's disease are complex. This condition results from a combination of genetic, environmental, and lifestyle factors, many of which are unknown.

Many of the major genes related to Crohn's disease, including NOD2, ATG16L1, IL23R, and IRGM, are involved in immune system function. The proteins produced from these genes help the immune system sense and respond appropriately to bacteria in the lining of the digestive tract. Many of the proteins play roles in autophagy, which is a process that cells use to surround and destroy bacteria and viruses. Variations in these genes may disrupt autophagy or otherwise alter the immune system's response to bacteria in the digestive system. In combination with other genetic and environmental factors, these changes can lead to chronic inflammation and result in the digestive problems characteristic of Crohn's disease.

Researchers have identified at least 200 genetic variations that influence Crohn's disease risk. The majority of these variations are thought to act by subtly changing the amount, timing, and location of gene activity (expression). The mechanism by which many of the variations influence disease risk is unknown, although they probably alter immune system function in some way. Considered together, the known genetic variations account for only a small percentage of the total Crohn's disease risk that is due to genetic factors.

Environmental and lifestyle factors likely have a large impact on Crohn's disease risk. Studies have found that cigarette smoking doubles the likelihood of developing this disease, and it may also play a role in periodic flare-ups of signs and symptoms. Crohn's disease is more prevalent in urbanized societies, suggesting that factors related to increased industrialization and sanitation also play a role. Additionally, certain aspects of a person's diet, including sugar, fats, and fiber, have been proposed to influence Crohn's disease risk. Many of the potential lifestyle and environmental risk factors are probably related, directly or indirectly, to abnormal inflammation. However, the exact relationship between these factors and Crohn's disease risk remains unclear.

Inheritance described in the linked summary

From: MedlinePlus Genetics

The inheritance pattern of Crohn's disease is unclear because many genetic and environmental factors are likely to be involved. However, Crohn's disease tends to cluster in families; about 15 percent of affected people have a first-degree relative (such as a parent or sibling) with the disorder.

Which doctor should you see?

The suggested department for discussing Crohn's Disease is Gastroenterology, with a gastroenterologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which digestive symptoms or nutritional changes matter most?
• What question would an endoscopy, scan or laboratory test answer if one is proposed?
• How should persistent pain, bleeding or difficulty eating be followed up?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.