Crohn's disease is an inflammatory bowel disease and can have both short and long-term effects. It causes symptoms such as diarrhoea and abdominal pain. Crohn's disease is a mild condition for some people, for others it may be severe.
Crohn's disease is inflammation of the wall of your digestive system, from your mouth down through your stomach and bowel to your anus. However, it's most common in your small bowel or the first part of your large bowel. It may affect more than one area and leave unaffected areas in-between.
If you have Crohn's disease, you will have inflammation and swelling in affected areas of your bowel and ulcers may form. These are similar to mouth ulcers and cause raw areas of the lining of your bowel, which can bleed. Your bowel wall can become thickened and this may cause blockages.
Crohn's disease mostly affects young adults, although older people can also develop it. It can also run in families; about one in five people with the condition will have a family member who also has it.
Crohn's disease isn't caused by an infection and can't be caught from someone else.

Crohn's disease is a chronic illness. This means that it lasts for a long time, sometimes for the rest of the person's life. The term chronic refers to how long a person has the illness, not to how serious a condition is.
The symptoms of Crohn's disease can be unpredictable, with periods of time when the condition flares up, when the disease is said to be active, and periods of time when there are few or no symptoms at all. The period when you have no symptoms is called remission. Usually there's nothing obvious that triggers the symptoms coming back (a relapse).
Symptoms include:
Active Crohn's disease may cause other problems such as:
With severe, long-term inflammation, you may develop complications. The main complications are:
If you have Crohn's disease that affects your colon, you will have a higher risk of developing bowel cancer. One in 20 people with Crohn's disease will develop bowel cancer in the 10 years after their condition is diagnosed.
The reasons why you may develop Crohn's disease aren't fully understood. It's thought that you're more likely to have Crohn's disease if you have a reaction between your immune system and certain bacteria in your bowel. For some people, Crohn's disease may be inherited and passed down through families.
There are certain lifestyle factors that make developing Crohn's disease more likely, for example, smoking. The role of certain foods isn't fully understood. However, it's possible that you're more likely to develop the condition if you eat only a small amount of fruit and vegetables.
Your GP will ask about your symptoms and examine you. They may also ask you about your medical history. You may be referred to a gastroenterologist, a doctor who specialises in identifying and treating conditions of the digestive system. You may have a number of tests including:
These tests usually take place as out-patient procedures. This means you have the test in hospital, but you won't need to stay overnight.
There's no cure for Crohn's disease but your symptoms can be controlled.
There's no special diet for managing Crohn's disease but it's important that you eat healthy, balanced meals. However, if you have any blockages in your bowel which cause abdominal pain, you may want to eat foods that are low in fibre. This is called a low-residue diet. When your Crohn's disease is active, your doctor may recommend that you have a liquid diet, made up of simple forms of protein, carbohydrates and fats. This is called an elemental diet, and helps your bowel to rest and reduces inflammation.
Some people believe that fish oil supplements can help reduce the number of flare-ups of Crohn's disease, though this has not yet been proven.
Medicines are the most effective treatment for most people with Crohn's disease. Commonly used medicines are listed below.
If you have severe Crohn's disease and have tried other treatments that haven't worked, your doctor may suggest medicines called tumour necrosis factor (TNF) inhibitors. Examples of these are infliximab and adalimumab.
If you need to take painkillers, avoid non-steroidal anti-inflammatory medicines (NSAIDs), such as ibuprofen. These can cause a flare-up of Crohn's disease. It's usually fine to take paracetamol as a painkiller, but check with your doctor first.
Eight out of 10 people with Crohn's disease may need to have an operation at some time. If you have a blockage or your bowel has become thickened, then you may need an operation to remove part of your bowel or to widen it. Surgery may also help if medicines aren't able to control your condition.
When you're in remission with few or no symptoms, then you will probably find that Crohn's disease has little impact on your day-to-day life. However, when your condition flares up, your symptoms can make life more difficult. Symptoms such as diarrhoea and abdominal pain may mean you need to take time off work.
Once you start treatment for a flare-up, you should find that your symptoms will improve, usually after a few days or weeks.
Crohn's & Colitis Australia
www.crohnsandcolitis.com.au
Gastroenterological Society of Australia
www.gesa.org.au
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