Crohn’s disease is a condition where the intestines become inflamed (red and swollen) and ulcerated (open sores that may bleed). Crohn’s disease can occur in any part of the gastrointestinal tract, from mouth to anus, often in a patchy distribution with sections of normal gut in between. It is one of the two main forms of Inflammatory Bowel Disease (IBD). The other is Ulcerative Colitis. Crohn’s disease is a chronic condition. This means that is ongoing and life-long, although it can be managed effectively, especially with the use of medication to control the inflammation,
The exact cause of Crohn’s disease is not known. It is thought to be an autoimmune disorder. In people who are genetically predisposed, the immune system becomes overactive against the bowel (possibly the bacteria in the bowel). This could be triggered by environmental triggers like smoking, food-poisoning or the use of some anti-inflammatory medications like ibuprofen. The overactive immune response then causes the inflammation in the intestines causing the symptoms of IBD.
The most common symptoms of Crohn’s disease are:
- Abdominal cramps and pain
- Frequent diarrhoea (may be bloody) or sometimes constipation
- Weight loss
- Tiredness and fatigue
- Sores around the anus (Perianal abscesses and fistulae)
Some people also experience problems outside the gastrointestinal tract such as:
- Joint pain – this can affect one in three people with Crohn’s
- Skin conditions
- Eye Inflammation
- Liver disorders (rare)
- Thinning of the bones (osteoporosis)
Crohn’s disease affects different people in different ways, with some having more severe symptoms and others no symptoms at all. It is highly individual and depends on:
- Where the disease is located within the bowel
- If there is active inflammation or not
- How severe the inflammation is
In most people the disease tends to run through periods of remission with episodes of flare-ups.
Diagnosis of Crohn’s Disease
A variety of tests may be needed to make a diagnosis of Crohn’s disease, these include:
- Blood tests – to check inflammatory markers
- Endoscopy and Colonoscopy – to examine the upper gastrointestinal tract and the colon as well as the last part of the small bowel joining the colon called the terminal ileum.
- MRI Enterography – this is a specialised MRI to examine the small bowel which is not easily reached by colonoscopy
- Intestinal ultrasound – this is a non-invasive tool to examine the small bowel for inflammation – this is often used in conjunction with MRI and colonoscopy for ongoing monitoring
Complications of Crohn’s Disease
Crohn’s can cause additional health problems, which may be in the gut itself or can involve other parts of the body. These include strictures, perforations and fistulas. A variety of other health conditions can be associated with Crohn’s Disease, including anaemia (reduced level of red blood cells), blood clots (including deep vein thrombosis), anxiety and depression.
Treatment of Crohn’s
Treatment may be medical, surgical or a combination of both. In mild cases, no treatment at all may be an option. Some people may find relief from their symptoms by altering their diet or going on a special liquid diet.
The treatment choice will depend on the type of Crohn’s, and is tailored for each individual.
A range of drugs are used to treat Crohn’s. Initially, the aim is to reduce inflammation to bring relief from the symptoms (induce remission). Once the condition is under control, drugs will usually be used to maintain remission and prevent relapse – this is called maintenance treatment.
Many of the drugs used in Crohn’s are anti-inflammatory drugs. These include steroids, immunosuppressants such as azathioprine, mercaptopurine and biological drugs like infliximab, adalimumab, ustekinumab and vedolizumab.