Inflammatory bowel disease (IBD) is an umbrella term that includes Crohn’s disease and ulcerative colitis, the two most common forms. Less common inflammatory bowel diseases include Behcet’s disease, ischaemic colitis and lymphocytic colitis.
Sometimes in patients who have inflammation in the colon only, it is difficult to tell if they have ulcerative colitis or Crohn’s disease within the colon, in which case the IBD is classified as indeterminate colitis.
Inflammatory bowel disease is different from irritable bowel syndrome (IBS) in that there is a physical cause for the symptoms experienced.
Comparing Crohn’s disease and ulcerative colitis
The two diseases can produce a similar pattern of symptoms but they do have distinct differences in the regions of the bowel that they affect.
Ulcerative colitis impacts only on the colon. It varies between patients; in some it affects the full length of the colon from the anus to the point where the colon meets the small bowel, in others just a small region.
Crohn’s disease can occur anywhere in the digestive tract, from the oesophagus to the anus, but occurs most often in the part of the small intestine furthest from the stomach and in the part of the colon that leads on from there.
All forms of inflammatory bowel disease are autoimmune diseases. The body’s immune response homes in on the tissue in the gut, causing damage and inflammation.
How common is inflammatory bowel disease?
Around 90,000 people in the UK are living with Crohn’s disease while 120,000 more have ulcerative colitis. It’s not very common but it’s not very rare, so most people know someone who at least knows someone else who has been affected, either themselves or in their close family.
Inflammatory bowel disease is more common in white Europeans, especially those of Jewish origin, and less common in people from developing countries, which may be down to different gut bacteria, or may simply be may be due to a reduced level of diagnosis.
Symptoms of inflammatory bowel disease
The symptoms of the two main inflammatory bowel diseases are often similar, and can include:
- Bloody stools or mucus in the stools
- Abdominal pain
- Weight loss
Both Crohn’s disease and ulcerative colitis tend to flare up, so the symptoms follow a cycle of being more and then less intense.
Diagnosing inflammatory bowel disease
Inflammatory bowel disease is diagnosed using several steps:
- Dr Ana Wilson will first discuss your symptoms, how they affect you and your family history. Around 20% of sufferers will have a family member with the disease.
- This is followed by a series of physical examinations and tests. Your stools will be tested, you will have a series of blood tests and Dr Wilson will arrange for a diagnostic colonoscopy. This involves looking inside your body using a camera on a flexible tube that is inserted through the anus into the colon and up towards the small bowel.
- Sometimes Dr Wilson may recommend a capsule endoscopy, in which you swallow a large pill that contains a camera. As this passes through the gut, it takes pictures of the inside wall.
- From the images produced by capsule endoscopy or colonoscopy, Dr Wilson will either rule out inflammatory bowel disease or will give you a definite diagnosis of either ulcerative colitis or Crohn’s disease. Only very rarely would you be diagnosed with one of the other inflammatory bowel diseases.
Treating inflammatory bowel disease
The two main IBD diseases are generally treated in the same way, although there are differences. Read more…
Living with inflammatory bowel disease
Living with inflammatory bowel disease can be very testing due to the frequency and urgency of diarrhoea and the discomfort of abdominal pain during flare-ups. Read more…