Ulcerative Colitis

Ulcerative Colitis (UC) is one of the two main forms of Inflammatory Bowel Disease. The other main form of IBD is a condition known as Crohn’s Disease.

UC is a condition that causes inflammation and ulceration of the inner lining of the rectum and colon. Inflammation is the body’s reaction to injury or irritation, and can cause redness, swelling and pain. Small ulcers develop on the colon’s lining, and these may bleed and produce pus.

The inflammation usually begins in the rectum and lower colon, but it may affect the entire colon. If UC only affects the rectum, it is called proctitis.

The inflamed colon is less able to absorb liquid and this can lead to a larger volume of watery stools. Also, because the colon cannot hold as much as usual, you may have very frequent bowel movements (six or more a day).

It is estimated that around 1 in every 420 people living in the UK has UC; this amounts to around 146,000 people. The condition can develop at any age, but is most often diagnosed between 15 and 25 years old.

Causes of UC

We don’t really know what causes UC, however researchers believe it is caused by a combination of factors: a person’s genes combined with an abnormal reaction of the immune system to certain bacteria in the intestines which is probably triggered by something in the environment.

Symptoms of UC

UC symptoms may range from mild to severe and will vary from person to person. There may be periods without any symptoms, known as remission, and periods when they do occur, which is known as flare-ups. It is also possible to feel well between flare-ups and have no symptoms at all.

Most common symptoms:

  • Diarrhoea – the main symptom, often with blood or mucous depending on how much of the rectum and colon is inflamed and the severity of the inflammation
  • Cramping – these can be severe and often occur before passing a stool
  • Anaemia – this is more likely to develop if you are losing a lot of blood and not eating well
  • Tiredness – from the illness, anaemia, or disrupted sleep
  • Loss of appetite and a loss of weight
  • Feeling generally unwell and feverish

UC can cause further problems in other parts of the body. These can include mouth ulcers, skin rashes and inflammation (redness or pain) in the eyes, skin or joints. Problems outside the large bowel often occur during a flare-up but can also happen while in remission.

Diagnosis and treatment 

If you develop diarrhoea with bleeding and abdominal pain, your doctor may suspect you have UC, particularly if you are a young adult or have a family history of IBD. You will need tests and physical examinations to confirm a diagnosis. These may include:

  • Blood and stool tests – to determine whether you have inflammation somewhere in your body and whether you are anaemic
  • Endoscopies – a doctor or specialist endoscopist uses an endoscope – a long thin, usually flexible, tube with a camera in its tip – to examine your digestive system
  • MRI and CT scans – other tests that are increasingly used to look at the location and extent of inflammation include MRI (Magnetic Resonance Imaging) and CT (Computerised Tomography) scans

Sometimes it can be difficult to tell UC apart from other inflammatory bowel conditions, especially Crohn’s Colitis (Crohn’s Disease in the colon). If it remains unclear you may be given a diagnosis of IBD Unclassified (IBDU) or Indeterminate Colitis. This should not affect the start of any treatment.

There are treatments that can help to settle flare-ups and prevent complications:


Drug treatment for Ulcerative Colitis usually aims to reduce symptoms and control flare-ups, and then to prevent a relapse once the disease is under control. This can mean that you need to take your medication on an ongoing basis, sometimes for many years. Or, you may need only a short course of drugs.


If medicines don’t improve symptoms, a gastroenterologist may recommend an operation to remove the large bowel. By talking to a specialist, the best and most suitable operation can be explored. Recent estimates suggest that about two in 10 people with UC may eventually need surgery, depending on how severe the disease is and which part(s) of the colon are affected.

Living with UC

Generally, the most important thing is to eat a nutritious and balanced diet to maintain your weight and strength, and to drink sufficient fluids to stop you getting dehydrated.

Certain foods may affect symptoms, for example, when you have a flare-up, you may discover that bland, soft foods cause less discomfort than raw vegetables, spicy or high-fibre foods.

UC is such an ‘individual’ condition and people’s experiences vary so widely. Also, so much can depend on the severity of your condition and on whether your disease is in a quiet or an active phase.

Chrohn’s and Colitis UK offers extensive information and support for those affected by IBD.

Here at The New Malden Diagnostic Centre we have a team of highly experienced gastroenterologists, colorectal and general surgeons who specialise in the diagnosis and treatment of a wide variety of gastrointestinal disease as well as pancreatic disorders.

If you feel you need advice and help managing your condition or you are yet to be diagnosed but feel you have symptoms, please do not hesitate to get in touch, by calling 020 8942 6555 or visiting our website.