Complications of Ulcerative Colitis

If treatment is not carefully followed, and occasionally in very severe cases, complications may occur. These include:


This is bleeding from the bowel and may require blood transfusions or an operation.


This is a hole in the bowel caused by thinning of the lining due to inflammation. It may cause leaking of the contents into the abdomen (peritonitis) and may require an operation.

Stricture formation

Strictures are areas of narrowing in the bowel caused by inflammation and scarring. This leads to obstruction and may require surgical removal.

Abscess formation

Pockets of pus, usually occurring close to the anus, which may require surgical drainage.

Anorectal disease

Such as fissures. These are painful cracks in the lining causing bleeding on defaecation (passage of a bowel motion). Very occasionally they may lead to a fistula.

Dysplasia and carcinoma

Patients with long-standing (over 10 years) extensive colitis may develop a pre-cancerous condition, dysplasia. This leads to  an increased risk of bowel cancer. Dysplasia is a change in the appearance under the microscope of the mucosa, which should alert the doctors to the risk of cancer developing.


May affect any joints, but especially those in the large joints such as the knees & hips. Inflammation in the bottom of the spine is called sacroileitis. Arthritis is usually related to activity in the bowel and therefore controlling this may help resolve pains in the joints. Arthralgia (painful joints without swelling & deformity) is usually unrelated to bowel activity.

Sclerosing cholangitis

Sclerosing cholangitis is an inflammatory disease causing fibrosis (stiffening) of the bile ducts both inside and outside the liver and hampering the flow of bile.  It may eventually lead to jaundice or cirrhosis of the liver. It is a rare disease that may be associated with inflammatory bowel disease, particularly ulcerative colitis (around 1-4%).

How is it caused?

The cause is unknown but certain factors have been suggested to play a part in its development, such as:

  • toxins, derived from bacteria in the gut or environmental increased copper in the liver
  • viral infections
  • genetic susceptibility 

What are the symptoms?

The disease may be present for many years without symptoms, but may eventually show signs of:

  • jaundice
  • pruritis (itchy skin)
  • abdominal pain
  • enlarged liver
  • gastrointestinal bleeding

It is frequently first detected by abnormal blood tests revealing liver damage. 
It tends to occur more commonly in men and after 30-50 years of age and the risk of cancer developing in the bowel is increased significantly in patients with sclerosing cholangitis. Careful follow up of these patients is essential.

What is the treatment?

Treatment is both medical and surgical.


Few drug treatments have been effective in sclerosing cholangitis other than supplements of Vitamin D and Calcium to prevent osteoporosis and reduction of bone cells.

Endoscopic retrograde cholangio pancreatography (ERCP) and balloon dilatation of the bile duct strictures have sometimes been successful in reducing hospital admissions and improving blood results.


This is generally a means of bypassing the strictured ducts, inserting stents (small plastic drainage tubes) to keep the ducts patent or, ultimately, a liver transplant. Sometimes continuing inflammation in the bowel is associated with damage to the liver, leading to distortion of the bile ducts both inside and outside the liver. This initially causes abnormal liver function tests, but if damage progresses it ultimately may cause cirrhosis of the liver. In advanced cases a liver transplant may be necessary.


When an ileo-anal anastomosis has been performed the pouch made from loops of small bowel may become inflamed. This leads to a marked increase in the number of stools passed and sometimes to pain and bleeding. It is believed that pouchitis is due to problems with the bacteria which colonise the pouch after formation. It is therefore treated with courses of antibiotics such as Augmentin or ciprofloxacin. Prednisolone may sometimes be helpful and a very exciting development has been the demonstration that a cocktail of 8 different friendly probiotic bacteria – VSL-#3 – is often effective in preventing pouchitis from recurring. We have found that the LOFFLEX diet is very useful in controlling persistent cases of pouchitis when frequent relapses occur after other treatments. provides general information only and should not be regarded as a substitute for medical advice from your own doctor or healthcare provider.
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