Patients may experience medical complications as a result of ulcerative colitis (UC). There are two main digestive system related complications that may result from UC:

• Stricture. A narrowing of the colon or rectum. This occurs as the result of scar tissue buildup or swelling due to the chronic inflammation of UC. This may block digestion and require surgery to remove the diseased portion of the bowel. Stricture occurs in a small percentage of patients with UC.
  
  
• Toxic megacolon. Occurs when the large intestine widens, losing muscle tone. This inflammation may cause perforation or rupture of the colon. Symptoms include abdominal distention, fever, pain and shock. This life-threatening condition requires immediate medical attention. Although rare, toxic megacolon is more common among patients with UC than those with Crohn’s disease, the other major type of inflammatory bowel disease (IBD).

UC may also trigger problems outside the intestines, although the reason for this is often unclear. These problems include:

• Liver and biliary system problems. Most patients with UC experience minor changes in their liver functioning. Up to 3 percent of patients with UC have symptoms of mild to severe liver disease, such as inflammation of the liver (hepatitis), scarring of liver tissue (cirrhosis), or inflammation of the bile ducts (primary sclerosing cholangitis).
  
  
• Inflammation of the skin, joints, eyes and lungs. This may include skin rashes (e.g., erythema nodosum), mouth ulcers, eye inflammation and arthritis. These types of inflammation usually only appear when UC symptoms are active. Occasionally, inflammation may occur when UC symptoms are in remission. For example, ankylosing spondylitis (arthritis of the spine that causes back stiffness) may occur in patients with UC during periods of symptom remission.
  
  
• Impaired development in children. Children 18 and under who have UC may experience stunted or delayed physical growth as well as delayed sexual development. The use of steroids to treat UC in children may also retard growth. Aggressive nutritional therapy with supplements (e.g., enteral and parenteral nutrition) can help normalize growth in children with UC.
  
  
• Osteoporosis. A decrease in bone mass that causes bones to be weak and easily fractured. Thirty to 60 percent of patients with IBD have low bone density, according to the Crohn’s & Colitis Foundation of America. The use of steroids increases a person’s risk of osteoporosis. Patients with UC for a long time also have an increased risk of developing osteoporosis. Blood tests can identify vitamin deficiencies that may indicate osteoporosis and periodic bone density testing can identify early osteoporosis in patients with UC. Nutritional supplements and weight-bearing exercises can help build bone strength. There are also drugs that may lessen bone loss associated with IBD and steroid use.
  
  
• Problems during pregnancy. When UC symptoms appear during pregnancy, they can be life-threatening to the fetus and may cause early labor.

Inflammation and ulcers within the large intestine can lead to severe bleeding in the intestinal lining. If too much blood is lost, anemia may result. Blood transfusion may be required in severe cases.

UC may increase a patient’s risk of developing colon cancer. Approximately 5 percent of patients with UC develop colon cancer, according to the National Institutes of Health (NIH). The risk increases when the entire colon is involved and for patients who have had UC for a long period of time.

Research also indicates that patients with colon cancer and UC have a lower survival rate than colon cancer patients without UC.

Periodic colonoscopy and biopsy can help identify the early signs of cancer. These procedures are recommended for patients with IBD throughout the entire large intestine for at least 8 years or with left-sided colitis for at least 12 to 15 years.