Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that affects the large intestine.
The large intestine consists of the cecum, ascending/tranverse/descending/sigmoid colon and rectum. UC usually begins in the rectum and may continue up into the colon. When inflamed, the intestinal lining can become red, swollen, develop ulcers and bleed. This inflammation and irritation can prevent the large intestine from absorbing enough fluid and salt from stool, leading to diarrhea.
UC is a chronic, lifelong disease with alternating periods of activity and remission. Patients may experience intense symptoms followed by varying periods of time when the symptoms seem to disappear.
The cause of UC is unknown, but it appears to involve dysfunction of the immune system. Protective cells normally present in the gastrointestinal lining are triggered to attack when bacteria and viruses pass through the digestive tract. In patients with UC, this attack continues, even when harmful substances are no longer present – leading to chronic inflammation and irritation. It is not clear whether this immune dysfunction is a cause or result of UC.
UC appears most often in people between the ages of 15 and 35, but may also occur in older or younger populations. About 500,000 Americans have UC, according to the Crohn’s & Colitis Foundation of America (CCFA). Another 500,000 have Crohn’s disease (CD)
, the other major type of IBD.
UC differs from CD in a number of ways. In patients with UC, only the large intestine is affected whereas CD may occur anywhere throughout the digestive tract, including the small and large intestines. Inflammation caused by UC is usually continuous, without any normal tissue appearing between inflamed areas. In CD, there may be patches of normal tissue between inflamed areas. In addition, UC affects only the inner lining of the intestine, so ulcers are not likely to break through the innermost intestinal wall layer (mucosa), as may occur in patients with CD.
Inflammatory bowel diseases such as UC and CD are sometimes confused with irritable bowel syndrome (IBS). However, IBS does not involve inflammation of the intestines, which is present in both UC and CD. Also, IBS does not include bloody diarrhea as a symptom and IBS tests reveal no abnormalities. IBS is not associated with either UC or CD.
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:
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.
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.
Ulcerative colitis (UC) causes inflammation and ulceration in the innermost lining of the large intestine. The large intestine is made up of the cecum, ascending/transverse/descending/sigmoid colon and rectum. In most cases of UC, inflammation begins in the rectum and extends upward into the colon.
UC can be classified into various types, depending on how much of the large intestine is involved. Types of UC include:
- Ulcerative proctitis. Inflammation occurs in the rectum. Ulcerative proctitis is a common and typically mild form of UC. However, it may be a precursor to more serious forms of UC. Approximately 30 percent of all patients with UC were first diagnosed with ulcerative proctitis, according to the Crohn’s & Colitis Foundation of America (CCFA).
- Proctosigmoiditis. Inflammation of the rectum and lower portion of the colon (sigmoid colon). When symptoms are active, patients with this type of UC may experience moderate pain in the lower left-hand area of the abdomen.
- Left-sided colitis (sometimes referred to as limited or distal colitis). Occurs along the left side of the large intestine, from the rectum into the splenic flexure (a bend in the colon, where the transverse and descending colons meet). Symptoms include diarrhea, bloody stool, loss of appetite, weight loss and severe pain on the left side of the abdomen.
- Pancolitis. Affects the entire colon and rectum. Symptoms include diarrhea, severe abdominal pain, cramping, weight loss and night sweats. Serious complications, such as intestinal perforation and massive bleeding, can result from pancolitis, requiring surgery.
- Fulminant colitis. A rare but life-threatening condition that affects the entire colon and rectum, causing severe pain and diarrhea. Patients with this type of UC are at risk of developing toxic megacolon, when the large intestine widens and loses muscle tone. Abdominal distention and rupture may occur, requiring immediate medical attention.
The cause of ulcerative colitis (UC) is unknown. It is believed to involve an overactive immune system that, once triggered to attack bacteria or viruses within the digestive tract, is unable to turn itself off. This continual attack within the large intestine leads to inflammation and irritation of the intestinal walls.
The disease seems to occur equally as often in men as it does in women. Although it is unclear why, when UC occurs among older populations (e.g., people in their 50s and 60s), it tends to be diagnosed more often in men than in women.
Certain factors appear to increase the risk of developing UC. These include:
- Heredity. UC appears to run in families. Approximately 20 percent of patients with UC have a blood relative with some form of inflammatory bowel disease (IBD), according to the Crohn’s & Colitis Foundation of America (CCFA).
- Age. Young people, especially those between the ages of 15 and 35, are more likely to develop UC, although UC may also occur in older or younger populations.
- Race and ethnicity. Whites have a higher risk of developing UC than non-whites. The risk of the disease is greater for people with a Jewish ethnic background (especially those of European descent) than other ethnic groups.
- Environment. UC appears to be a disease of the developed world, occurring primarily in the United States and Europe. It is unclear whether lifestyle (e.g., diet) or possible toxic exposure (e.g., pollutants) in these areas of the world may be related to UC. The risk of UC appears to increase for those living in urban areas and in northern climates.
- Cigarette smoking. Nonsmokers are more likely to develop UC than smokers. For Crohn’s disease (CD) (the other major type of IBD), it is just the opposite – smokers are more likely to develop or experience aggressive forms of CD. However, it is not recommended that patients smoke in order to lessen their risk of UC. It is unclear why smoking appears to decrease the risk of UC.
Factors that may trigger or aggravate UC symptoms include:
- Medications (e.g., antibiotics)
- Hormonal changes
- Lifestyle changes
No clear link has been found between antibiotic use and the development of UC. However, use of antibiotics may upset the natural balance of bacteria in the digestive tract, which can irritate and inflame the intestines and may lead to pseudomembranous colitis (severe inflammation of the large intestine due to the use of antibiotics).
The most common signs and symptoms of ulcerative colitis (UC) include:
- Diarrhea. Loose, watery stool. Inflammation causes the large intestine to empty frequently, resulting in diarrhea. The farther up the large intestine the inflammation occurs, the more loose and watery the stool and the more frequent the bowel movements. Dehydration may occur if too much water and salt exits the body with diarrhea. Because loose, watery stool is more difficult to retain in the rectum, fecal incontinence may also occur.
- Blood or mucus in the stool (including bloody diarrhea). Sores (ulcers) in the lining of the large intestine can bleed and produce pus, resulting in the presence of blood or mucus in stool. Anemia may result if too much blood is lost with stool, which may cause fatigue.
- Abdominal pain. Pain felt in the abdomen may be the result of inflamed tissue lining in the large intestine.
Other signs and symptoms may include:
- Cramping. Muscle contractions that normally occur to move stool through the large intestine may intensify in patients with UC and cause cramping.
- Urgency to have a bowel movement. Patients with UC may experience sudden and urgent sensations to defecate. When patients are unable to make it to a restroom quickly enough to expel stool, fecal incontinence may occur.
- Tenesmus. The inability to pass stool, despite an urge to do so. This may occur in patients with UC where inflammation is confined to the rectum, the last part of the large intestine, just before the anus.
- Unexplained weight loss. This may occur as a result of the loss of body fluids due to diarrhea and loss of nutrients due to malabsorption. Patients with UC experience malabsorption less often than patients with Crohn’s disease (the other major type of inflammatory bowel disease [IBD]) since UC does not affect the small intestine, where most nutrient absorption occurs.
- Fever. Patients with moderate or severe UC may experience a rise in body temperature.
- Nausea and vomiting. Chronic inflammation and irritation of the large intestine due to UC may cause a loss of appetite, feelings of queasiness and vomiting.
Symptoms of UC may range from mild to severe, with half of all patients experiencing mild symptoms. Symptom severity is usually stable – only rarely do patients with mild symptoms later develop more severe signs and symptoms. Examples include:
- Intermittent rectal bleeding
- Mild diarrhea (less than four stools/day)
- Mild abdominal pain
- Mucus discharge
- Painful straining during bowel movements
- Frequent loose, bloody stool (up to 10 stools/day)
- Mild to moderate abdominal pain
- Mild anemia
- Low-grade fever
- Frequent loose stools (more than 10 stools/day)
- Severe abdominal cramping
- Rapid weight loss (unexplained)
Anyone who experiences a persistent change in bowel movements, fever that lasts more than a couple of days, or abdominal pain and bloody stool should seek medical attention immediately.
In pregnant patients, symptoms of UC may increase the risk of fetal death or early labor. Patients with UC who plan on becoming pregnant should consult with their physician about these risks.
The first step in diagnosing ulcerative colitis (UC) is a visit to a physician for a medical history and physical examination. Patients may be asked about the extent and duration of their symptoms, any family history of inflammatory bowel disease (IBD), as well as their eating, drinking or smoking habits.
Blood tests and stool samples may also be required. Blood tests can identify low red blood cell counts (anemia) and high white blood cell counts (which may indicate inflammation or infection). A stool sample analysis (fecal test) can identify bleeding or infection of the large intestine.
Various diagnostic tests may be used to determine if a patient has UC. They may also be used to rule out evidence of infections or other diseases (such as Crohn’s disease, irritable bowel syndrome [IBS], colorectal cancer or diverticulitis) that may be causing the symptoms. These tests include:
Examination of the entire large intestine using a small, flexible tube (with a light and camera) inserted through the anus. This procedure allows physicians to identify the severity and extent of disease. Patients take a laxative prior to the procedure to cleanse the large intestine and are sedated during the procedure.
During colonoscopy, a tissue sample (biopsy) may be taken for evaluation under a microscope. This may help identify the type of IBD that is present. For example, if granulomas (clusters of inflamed cells) are found, a patient may be diagnosed with Crohn’s disease (CD), since these cells do not occur with UC.
Similar to a colonoscopy, but used to examine the lower portion of the large intestine (the sigmoid colon and rectum).
X-rays of the gastrointestinal (GI) tract, after patients receive a dose of a contrast dye (barium) that allows organs to show up clearly on x-rays. Barium may be introduced to the body orally (upper GI barium tests) or via an enema (lower GI barium tests). X-rays can help identify what type of IBD is present (UC will only occur in the large intestine, whereas CD may affect any part of the digestive tract).
Barium x-rays are not considered as reliable as a colonoscopy or sigmoidoscopy for diagnosing UC because the x-rays may miss polyps and do not allow tissue samples to be taken for analysis under a microscope. They are not used in case of moderate to severe UC because of the risk of complications.
Ulcerative colitis (UC) is a lifelong condition. Once it appears, patients may experience symptoms of varying intensity for the rest of their lives, usually in alternating periods of activity and remission.
UC treatment attempts to reduce or eliminate the inflammation caused by the disease, as well as its symptoms (e.g., diarrhea, abdominal pain). Long-term treatment with medication is often recommended. Surgery may be required when medication is ineffective, complications of the condition arise or to treat cancerous or precancerous changes in the large intestine. Less than half of all patients with UC will require surgery at some point during the course of the condition. Removal of the large intestine is the only cure for UC.
Medication is usually the first line of treatment for patients with UC. Patients planning to become pregnant should consult their physician since some of the drugs used to treat UC may cause birth defects. In addition, patients and their physicians will want to weigh the risks and benefits of the different types of drugs. Not all medications will work for all patients.
Medications used to reduce the inflammation caused by UC include:
Reduce inflammation in the lining of the digestive tract. The active component of these drugs is a compound called 5-aminosalicylic acid (5-ASA) – the most common treatment choice for inflammatory bowel disease (IBD). Aminosalicylates can be taken orally or rectally (in enema or suppository form). Side effects may include nausea, vomiting, heartburn, diarrhea and headaches. This type of drug is used for patients with mild to moderate UC.
Used to control inflammation when 5-ASA drugs are not effective. Corticosteroids can be taken orally, rectally or intravenously. Long-term use of corticosteroids can increase a patient’s risk of serious side effects, including high blood pressure, osteoporosis and diabetes. Fluid retention and a rounded/swollen appearance of the face may also occur. The risk of side effects varies depending on the type of corticosteroid used. Corticosteroids are used for patients with moderate to severe UC.
Suppress the body’s ability to create the disease-fighting substances (antibodies) that are attacking the normal tissue lining in patients with UC, causing inflammation. This decreases immune system activity in patients with UC. Usually taken orally, these drugs may not have an impact for weeks or months. Possible side-effects include nausea, vomiting, diarrhea and an increased risk of infections. These medications are used to treat active, severe cases of UC.
Various medications can also be used to treat the symptoms or complications of UC.
- Antidiarrheals. Used to relieve chronic diarrhea that is one of the most common symptoms of UC.
- Laxatives. Used in cases where intestinal swelling causes narrowed passageways and leads to constipation.
- Acetaminophen. Used to relieve pain. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen should not be used by patients with UC as they may intensify symptoms.
- Iron supplements. Used to restore iron loss and treat anemia, which can result from chronic intestinal bleeding.
Blood transfusions may be necessary when there is severe blood loss due to inflammation and ulceration of the intestinal lining.
When medications do not adequately treat the symptoms or complications of UC, surgery may be required. A proctocolectomy (removal of the entire colon and rectum) will cure the condition, as well as remove any risk of colon cancer.
Between 25 and 40 percent of patients with UC will require surgery, according to the National Institutes of Health (NIH). Surgery may be required in cases of massive bleeding, severe illness, colon rupture or to treat cancerous or precancerous changes in the large intestine.
Surgery to remove most of the large intestine will change the way waste is eliminated from the body. During normal digestion, waste moves from the bottom of the small intestine (ileum) into the large intestine. Fluid and salt are absorbed from stool during its transit through the large intestine’s cecum, colon and rectum. The remaining waste is expelled from the body through the anus.
During surgery to remove the colon and rectum, the ileum may be reconstructed and/or reconnected to the abdomen or anal area. This allows waste to be expelled from the body in three different ways. Patients undergoing a proctocolectomy will also need at least one of the following procedures performed:
- Ileostomy. When the ileum is connected to an opening in the abdominal wall (stoma), which allows waste to drain into an ileostomy bag worn at the waist.
- Continent ileostomy. Involves the creation of an internal pouch at the end of the ileum, where waste may be stored. A stoma is also created during this procedure.
- Ileoanal anastomosis (also known as a “pull-through” operation). When the ileum is reconnected directly to the anal region. A pouch is created at the base of the ileum, allowing waste to be stored there before being expelled normally through the anus. Pouchitis may occur after this procedure.
After a proctocolectomy, stool may be watery and patients may need to expel waste more frequently, since the large intestine is no longer there to absorb water from stool. There is the risk of intestinal obstruction (due to scar tissue buildup) after this surgery, which may require hospitalization or additional corrective surgery. Research also indicates that women who receive a proctocolectomy have an increased risk of infertility.
Hospitalization may be necessary to treat patients with UC when they are malnourished or have experienced severe diarrhea or blood loss. A special diet may be recommended, or intravenous feeding (parenteral nutrition) may be required.
Dietary changes and stress management (including regular exercise) are important considerations for patients with UC. Many of the changes recommended to help reduce or prevent symptom flare-up in patients with UC can lengthen periods of remission, helping to improve the quality of life for patients with UC (see Prevention methods).
There is currently no way to prevent ulcerative colitis (UC) from occurring. Once it occurs, however, there are methods that may help reduce or prevent a flare-up of UC symptoms.
UC patients should avoid non-steroidal anti-inflammatory drugs and antibiotics since the use of these drugs can exacerbate UC.
Although diet and stress do not cause UC, they may trigger symptoms in some patients. Thus, certain dietary changes and stress management may help prevent the symptoms of UC.
A healthy diet for patients with UC generally includes foods that will not aggravate the digestive tract, such as soft, bland foods that are low in fiber. Adequate amounts of proteins, calories and vitamins should be consumed. Because food tolerances can differ significantly from person to person, patients may want to consult a dietician for help creating a personalized food plan.
Dietary and lifestyle changes that may help prevent the symptoms of UC include:
- Experiment with fiber. Foods high in fiber (e.g., bran, beans, fresh fruits, vegetables) are usually an important part of a balanced diet. Since fiber can worsen symptoms of UC, patients should experiment with the levels of fiber in their diet. For example, some patients may be able to tolerate fresh fruits and vegetables when they are steamed, baked or stewed. High-fiber foods that may be especially problematic for patients with UC include those in the cabbage family (e.g., broccoli, cauliflower) and very crunchy foods (e.g., raw apples and carrots).
- Avoid problem foods. Any foods that aggravate or cause a flare-up of symptoms in patients with UC should be avoided. This may include spicy foods, popcorn and chocolate.
- Eat smaller meals. Eating smaller amounts of food throughout the day can aid digestion in patients with UC and help prevent symptoms.
- Avoid caffeine, alcohol and carbonated drinks. Alcohol and beverages that contain caffeine (e.g., soda, coffee, tea) stimulate digestion, causing diarrhea.
- Limit dairy products. Patients with UC may also be lactose intolerant, unable to digest the sugar (lactose) found in most dairy products. If so, avoiding these products can help prevent the symptoms of UC.
- Drink plenty of fluids. Drinking plenty of water throughout the day can help a patient with UC remain hydrated and may lessen the severity of UC symptoms.
- Use supplements. Multivitamins can help maintain a healthy nutritional balance for patients with UC who may suffer from diet restrictions and malabsorption problems. Because even natural herbs may interfere with current medications, it is recommended that patients consult their physician before beginning to use any type of supplement.
Stress may aggravate the symptoms of UC, since it disrupts normal digestion. Stress may speed up or slow down the movement of stool through the digestive tract. It can also further irritate intestinal tissue, leading to a worsening of symptoms in patients with UC. Relieving stress through exercise or meditation (e.g., yoga, tai chi) can help reduce symptoms.
For many patients, coping with the symptoms of ulcerative colitis (UC) can be difficult. Symptoms such as chronic diarrhea can include a loss of control (fecal incontinence), which can be embarrassing and limit outdoor activities. Abdominal pain and cramping may make it awkward to be out in public. Patients may not feel comfortable discussing the matter with others.
Patients and their loved ones can take actions to help them cope with this condition. These actions include:
- Get emotional support. Emotional support may lessen stress levels, helping to prevent UC symptoms. Patients with UC may experience isolation, anxiety and embarrassment as a result of their recurring symptoms. Emotional support can help alleviate these feelings. Sources of emotional support include:
- Family and friends
- Support groups
- Mental health professionals
- Stay informed. Learning about UC symptoms, conditions and outcomes can help reduce fear and emotional stress for patients with UC and their loved ones.
- Be prepared. Patients with UC can be prepared for the sudden onset of symptoms, such as diarrhea or fecal incontinence. This may include knowing where bathrooms are and carrying extra underclothing or toilet paper when traveling.
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions related to ulcerative colitis (UC):
- Am I at risk for UC?
- At what point should I be concerned about my symptoms?
- What kind of tests will you need to take to determine the cause of my symptoms? How should I prepare for these tests?
- Could my symptoms be a sign of some other type of inflammatory bowel disease (IBD)?
- Where exactly is the inflammation in my body? How severe is the damage it may have caused to my digestive tract?
- Is something I am eating or drinking causing my UC or aggravating its symptoms? What about smoking? Or stress?
- What type of treatment do you recommend?
- What medication is most appropriate for me? For how long will I have to take it?
- Are there over-the-counter medications I can also take that would help?
- Are there over-the-counter medications that I need to avoid because they could worsen my symptoms, increase the risk of complications or interact with my prescription medications?
- Will I need surgery? What are the risks and benefits of surgery?
- How will I need to change my lifestyle once diagnosed with UC?
- Are there complementary treatments (e.g., nutritional supplements, acupuncture, meditation) you would recommend that may help prevent the symptoms of UC?
- What symptoms or changes should I immediately be reporting to you?
- If my symptoms subside for a period (remission) do you want to be informed when and if they resume?
- Will I need regular follow-up visits or testing? How often?
- Are my children at higher risk for UC or other inflammatory bowel diseases now that I have been diagnosed? Should they be evaluated for the condition?
Individuals who undergo treatment for their disease can expect to be able to keep it under control by staying on their medications and keeping an eye on their stress levels. If the disease is not well controlled or the individual refuses therapy, the disease will progress. Non-compliance with medical regimens can also lead to dehydration, infection and possible sepsis (overwhelming systemic infection with a high mortality). If the disease is left to progress over a period, it may eventually lead to an enlarged colon (toxic megacolon) or colon cancer.
The different diseases that need to be excluded from consideration are gastroenteritis, infectious diarrhea, amebiasis (infection of the GI tract by amoeba), mesenteric adenitis (inflammation of the mesenteric lymph nodes), appendicitis, mesenteric ischemia (lack of blood supply to the small bowel and/or colon), diverticulitis (infection and inflammation of the colon), HIV, and colitis due to drug ingestion (NSAID induced).
Gastroenterologist and general surgeon.
- You or a family member has symptoms of ulcerative colitis.
- Fever and chills develop.
- Frequency of bowel movements or bleeding increases.
- Abdomen becomes distended.
- Jaundice (yellow eyes and skin and dark urine) develops.
- Vomiting begins or abdominal pain increases.
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- “What Should I Eat?” Crohn's & Colitis Foundation. Accessed June 2, 2020. https://www.crohnscolitisfoundation.org/diet-and-nutrition/what-should-i-eat.