Ulcerative Colitis

  • Ulcerative colitis (UC) is an inflammation of the large intestine (colon).
  • The cause of ulcerative colitis is unknown.
  • Intermittent rectal bleeding, crampy abdominal pain, and diarrhea often are symptoms of ulcerative colitis.
  • The diagnosis of ulcerative colitis can be made with a barium enema. Still, direct visualization (sigmoidoscopy or colonoscopy) is the most accurate means of diagnosis.
  • Long-standing ulcerative colitis is a risk factor for colon cancer.
  • Treatment of ulcerative colitis may involve both medications and surgery.
  • Ulcerative colitis can also cause inflammation in joints, spine, skin, eyes, liver, and bile ducts.

Ulcerative Colitis Diet

No clinical or scientific evidence supports the theory that a specialized diet may cause or benefit individuals with ulcerative colitis (UC). However, patients may find that certain foods aggravate ulcerative colitis symptoms, and they should avoid such foods. The most common symptoms of ulcerative colitis are rectal bleeding, abdominal cramping, and diarrhea. Some people recommend avoiding a high fiber diet (such as raw fruits, vegetables, seeds, nuts, etc.) and other foods that aggravate symptoms. It may be reasonable to keep a food journal to track what foods aggravate symptoms and foods that don’t worsen symptoms (for example, bananas, white rice, white bread, applesauce, bland soft foods, etc.) Discuss your dietary needs with your treating doctor or a dietician that specializes in ulcerative colitis and diet.

Ulcerative Colitis

Ulcerative colitis is considered to be related to Crohn’s disease, another chronic inflammatory disease of the intestines (both are referred to as inflammatory bowel disease).

Ulcerative colitis is a chronic inflammation of the large intestine (colon). The colon is the digestive system where water is removed from undigested material, and the remaining waste material is stored. The rectum is the end of the colon adjacent to the anus. In patients with ulcerative colitis, ulcers and inflammation of the colon’s inner lining lead to symptoms of abdominal pain, diarrhea, and rectal bleeding.

Ulcerative colitis is closely related to another condition of inflammation of the intestines called Crohn’s disease. Together, they are frequently referred to as inflammatory bowel disease (IBD). Ulcerative colitis and Crohn’s diseases are chronic conditions. Crohn’s disease can affect any portion of the gastrointestinal tract, including all bowel wall layers. It may not be limited to the GI tract (affecting the liver, skin, eyes, and joints). UC only affects the lining of the colon (large bowel). Men and women are affected equally. The most commonly begin during adolescence and early adulthood, but they also can begin during childhood and later in life.

UC is found worldwide but is most common in the United States, England, and northern Europe. It is especially common in people of Jewish descent. Ulcerative colitis is rarely seen in Eastern Europe, Asia, and South America, and is rare in the black population. For unknown reasons, an increased frequency of this condition has been observed recently in developing nations.

First degree relatives of people with ulcerative colitis have an increased lifetime risk of developing the disease, but the overall risk remains small.

Symptoms of Ulcerative Colitis

Common symptoms of ulcerative colitis include rectal bleeding, abdominal pain, and diarrhea. Still, there is a wide range of symptoms among patients with this disease. Variability of symptoms reflects differences in the extent of disease (the amount of the colon and rectum inflamed) and the intensity of inflammation. Generally, patients with inflammation confined to the rectum and a short segment of the colon adjacent to the rectum have milder symptoms and a better prognosis than patients with more widespread inflammation.

The different types of ulcerative colitis are classified according to the location and the extent of inflammation:

  1. Ulcerative proctitis refers to inflammation that is limited to the rectum. In many patients with ulcerative proctitis, mild intermittent rectal bleeding may be the only symptom. Other patients with more severe rectal inflammation may also experience rectal pain, urgency (sudden feeling of having to defecate and a need to rush to the bathroom for fear of soiling), and tenesmus (ineffective, painful urge to move one’s bowels caused by the inflammation).
  1. Proctosigmoiditis involves inflammation of the rectum and the sigmoid colon (a short segment of the colon contiguous to the rectum). Symptoms of proctosigmoiditis, like that of proctitis, include rectal bleeding, urgency, and tenesmus. Some patients with proctosigmoiditis also develop bloody diarrhea and cramps.
  1. Left-sided colitis involves inflammation that starts at the rectum and extends up the left colon (sigmoid colon and descending colon). Symptoms of left-sided colitis include bloody diarrhea, abdominal cramps, weight loss, and left-sided abdominal pain.
  2. Pancolitis or universal colitis refers to inflammation affecting the entire colon (right colon, left colon, transverse colon, and the rectum). Symptoms of pancolitis include bloody diarrhea, abdominal pain and cramps, weight loss, fatigue, fever, and night sweats. Some patients with pancolitis have low-grade inflammation and mild symptoms that respond readily to medications. Generally, however, patients with pancolitis suffer more severe disease. They are more challenging to treat than those with more limited forms of ulcerative colitis.
  1. Fulminant colitis is a rare but severe form of pancolitis. Patients with fulminant colitis are too ill with dehydration, severe abdominal pain, protracted diarrhea with bleeding, and even shock. They are at risk of developing toxic megacolon (marked dilatation of the colon due to severe inflammation) and colonic rupture (perforation). Patients with fulminant colitis and toxic megacolon are treated in the hospital with potent intravenous medications. Unless they respond to treatment promptly, surgical removal of the diseased colon is necessary to prevent colonic rupture.

While the intensity of colon inflammation in ulcerative colitis waxes and wanes over time, the location and the extent of disease in a patient generally stays constant. Therefore, when a patient with ulcerative proctitis develops a relapse of their condition, the inflammation usually is confined to the rectum. Nevertheless, a small number of patients (less than 10%) with ulcerative proctitis or proctosigmoiditis can later develop more extensive colitis. Thus, patients who initially only have ulcerative proctitis can later develop left-sided colitis or even pancolitis.

Causes of Ulcerative Colitis

The cause of ulcerative colitis is not known. To date, there has been no convincing evidence that it is caused by infection or is contagious.

Ulcerative colitis likely involves abnormal activation of the immune system in the intestines. This system is supposed to defend the body against harmful bacteria, viruses, fungi, and other foreign invaders. Usually, the immune system is activated only when the body is exposed to harmful invaders. However, in patients with ulcerative colitis, the immune system is abnormally and chronically activated in the absence of any known invader. The continued abnormal activation of the immune system causes chronic inflammation and ulceration portions of the large intestine. This susceptibility to abnormal activation of the immune system is genetically inherited. First degree relatives (brothers, sisters, children, and parents) of patients with IBD are more likely to develop these diseases.

There have been multiple studies using genome-wide association scans investigating genetic susceptibility in ulcerative colitis. These studies have found approximately 30 genes that might increase exposure to ulcerative colitis, including immunoglobulin receptor gene FCGR2A, 5p15, 2p16, ORMDL3, ECM1, and regions on chromosomes 1p36, 12q15, 7q22, 22q13, and IL23R. It is still unclear how these genetic associations will be applied to treating the disease at this early point in the research. Yet, they might have future implications for understanding pathogenesis and creating new treatments.

Diagnosing Ulcerative Colitis

The diagnosis of ulcerative colitis is suggested by abdominal pain symptoms, rectal bleeding, and diarrhea. As there is no gold standard for diagnosis, the ultimate diagnosis relies on a combination of symptoms, the appearance of the colonic lining at the time of endoscopy, histologic features of biopsies of the colonic lining, and studies of the stool to exclude the presence of infectious agents that may be causing the inflammation.

  • Stool specimens are collected for analysis to exclude infection and parasites since these conditions can cause colitis that mimics ulcerative colitis.
  • Blood tests may show anemia (a low red blood cell count), and an elevated white blood cell count, and or a high sedimentation rate (commonly referred to as “sed rate”). An elevated white blood cell count and sed rate reflect ongoing inflammation associated with infection or any chronic inflammation, including UC and Crohn’s disease. Anemia, especially in a young male with chronic pain and diarrhea, should raise the clinician’s suspicion for IBD.
  • Other blood tests also may be checked, including kidney function, liver function tests, iron studies, and C-reactive protein (another sign of inflammation).
  • There is some evidence that a stool test for a calprotectin protein could help identify patients who would benefit from a colonoscopy. Calprotectin seems to be a sensitive marker of intestinal inflammation, meaning that it can be elevated before symptoms become severe. The signs of inflammation are unclear. In the right setting, particularly early in IBD, elevated levels can suggest inflammatory bowel disease. However, this test alone cannot distinguish between different conditions causing the inflammation, so it should be used with caution.
  • Confirmation of ulcerative colitis requires a test to visualize the large intestine. Flexible tubes inserted through the rectum (colonoscopy) permit direct visualization of the inside of the colon to establish the diagnosis and determine the colitis’s extent. Small tissue samples (biopsies) can be obtained during the procedure to determine the colitis’s severity.
  • barium enema X-ray also may indicate the diagnosis of ulcerative colitis. A chalky liquid substance is administered into the rectum during a barium enema and injected into the colon. Barium is so dense that X-rays do not pass through it, so the colon’s outline can be seen on X-ray pictures. A barium enema is less accurate and useful than direct visualization (sigmoidoscopy or colonoscopy) in UC’s diagnosis. A colonoscopy is needed to verify the diagnosis if a barium enema is performed and ulcerative colitis is suspected.

Knowledge of the extent and severity of the colitis is essential in choosing among treatment options.

Some newer diagnostic modalities include video capsule endoscopy and CT/MRI enterography. Video capsule endoscopy (VCE) might be useful for detecting small bowel disease in patients with a diagnosis of UC with atypical features and who might be suspected of actually having Crohn’s disease. With VCE, patients swallow a capsule that contains a camera that takes pictures. At the same time, it travels through the intestines and sends the images wirelessly to a recorder. The images are then reviewed. In a study in 2007, VCE confirmed the presence of small bowel disease in about 15% of patients with ulcerative colitis with atypical features or unclassified inflammatory bowel disease, thus changing the diagnosis to Crohn’s disease (which is not limited to the large bowel as in UC). This might be a useful diagnostic modality in this specific patient population.

CT and MRI enterography are imaging techniques that use oral liquid contrast agents consisting of PEG solutions or low concentration of barium to provide adequate distension of the colon and small intestine. These have been reported to be superior to standard imaging techniques in evaluating small bowel pathology in patients with Crohn’s disease. They have also been shown to provide adequate disease severity estimations in ulcerative colitis (with some under- and overestimations).

Complications of Ulcerative Colitis

Blood transfusions, pancolitis, and toxic megacolon

Patients with ulcerative colitis limited to the rectum (proctitis) or colitis limited to the end of the left colon (proctosigmoiditis) usually do quite well. Brief periodic treatments using oral medications or enemas may be sufficient. Serious complications are rare in these patients. In those with more extensive disease, blood loss from the inflamed intestines can lead to anemia. It may require iron supplements or even blood transfusions. Rarely, the colon can acutely dilate to a large size when the inflammation becomes very severe. This condition is called toxic megacolon. Patients with toxic megacolon are too ill with fever, abdominal pain and distention, dehydration, and malnutrition. Unless the patient improves rapidly with medication, surgery usually is necessary to prevent colonic rupture.

A published Scandinavian study of over 500 patients with ulcerative colitis followed up to 10 years after diagnosis. It was found that their mortality rate did not differ from the general population. Also, after ten years, the cumulative need for colectomy was 9.8%. Nearly 50% of the patients were relapse-free in the last five years of the study. Only 20% of the patients with proctitis or left-sided disease progressed to pancolitis.


Colon cancer is a recognized complication of chronic ulcerative colitis. The risk for cancer begins to rise after eight to ten years of colitis. Patients with only ulcerative proctitis probably do not have an increased risk of colon cancer than the general population. Among patients with active pancolitis (involving the entire colon) for ten years or longer, colon cancer risk is increased compared to the general population. In patients with colitis limited to the colon’s left side, the risk of colon cancer is raised but not as high as in patients with chronic pancolitis.

Patients at higher risk of cancer are patients with positive family histories of colon cancer, long durations of colitis, extensive colon involvement, and primary sclerosing cholangitis (PSC), another complication of ulcerative colitis.

Since these cancers have a more favorable outcome when diagnosed and treated at an earlier stage, yearly colon examinations may be recommended after eight years of known extensive disease. During these examinations, samples of tissue (biopsies) can be taken to search for precancerous changes in the colon’s lining cells. When precancerous changes are found, removal of the colon may be necessary to prevent colon cancer.

Other complications of ulcerative colitis

Complications of ulcerative colitis can involve other parts of the body.

  • Ten percent of the patients can develop inflammation of the joints (arthritis).
  • Some patients have low back pain due to arthritis of the sacroiliac joints.
  • Ankylosing spondylitis (AS) is a type of arthritis that affects the vertebral joints of affected individuals. There seems to be an increased incidence of ankylosing spondylitis among patients with inflammatory bowel disease.
  • Rarely, patients may develop painful, red skin nodules (erythema nodosum). Others can have sore, red eyes (uveitis, episcleritis). Because these particular complications can risk permanent vision impairment, eye pain, or redness are symptoms that require a physician’s evaluation.
  • Diseases of the liver and bile ducts also may be associated with ulcerative colitis. For example, in patients with a rare condition called sclerosing cholangitis, repeated infections and inflammation in the bile ducts can lead to recurrent fever, yellowing of the skin (jaundice), cirrhosis, and the need for transplantation of the liver.
  • Finally, patients with ulcerative colitis also might have an increased tendency to form blood clots, mostly inactive disease.

Treatments for Ulcerative Colitis

Both medications and surgery have been used to treat ulcerative colitis. However, surgery is reserved for those with severe inflammation and life-threatening complications. No drug can cure ulcerative colitis. Patients with ulcerative colitis will typically experience periods of relapse (worsening of inflammation) followed by remission (resolution of inflammation) lasting months to years. During relapses, symptoms of abdominal pain, diarrhea, and rectal bleeding worsen. During remissions, these symptoms subside. Remissions usually occur because of treatment with medications or surgery, but occasionally they occur spontaneously, without any treatment.