Ulcerative colitis (Colitisulcerosa, UC) is a form of inflammatory bowel disease (IBD).Ulcerative colitis is a form of colitis, a disease of the intestine,specifically the large intestine or colon,that includes characteristic ulcers, or open sores, in the colon. The main symptomof active disease is usually constant diarrhea mixedwith blood, of gradual onset. Because of the name, IBD is often confused with irritable bowel syndrome("IBS"), a troublesome, but much less serious, condition. Ulcerativecolitis has similarities to Crohn'sdisease, another form of IBD. Ulcerative colitis is an intermittentdisease, with periods of exacerbated symptoms, and periods that are relativelysymptom-free. Although the symptoms of ulcerative colitis can sometimesdiminish on their own, the disease usually requires treatment to go into remission.
Ulcerative colitis occurs in 35–100 people for every 100,000 in the UnitedStates, or less than 0.1% of the population. The disease is more prevalent innorthern countries of the world, as well as in northern areas of individualcountries or other regions. Although ulcerative colitis has no known cause,there is a presumed genetic component to susceptibility. The disease may betriggered in a susceptible person by environmental factors. Although dietarymodification may reduce the discomfort of a person with the disease, ulcerativecolitis is not thought to be caused by dietary factors. Although ulcerativecolitis is treated as though it were an autoimmunedisease, there is no consensus that it is such. Treatment is withanti-inflammatory drugs, immunosuppression,and biological therapytargeting specific components of the immune response. Colectomy(partial or total removal of the large bowel through surgery) is occasionallynecessary, and is considered to be a cure for the disease.
The clinical presentation of ulcerative colitis depends on theextent of the disease process. Patients usually present with diarrhea mixedwith blood and mucus,of gradual onset. They also may have signs of weight loss, and blood on rectalexamination. The disease is usually accompanied with different degrees ofabdominal pain, from mild discomfort to severely painful cramps.
Ulcerative colitis is associated with a general inflammatory process thataffects many parts of the body. Sometimes these associated extra-intestinalsymptoms are the initial signs of the disease, such as painful, arthritic kneesin a teenager. The presence of the disease cannot be confirmed, however, untilthe onset of intestinal manifestations.
Extent of involvement
Diagram of the Human Intestine
Ulcerative colitis is normally continuous from the rectum up the colon.The disease is classified by the extent of involvement, depending on how far upthe colon the disease extends:
- Distal colitis, potentially treatable with enemas
- Proctitis: Involvement limited to the rectum.
- Proctosigmoiditis: Involvement of the rectosigmoid colon, the portion of the colon adjacent to the rectum.
- Left-sided colitis: Involvement of the descending colon, which runs along the patient's left side, up to the splenic flexure and the beginning of the transverse colon.
- Extensive colitis, inflammation extending beyond the reach of enemas:
- Pancolitis: Involvement of the entire colon, extending from the rectum to the cecum, beyond which the small intestine begins.
Severity of disease
Colonic pseudopolyps of a patient with intractable ulcerativecolitis. Colectomyspecimen.
In addition to the extent of involvement, UC patients may also becharacterized by the severity of their disease.
- Mild disease correlates with fewer than four stools daily, with or without blood, no systemic signs of toxicity, and a normal erythrocyte sedimentation rate (ESR). There may be mild abdominal pain or cramping. Patients may believe they are constipated when in fact they are experiencing tenesmus, which is a constant feeling of the need to empty the bowel accompanied by involuntary straining efforts, pain, and cramping with little or no fecal output. Rectal pain is uncommon.
- Moderate disease correlates with more than four stools daily, but with minimal signs of toxicity. Patients may display anemia (not requiring transfusions), moderate abdominal pain, and low grade fever, 38 to 39 �C (100 to 102 �F).
- Severe disease, correlates with more than six bloody stools a day, and evidence of toxicity as demonstrated by fever, tachycardia, anemia or an elevated ESR.
- Fulminant disease correlates with more than ten bowel movements daily, continuous bleeding, toxicity, abdominal tenderness and distension, blood transfusion requirement and colonic dilation (expansion). Patients in this category may have inflammation extending beyond just the mucosal layer, causing impaired colonic motility and leading to toxic megacolon. If the serous membrane is involved, colonic perforation may ensue. Unless treated, fulminant disease will soon lead to death.
Patients with ulcerative colitis can occasionallyhave aphthousulcers involving the tongue, lips,palate and pharynx
Pyoderma gangrenosum on the leg of a patient with Crohn'sdisease.
As ulcerative colitis is believed to have a systemic (i.e.,autoimmune) origin, patients may present with comorbiditiesleading to symptomsand complications outside the colon. Theseinclude the following: