Ulcerative colitis(Colitis ulcerosa,UC) is a form ofinflammatory bowel disease(IBD) that causes inflammation and ulcers in thecolon. The disease is a type of colitis, which is a group of diseases that cause inflammation of the colon, the largest section of the large intestine, either in segments or completely. The main symptom of active disease isdiarrheamixed with blood.
Ulcerative colitis has much in common with Crohn’s disease, another form of IBD, but what sets it apart from Crohn’s disease is that ulcerative colitis, as its name suggests, only affects the colon and rectum, leaving the rest of the gastrointestinal tract unscathed, while Crohn’s disease can affect the whole GI tract from mouth to anus. Also, surgical removal of the colon and rectum cures ulcerative colitis, which actually means the disease does not recur after surgery, unlike Crohn’s disease, which has a tendency to recur after surgery to remove the abnormal part of the bowel and connect the healthy ends. Ulcerative colitis is an intermittent disease, with periods of exacerbated symptoms, and periods that are relatively symptom-free. Although the symptoms of ulcerative colitis can sometimes diminish on their own, the disease usually requires treatment to go intoremission. Ulcerative colitis has anincidenceof 1 to 20 cases per 100,000 individuals per year, and aprevalenceof 8 to 246 per 100,000 individuals.
The disease is more prevalent in northern countries of the world, as well as in northern areas of individual countries or other regions. Rates tend to be higher in more affluent countries, which may indicate the increased prevalence is due to increased rates of diagnosis. It may also indicate that an industrial or Western diet and lifestyle increases the prevalence of this disease, including symptoms which may or may not be related to ulcerative colitis. Although UC has no known cause, there is a presumedgeneticcomponent to susceptibility. The disease may be triggered in a susceptible person by environmental factors. Dietary modification may reduce the discomfort of a person with the disease.
Like Crohn’s disease, ulcerative colitis is both classed as and managed as anautoimmune disease.Managementis with anti-inflammatory drugs,immunosuppression, andbiological therapytargeting specific components of the immune response.Colectomy(partial or total removal of the large bowel through surgery) is occasionally necessary if the disease is severe, does not respond to treatment, or if significant complications develop. A totalproctocolectomy(removal of the entirety of the large bowel and rectum) cancureulcerative colitis as the disease only affects the large bowel and rectum and does not recur after removal of the latter. While extra-intestinal symptoms will remain, complications may develop.
What causes Ulcerative Colitis?
There are no direct known causes for ulcerative colitis, but there are many possible factors such as genetics and stress.
Genetic factors – A genetic component to the etiology of ulcerative colitis can be hypothesized based on the following:
Aggregation of ulcerative colitis in families.
Identical twin concordance rate of 10% and dizygotic twin concordance rate of 3%
Ethnic differences in incidence
Genetic markers and linkages
There are 12 regions of the genome that may be linked to ulcerative colitis, including, in the order of their discovery, chromosomes 16, 12, 6, 14, 5, 19, 1, and 3, but none of these loci have been consistently shown to be at fault, suggesting that the disorder arises from the combination of multiple genes. For example, chromosome band 1p36 is one such region thought to be linked to inflammatory bowel disease.
Some of the putative regions encode transporter proteins such as OCTN1 and OCTN2. Other potential regions involve cell scaffolding proteins such as the MAGUK family. There may even be human leukocyte antigen associations at work. In fact, this linkage on chromosome 6 may be the most convincing and consistent of the genetic candidates.
Multiple autoimmune disorders have been recorded with the neurovisceral and cutaneous genetic porphyrias including ulcerative colitis, Crohn’s disease, celiac disease, dermatitis herpetiformis, diabetes, systemic and discoid lupus, rheumatoid arthritis, ankylosing spondylitis, scleroderma, Sjogren’s disease and scleritis. Physicians should be on high alert for porphyrias in families with autoimmune disorders and care must be taken with potential porphyrinogenic drugs, including sulfasalazine.
Diagnosis of Ulcerative Colitis
The initial diagnostic workup for ulcerative colitis includes the following:
A complete blood count is done to check for anemia; thrombocytosis, a high platelet count, is occasionally seen
Electrolyte studies and renal function tests are done, as chronic diarrhea may be associated with hypokalemia, hypomagnesemia and pre-renal failure.
Liver function tests are performed to screen for bile duct involvement: primary sclerosing cholangitis.
Stool culture, to rule out parasites and infectious causes.
Erythrocyte sedimentation rate can be measured, with an elevated sedimentation rate indicating that an inflammatory process is present.
C-reactive protein can be measured, with an elevated level being another indication of inflammation.
sigmoidoscopy a type of endoscopy can detect presence of ulcers in the large intestine after a trial of enema.
Although ulcerative colitis is a disease of unknown causation, inquiry should be made as to unusual factors believed to trigger the disease. Factors may include: recent cessation of tobacco smoking; recent administration of large doses of iron or vitamin B6; hydrogen peroxide in enemas or other procedures.
About 21% of inflammatory bowel disease patients use alternative treatments. A variety of dietary treatments show promise, but they require further research before they can be recommended.