Ulcerative colitis (Colitis ulcerosa, 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 symptom of active disease is usually diarrhea mixed with blood, of gradual onset. Ulcerative colitis is, however, a systemic disease that affects many parts of the body outside the intestine.
Because of the name, IBD is often confused with irritable bowel syndrome ("IBS"), a troublesome, but much less serious condition. Ulcerative colitis is similar to Crohn's disease, another form of IBD.
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 into remission.
Ulcerative colitis is a rare disease, with an incidence of about one person per 10,000 in North America. The disease tends to be more common in northern areas.
Although ulcerative colitis has no known cause, there is a presumed genetic component to susceptibility. The disease may be triggered in a susceptible person by environmental factors. Although dietary modification may reduce the discomfort of a person with the disease, ulcerative colitis is not thought to be caused by dietary factors. Although ulcerative colitis is treated as though it were an autoimmune disease, there is no consensus that it is such.
Treatment is with anti-inflammatory drugs and immunosuppression (suppressing the immune system). Colectomy (partial or total removal of the large bowel through surgery) is occasionally necessary, and is considered to be a cure for the disease.
Ulcerative colitis is a systemic disease that affects many parts of the body. Sometimes the extra-intestinal manifestations of the disease are the initial signs, such as painful, arthritic knees in a teenager. It is, however, unlikely that the disease will be correctly diagnosed until the onset of the intestinal manifestations.
Although ulcerative colitis is a disease of unknown causation, inquiry should be made as to unusual factors believed to trigger the disease.Ulcerative Colitis Practice Guidelines in Adults, Am. Coll. Gastroenterology, 2004 (PDF)* 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.
Ulcerative colitis is usually continuous from the rectum, with the rectum almost universally being involved. There is rarely peri-anal disease, but cases have been reported. The degree of involvement endoscopically ranges from proctitis or inflammation of the rectum, to left sided colitis, to pancolitis, which is inflammation involving the ascending colon.
Biopsies of the mucosa are taken to confirm the diagnosis, and microbiological samples may be taken at the time of endoscopy. The pathology in ulcerative colitis typically involves distortion of crypt architecture, inflammation of crypts, frank crypt abcesses, and hemorrhage or inflammatory cells in the lamina propria.
Chromosome band 1p36 is linked to inflammatory bowel disease. Cho, et al., Linkage and linkage disequilibrium in chromosome band 1p36..., Human Molecular Genetics, 2000, Vol. 9, p. 1425*
As discussed above, ulcerative colitis is a systemic disease that affects many areas of the body outside the digestive system. Surgical removal of the large intestine often cures the disease, including the manifestations outside the digestive system.Ulcerative Colitis Practice Guidelines in Adults, Am. Coll. Gastroenterology, 2004 (PDF)* This suggests that the cause of the disease is in the colon itself, and not in the immune system or some other part of the body.
At one time it was a practice to give hydrogen peroxide enemas for certain conditions. And, sometimes hydrogen peroxide is accidentally introduced into the colon during procedures. This is known to cause a condition that appears to be identical to ulcerative colitis. Sheenan, et al., "Ulcerative colitis following hydrogen peroxide enema", Lab Invest 1960; 9:150-167 Pumphery, "Hydrogen peroxide proctitis", Am J Surg 1951, 81: 60-62 Meyer et al., "Hydrogen peroxide colitis: a report of three patients", J Clin Gastroenterol 1981, 3: 31-35
The geographic distribution of ulcerative colitis and Crohn's disease is similar worldwide Podolsky, DK. "Inflammatory bowel disease". New England Journal of Medicine 2002 Aug; 347(6):417-424. with highest incidences in the United States, Canada, the United Kingdom, and Scandinavia. Higher incidences are seen in northern locations compared to southern locations in Europe and the United States Shivananda S et al., Incidence of inflammatory bowel disease across Europe: is there a difference between north and south? Results of the European Collaborative Study on Inflammatory Bowel Disease (EC-IBD). Gut 1996 Nov;39(5):690-7. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9014768&query_hl=13&itool=pubmed_docsum
As with Crohn's disease, ulcerative colitis is thought to occur more commonly among Ashkenazi Jewish peoples than non-Jewish people, although immigrant data from the United States does not support this hypothesis.
The anti-inflammatory action in all these drugs is produced by 5-aminosalicylic acid (5-ASA), the active ingredient in Mesalazine. 5-ASA is produced from the other drugs in the intestine. The aminosalicylates used to treat ulcerative colitis include the following:
5-ASA is poorly-absorbed by the intestines, and hence provides topical relief within the intestine. It is therefore a non-systemic drug. 5-ASA is related to the systemic non-steroidal anti-inflammatory drugs (NSAIDs), such as Aspirin and Ibuprofin, which tend to promote intestinal bleeding, and which should therefore be avoided by persons with ulcerative colitis.
The free radical induction theory, discussed above, proposes that 5-ASA is serving not just as an anti-inflammatory, but also as a free radical trap, destroying the hydroxyl and other radicals that may damage colonic epithelial barrier. Radical Induction Theory of Ulcerative Colitis, World J. Gastroenterology, Jay Pravda, April, 2005 (PDF) *
Patients on high dose sulfasalazine require folic supplementation (1 mg/day) (1000 mcg/day) to maintain normal cell division. This may, however, be counter-productive for patients who are also taking methotrexate, which is a folic acid inhibitor. Folic acid might also be counter-productive for patients taking 6-MP and related drugs that inhibit all cell division.
Corticosteroids reduce inflammation by blocking portions of the leukocyte adhesion cascade which results in inflammation.
Side effects of corticosteroids include Cushing's syndrome, which most often exhibits itself as temporary facial puffyness, called "moon face". Cushing's syndrome can, however, involve psychosis, including manic behavior. These drugs have been known to trigger bipolar disorder. In prescribing these drugs it might be well to inquire as to any family history of bipolar disorder.
Corticosteroids should not be confused with anabolic steroids, the controversial performance-building "steroids" that are banned in certain sports.
The following corticosteroids are used as immune system suppressants in treatment of ulcerative colitis:
Mercaptopurine is a cytostatic drug that is an antimetabolite. The mercaptopurine molecule mimics purine, which is necessary for the synthesis of DNA. With mercaptopurine present, cells are not able to make DNA, and cell division is inhibited.
In administering mercaptopurine it is necessary to monitor the levels of mercaptopurine metabolites in the blood to establish the correct dosage for a patient. An initial concern is hepatotoxicity.
Mercaptopurine inhibits the production of white blood cells generally. Because this makes the body more susceptible to infection, patients need to watched for infections. Vaccinations should also be done with caution.
Frequent blood cell counts are also recommended during administration of mercaptopurine. The drug may be toxic to bone marrow, where many blood components are made. If there is an abnormally large drop in white blood cell count, or any blood cell count, administration of the drug should be halted at least temporarily.
Methotrexate is another immunosuppressive drug. It works by inhibiting folic acid, which is necessary for DNA replication and, therefore, cell division.
TNF is a protein that is released by activated white blood cells, triggering more inflammation, an immune system response and more damage to the mucosa of the colon because of the immune activation. Certain drugs inhibit TNF, hence reducing inflammation and immune system involvement. Infliximab was approved by the FDA for treating ulcerative colitis in March 2005. It is ususally given as an intravenous infusions at weeks 0,2 and 6 and then every six seeks thereafter. It is very useful for inducing and maintaining a remission of ulcerative colitis. Some physicians think that infliximab works better when used in combination with immunmodulators such as 6-mercaptopurine or azathioprine, but there is no definitive evidence based medicine to conclude that infliximab must be used with 6-mp or azathioprine.
Standard treatment for active disease includes Mesalazine suppositories and cortisone foam (Cortifoam(R)). Mesalazine 1 g SUPP QHS or Cortifoam QHS/BID is continued until remission, with response seen usually within three weeks.
Maintenance therapy is with Mesalazine 1g QHS or Q3HS. Those with anal irritation or discomfort from the suppositories may switch to oral medications, such as sulfasalazine, Mesalazine, or Colazol, although they are not as effective as suppositories for proctitis. Maintenance therapy is not recommended for those with a first episode that responded to the Mesalazine. Steroid foam is not shown to prevent relapse.
Systemic steroids such as prednisone are not used unless proctitis fails to respond to the above treatments. Kornbluth A, Sachar DB. "Ulcerative colitis practice guidelines in adults (update): American College of Gastroenterology, Practice Parameters Committee". Am J Gastroenterol 2004 Jul; 99(7):1371-85. *
Patients often respond to topical agents alone, such as Mesalazine, or hydrocortisone enemas. Again, the Mesalazine is preferred for maintenance therapy.
Oral anti-inflammatory drugs require four to six weeks to work.
Once remission is induced, maintenance levels can be used: sulfasalazine 2 g/day, mesalamine 1.2-2.4 g/day, or olsalazine 1 g/day. Patients on high dose sulfasalazine require folic supplementation (1 mg/day) because it inhibits folate absorption.
If oral Mesalazine is still not working, prednisone should be given, starting at 40-60 mg/day. Prednisone should take effect within 10-14 days. The dose should then be tapered by about 5 mg/week until it can be stopped altogether.
Refractory ulcerative colitis. Patients with toxic megacolon (colonic dilation > 6 cm and toxic appearing) who do not respond to steroid therapy within 72 hours should be consulted for colectomy. Those with less severe disease but do not respond to IV steroids within 7-10 days should be considered for colectomy or IV cyclosporine. IV cyclosporine at a rate of 2 mg/kg/day and if no response in 7-10 days, colectomy should be considered. If response is seen, oral cyclosporine at 8 mg/kg/day should be continued for 3-4 months while 6-MP or azathioprine is introduced. Those already on 6-MP or azathioprine should continue with these medications. A cholesterol level should be checked in patients taking cyclosporine as low cholesterol may predispose to seizures. Also, prophylaxis against PCP (Pneumocystis carinii) pneumonia is advised.
Ulcerative colitis is a disease that affects many parts of the body outside the intestinal tract. In rare cases the extra-intestinal manifestations of the disease may require removal of the colon. Ulcerative Colitis Practice Guidelines in Adults, Am. Coll. Gastroenterology, 2004 (PDF)*
Vitamin B6 and iron may be associated with increased hydrogen peroxide levels, and should not be taken in excess under this theory. Radical Induction Theory of Ulcerative Colitis, World J. Gastroenterology, Jay Pravda, April, 2005 (PDF) *
Helminthic therapy using the whipworm Trichuris suis has been shown in a randomized control trial from Iowa to show benefit in patients with ulcerative colitis. The therapy tests the hygiene hypothesis which argues that the absence of helminths in the colons of patients in the western world may lead to inflammation. Both helminthic therapy and fecal bacteriotherapy induce a characteristic Th2 white cell response in the diseased areas, which is somewhat paradoxical given that ulcerative colitis immunology was thought to classically involve Th2 overproduction Summers RW et al., Trichuris suis therapy for active ulcerative colitis: a randomized controlled trial. Gastroenterology. 2005 Apr;128(4):825-32. *.
An increased amount of colonic sulfate-reducing bacteria has been observed in some patients with ulcerative colitis, resulting in higher concentrations of the toxic gas hydrogen sulfide. The role of hydrogen sulfide in pathogenesis is unclear. It has been suggested that the protective benefit of smoking that some patients report is due to hydrogen cyanide from cigarette smoke reacting with hydrogen sulfide to produce the nontoxic isothiocyanate. Another unrelated study suggested sulphur contained in red meats and alcohol may lead to an increased risk of relapse for patients in remission *Roediger et al. "Colonic sulfide in pathogenesis and treatment of ulcerative colitis.", Dig Dis Sci. 1997 Aug;42(8):1571-9. PMID 9286219*Levine et al. "Fecal hydrogen sulfide production in ulcerative colitis.", Am J Gastroenterol. 1998 Jan;93(1):83-7. PMID 9448181.
One controversial theory claims that Mycobacterium paratuberculosis which is responsible for Johne's disease in cows, sheep and goats has many similarities to Crohn's and a lesser extent ulcerative colitis. The theory is further that the M. paratuberculosis bacteria are only indirectly responsible, since it is the immune system of the person that overreacts in an allergic fashion to this intestinal bacteria. *
There is much research currently being done to elucidate further genetic markers in ulcerative colitis. Linkage with Human Leukocyte Antigen B-27, associated with other autoimmune diseases, has been proposed.
Autoimmune diseases | Gastroenterology | Inflammations
Colitis ulcerosa | Colitis ulcerosa | Colitis ulcerosa | Rectocolite hémorragique | קוליטיס כיבית | Ulcerozni kolitis | 潰瘍性大腸炎 | Colitis ulcerosa | Ulcerøs kolitt | Wrzodziejące zapalenie jelita grubego | Colite ulcerosa | Ulcerös kolit
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