How does ulcerative colitis affect the digestive system

T cells identify foreign substances and defend the body against infection. Certain genetic variations may make some individuals more prone to an overactive immune response to the bacteria and other microbes in the intestines, which may cause the chronic inflammation that occurs in ulcerative colitis.

Another possible explanation is that ulcerative colitis occurs when the immune system malfunctions and attacks the cells of the intestines, causing inflammation. The inheritance pattern of ulcerative colitis is unknown because many genetic and environmental factors are likely to be involved. Even though the inheritance pattern of this condition is unclear, having a family member with ulcerative colitis increases the risk of developing the condition.

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Contact a health care provider if you have questions about your health. Ulcerative colitis. From Genetics Home Reference. Description Ulcerative colitis is a chronic disorder that affects the digestive system. Frequency Ulcerative colitis is most common in North America and Western Europe; however the prevalence is increasing in other regions.

Causes A variety of genetic and environmental factors are likely involved in the development of ulcerative colitis. Inheritance The inheritance pattern of ulcerative colitis is unknown because many genetic and environmental factors are likely to be involved.

Research Studies from ClinicalTrials. Meta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to Nat Genet. Epub Feb 6. Erratum in: Nat Genet. N Engl J Med. Damage to the nerves and muscles of the bowel wall causes ileus a condition in which the normal contractile movements of the intestinal wall temporarily stop , and thus the intestinal contents are not propelled along their way.

Abdominal expansion distention develops. As fulminant colitis worsens, the large intestine loses muscle tone and within days—or even hours—it starts to expand a condition sometimes referred to as toxic megacolon. This complication may cause a high fever and abdominal pain.

Sometimes there is a perforation of the large intestine and the person develops peritonitis Peritonitis Abdominal pain is common and often minor. X-rays of the abdomen may show expansion of the bowel and the presence of gas inside the wall of the paralyzed sections of intestine. Typical symptoms include bleeding during a bowel movement, fatigue, and weakness The risk of colon cancer is highest when the entire large intestine is affected and increases the longer the person has had ulcerative colitis.

However, people who have both inflammatory bowel disease and inflammation of the bile ducts primary sclerosing cholangitis Primary Sclerosing Cholangitis Primary sclerosing cholangitis is inflammation with progressive scarring and narrowing of the bile ducts in and outside the liver. Eventually, the ducts become blocked and then obliterated Colonoscopy Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube endoscope.

Endoscopy can also be used to treat many disorders because doctors are able to pass instruments During colonoscopy, tissue samples are taken from areas throughout the large intestine for examination under a microscope to detect the early warning signs of cancer dysplasia. This removal and examination of tissue is called a biopsy. In a newer type of colonoscopy called chromoendoscopy, dyes are inserted into the colon during colonoscopy to highlight cancerous malignant and precancerous areas and may better help doctors identify areas for biopsy.

Other complications can occur, as in Crohn disease. When ulcerative colitis causes a flare-up of gastrointestinal symptoms, people also may have the following:. Inflammation of the whites of the eyes episcleritis Episcleritis Episcleritis is inflammation of the tissue lying between the sclera the tough, white, fiber layer covering the eye and the conjunctiva the membrane that lines the eyelid and covers the white Inflamed skin nodules erythema nodosum Erythema Nodosum Erythema nodosum is a form of panniculitis inflammation of the fat layer beneath the skin that produces tender red or violet bumps nodules under the skin, most often over the shins but occasionally When ulcerative colitis is not causing a flare-up of gastrointestinal symptoms, people still may have complications that occur entirely without relation to the bowel disease such as the following:.

Dusky purple skin sores that may contain pus pyoderma gangrenosum Pyoderma Gangrenosum Pyoderma gangrenosum is a chronic inflammatory skin disease of unknown cause that results in large sores forming on the skin.

See also Introduction to Hypersensitivity Reactions and Inflammatory Inflammation of the spine ankylosing spondylitis Ankylosing Spondylitis Ankylosing spondylitis is a spondyloarthritis characterized by inflammation of the spine spondylitis , large joints, and fingers and toes, resulting in stiffness and pain.

Prolonged joint pain Inflammation of the inside of the eye uveitis Uveitis Uveitis is inflammation anywhere in the pigmented inside lining of the eye, known as the uvea or uveal tract. The uveal tract may become inflamed because of infection, injury, a bodywide autoimmune Severe liver disease can include inflammation of the liver chronic active hepatitis Overview of Chronic Hepatitis Chronic hepatitis is inflammation of the liver that lasts at least 6 months.

Common causes include hepatitis B and C viruses and certain drugs. Most people have no symptoms, but some have vague The scar Inflammation of the bile ducts may appear many years before any intestinal symptoms of ulcerative colitis. The inflammation greatly increases the risk of cancer of the bile ducts and also seems to be associated with a sharp increase in the risk of colon cancer. Doctors suspect ulcerative colitis in a person with recurring bloody diarrhea accompanied by cramps and a strong urge to defecate, particularly if the person has other complications, such as arthritis or liver problems, and a history of similar attacks.

Doctors examine the stool to look for parasites, rule out bacterial infections, and assess inflammation. Sigmoidoscopy Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube endoscope. This procedure permits a doctor to directly observe the severity of the inflammation, take samples of mucus or stool for culture, and remove tissue samples of affected areas for examination under a microscope called a biopsy.

Even during symptom-free intervals, the intestine rarely appears entirely normal, and tissue samples removed for examination under a microscope usually show chronic inflammation. A colonoscopy is usually not necessary, but doctors may need to do a colonoscopy if the inflammation extends beyond the reach of the sigmoidoscope. Blood tests do not confirm the diagnosis of ulcerative colitis but may reveal that the person has anemia, increased numbers of white blood cells occurs with inflammation , a low level of the protein albumin, and an elevated erythrocyte sedimentation rate ESR or C-reactive protein level, which also indicate active inflammation.

A doctor may also do liver tests. X-rays of the abdomen taken after barium is given by enema called a barium enema X-Ray Studies of the Digestive Tract X-rays often are used to evaluate digestive problems. Standard x-rays plain x-rays do not require any special preparation see Plain X-Rays. These x-rays usually can show a blockage or paralysis Other x-rays of the abdomen may also be taken. Doctors examine people when their typical symptoms return, but they do not always do tests.

If symptoms have been more frequent or longer-lasting than usual, doctors may do sigmoidoscopy or colonoscopy and a blood count. Doctors may do other tests to look for infection or parasites. When symptoms are severe, people are hospitalized. Doctors take x-rays to look for a dilated or perforated intestine. Ulcerative colitis is usually chronic, with repeated flare-ups and remissions periods of no symptoms.

The remaining people have some degree of recurring disease. People who have ulcerative proctitis have the best prognosis.

Severe complications are unlikely. In people who have proctitis that has not spread, surgery is rarely required, cancer rates are not increased, and life expectancy is normal. Most people survive if the diagnosis is made during the early stages and the colon is removed in time.

Ulcerative colitis treatment aims to control the inflammation, reduce symptoms, and replace any lost fluids and nutrients. Usually, if the large intestine is swollen, people should eat a low-fiber diet in particular, avoiding foods such as nuts, corn hulls, raw fruits, and vegetables to reduce injury to the inflamed lining of the large intestine. A diet free of dairy products may decrease symptoms and is worth trying but does not need to be continued if no benefit is noted.

Small doses of loperamide are taken for relatively mild diarrhea. For more intense diarrhea, higher doses of loperamide may be needed. In severe cases, however, a doctor must closely monitor the person taking these antidiarrheal drugs because of the risk of fulminant colitis. Routine health maintenance measures Health maintenance In inflammatory bowel diseases, the intestine bowel becomes inflamed, often causing recurring abdominal pain and diarrhea.

Aminosalicylates are drugs used to treat inflammation caused by inflammatory bowel disease. Drugs such as sulfasalazine , olsalazine , mesalamine , and balsalazide are types of aminosalicylates and are used to reduce the inflammation of ulcerative colitis and to prevent flare-ups of symptoms.

These drugs usually are taken by mouth orally , but mesalamine can also be given as an enema or a suppository rectally. Whether given orally or rectally, these drugs are at best moderately effective for treating mild or moderately active disease, but they are more effective for preventing symptoms from reappearing maintaining remission.

People with moderately severe disease usually take corticosteroids in fairly high doses, which frequently induces a dramatic remission. After corticosteroids control the inflammation of ulcerative colitis, sulfasalazine , olsalazine , or mesalamine , or an immunomodulating drug Immunomodulating drugs Ulcerative colitis is a chronic inflammatory bowel disease in which the large intestine colon becomes inflamed and ulcerated pitted or eroded , leading to flare-ups bouts or attacks of Gradually, the prednisone dosage is decreased, and ultimately the prednisone is discontinued.

Budesonide is another corticosteroid that may be used. It has fewer side effects than prednisone but does not work as quickly and is typically given to people whose disease is less severe.

In some cases, doctors may recommend surgery to treat ulcerative colitis or complications. Ulcerative colitis symptoms may cause some people to lose their appetite and eat less, and they may not get enough nutrients. If you have ulcerative colitis, you should eat a healthy, well-balanced diet. The digestive system is made up of the gastrointestinal GI tract—also called the digestive tract—and the liver, pancreas, and the gallbladder.