Excerpts from excellent articles at About.com.
CROHN’S DISEASE
What is Crohn’s disease?
Crohn’s disease (CD) is a chronic disease that can cause inflammation anywhere along the digestive tract from the mouth to the anus. Of all cases of CD, 45% occur in ileum and colon, 35% in just the ileum, and 20% in just the colon. Unlike ulcerative colitis (UC), which only affects the inner layer, CD commonly involves all layers of the intestinal wall. CD and UC are collectively called inflammatory bowel disease (IBD).
What are the symptoms of CD?
Common symptoms of CD include chronic diarrhea fever, abdominal pain, weight loss, and lack of appetite. Frequent diarrhea can lead to dehydration and nutritional deficiencies. Because the colon is inflamed, it is not as efficient at absorbing water and nutrients from food. Fever is a characteristic of the inflammatory process, may be either high or low-grade, and presents especially during periods of active disease. Night sweats are caused by a fever spiking repeatedly during the night.
Extra-intestinal symptoms include eye inflammation, joint pains, skin rashes or lesions, fistulas and fissures. It is unclear why symptoms develop outside the digestive tract, but they often decrease in severity along with flare-ups.
Eye conditions that can occur with CD include conjunctivitis, episcleritis, uveitis, iritis and keratopathy. Most eye conditions will improve when progress is made in treating the underlying CD, but some may require treatment. Conjunctivitis, or “pink eye,” is an inflammation of the tissue covering the eye and inner surface of the eyelid and may be treated with antibiotics. Uveitis is the inflammation of the middle layer of the eye wall and symptoms include light sensitivity, pain, redness, blurred vision and headaches. Uveitis is commonly treated with corticosteroids; if left untreated it could result in glaucoma or detached retina. Inflammation in the white of the eye is called episcleritis: symptoms include pain and reddening, and treatment is with a vasoconstrictor or corticosteroid. Iritis is inflammation in the iris and symptoms include pain, light sensitivity, blurred vision, redness, decreased pupil size, and floaters. Steroids and antibiotics may be used to treat iritis. Keratophaty is an irregularity in the cornea that does not cause pain or loss of vision, and is therefore usually not treated.
Joint pains may be peripheral arthritis, which causes pain, swelling, and stiffness in the joints. The pain can migrate from one joint to the next and may last for several days or even weeks. Peripheral arthritis does not cause permanent damage to joints and will often improve when the CD is successfully treated. Treatment includes resting painful joints and applying moist heat. Other forms of arthritis may also occur with CD.
Erythema nodosum and pyoderma gangrenosum are skin conditions that may occur before or during a CD flare-up and improve with remission. Erythema nodosum are painful red nodules that develop on the arms or lower legs that affects more women than men. Pyoderma gangrenosum may appear as a blister on the legs or arms, usually at the site of a minor trauma such as a cut. The blister may progress into an ulcer that requires treatment with steroids or antibiotics.
A fissure is a tear or ulcer in the lining of the anal canal and symptoms include painful bowel movements, bright red blood in toilet bowel or on paper, anal lump, and swollen skin tag. Acute fissures may be treated with Sitz baths, fiber to create softer stools, stool softeners, topical hydrocortisone, zinc oxide, petroleum jelly and topical anesthetics. A chronic fissure may need more aggressive treatment including surgery.
A fistula is an abnormal tunnel connecting two body cavities or a body cavity to the skin. Approximately 30% of people with Crohn's Disease develop fistulas. Treatments include antibiotics, immunosuppresants, Remicade, liquid nutrition to replace solid food and surgery.
Are there different forms of CD?
Physicians may use different terms to describe CD, depending on what part of the digestive tract is affected.
The most common form of CD is ileocolits, which affects the ileum (lower end of the small intestine) and the colon (large intestine). Symptoms of this type of CD include diarrhea, cramping pain in the lower right or middle abdomen, and substantial weight loss. In some cases the diseased areas in the ileum and the colon may be contiguous, affecting the ileocecal valve that connects the two sections.
Ileitis, also known as fistulizing or perforating CD, affects only the ileum. Diarrhea, cramping pain in the the lower right or middle abdomen, and discomfort a few hours after eating a meal are common symptoms.
This type of CD can lead to nutritional deficiencies in B12, causing tingling in the fingers or toes (peripheral neuropathy), or folate, which may result in anemia. Complications can include fistulas or abscesses in the right lower quadrant.
Gastroduodenal CD affects the stomach and duodenum (first part of the small intestine). Symptoms include loss of appetite, weight loss, nausea, and vomiting. Vomiting may be a sign of obstruction in narrowed portions of the small intestine. This form of CD is sometimes misdiagnosed as an ulcer, with the CD being discovered after ulcer treatments are ineffective in relieving symptoms.
Jejunoileitis is characterized by intermittent areas of inflammation in the jejunum (middle section of the small intestine). Symptoms include crampy pain after meals, diarrhea, and abdominal pain that can vary from mild to intense. Complications of jejunoileitis include fistulas and malnutrition caused by poor absorption of nutrients.
Crohn's colitis (CC), sometimes called granulomatous colitis, affects only the colon and is sometimes confused with UC. However, there are two distinct differences between CC and UC: inflammation in UC is always contiguous, while in CC it is intermittent throughout the colon, and UC always affects the rectum while CC may not. Symptoms include diarrhea, bleeding from the rectum, and abscesses, fistulas, or ulcers around the anus. Peripheral arthritis and skin conditions are found more frequently with CC than the other types of CD.
What causes CD?
Scientists are not certain what causes CD, so it is known as an idiopathic disease, or a disease with unknown cause. However, there are theories about the origins of CD.
CD is an autoimmune disease, or a disease that is triggered by the immune system. The medical community has noticed seasonal flare-ups (in the spring or autumn) in people with IBD. One theory is that this is a IgE-mediated allergic response.
IgE is a type of immunoglobulin isotype, which is a special protein that helps inactivate organisms that may cause disease. The function of IgE is to bind itself to an antigen and inactivate or remove offending foreign substance. However, IgE tends to attach itself to receptors on mast cells which triggers allergy symptoms such as a runny nose. If an antigen binds itself to one of these IgE cells, the mast cells are activated, and release histamine, heparin, cytokines, leukotrines, and other chemicals.
The presense of leukotrines attracts a new type of cell called an eosinophil. These cells fight off the allergic response, but the chemicals that they use to do so are toxic to the body as well as to the invading infection. The connection between eosinophils and IBD is that three of the four toxic compounds that are released by eosinophil cells are found in in the stool of IBD patients.
A controversial theory is that the bacteria M. paratuberculosis can also cause CD in humans. One study conducted on intestinal tissue removed during surgery from patients with CD, UC or without IBD found that 65% of the CD patient samples contained the bacteria, contrasting with only 12.5% of non-IBD patients. The researchers conclude that the bacteria may play a role in some cases of Crohn's disease.
http://ibdcrohns.about.com/cs/faqsuc/a/ucfaq.htm
ULCERATIVE COLITIS
What is ulcerative colitis?
UC is a chronic disease that causes inflammation in the rectum, colon (large intestine), and infrequently the last part of the small intestine (ileum). The inflammation affects the inner lining of the colon, causing small sores, or ulcers. UC, along with a similar condition known as Crohn's disease, are collectively called Inflammatory Bowel Disease.
UC is a chronic disease that causes inflammation in the rectum, colon (large intestine), and infrequently the last part of the small intestine (ileum). The inflammation affects the inner lining of the colon, causing small sores, or ulcers. UC, along with a similar condition known as Crohn's disease, are collectively called Inflammatory Bowel Disease.
What are the symptoms of UC?
Common symptoms of UC include bloody diarrhea, fever and abdominal pain. There can also be symptoms outside the digestive system which are known as extra-intestinal symptoms.
Diarrhea is a common symptom of UC. Because the colon is inflamed, it is not as efficient at absorbing water and nutrients from food. Frequent diarrhea can lead to dehydration and nutritional deficiencies.
When the lining of the colon becomes inflamed and ulcerated, it bleeds, causing blood to be passed in the stool.
Blood from UC is often thick and darker in color as opposed to the bright red color of fresh blood. Mucus, which is white or yellow in color, may also be passed in the stool. The blood and mucus may occur together, or there may be occasions where just mucus is passed along with a more formed stool.
Fever is a characteristic of the inflammatory process that takes place in UC. Fevers may be either high or low-grade and are present especially during periods of active disease (flare-ups). Night sweats are caused by a fever spiking repeatedly during the night.
Extra-intestinal symptoms are not directly related to the inflammation in the colon and include eye inflammation, joint pains, skin rashes or lesions, and mouth ulcers. Scientists are unsure why symptoms outside the colon occur, but they often decrease in severity along with flare-ups.
Eye conditions that can occur with UC include conjunctivitis, episcleritis, uveitis, and iritis. Most eye conditions will improve when progress is made in treating the underlying UC, but some may require treatment. Conjunctivitis, or “pink eye,” is an inflammation of the tissue covering the eye and inner surface of the eyelid and may be treated with antibiotics. Uveitis is the inflammation of the middle layer of the eye wall and symptoms include light sensitivity, pain, redness, blurred vision and headaches. Uveitis is commonly treated with corticosteroids; if left untreated it could result in glaucoma or detached retina. Inflammation in the white of the eye is called episcleritis, symptoms include pain and reddening, and treatment is with a vasoconstrictor or corticosteroid. Iritis is inflammation in the iris and symptoms include pain, light sensitivity, blurred vision, redness, decreased pupil size, and floaters. Steroids and antibiotics may be used to treat iritis.
Joint pains may be peripheral arthritis, which causes pain, swelling, and stiffness in the joints. The pain can migrate from one joint to the next and may last for several days or even weeks. Peripheral arthritis does not cause permanent damage to joints and will often improve when the UC is successfully treated. Treatment includes resting painful joints and applying moist heat. Other forms of arthritis may also occur with UC, and may be a complication of either the disease or the medications used to treat it.
Erythema nodosum, pyoderma gangrenosum and aphthous ulcers are skin conditions that may occur before or during a UC flare-up and improve with remission. Erythema nodosum are painful red nodules that develop on the arms or lower legs that affects more women than men. Pyoderma gangrenosum may appear as a blister on the legs or arms, usually at the site of a minor trauma such as a cut. The blister may progress into an ulcer that requires treatment with steroids or antibiotics. Aphthous ulcers are small ulcers in the mouth and although no treatment is usually necessary, prescription mouthwashes may help keep the area clean.
Are there different forms of UC?
Typically, inflammation from UC begins at the end of the digestive tract, in the rectum, and may spread up the colon. Unlike Crohn’s disease, UC does not skip around to different areas of the colon; the inflammation encompasses one entire section.
Physicians may use different terms to describe UC, depending on how much of the colon is diseased. Ulcerative proctitis is inflammation located in the rectum and symptoms include diarrhea, bloody stool, rectal pain, and an urgent need to move the bowels. Proctosigmoiditis is inflammation located in the rectum and sigmoid colon and symptoms include diarrhea, bloody stool, crampy pain, and pain on the left side of the abdomen. Left-sided colitis (also called limited or distal colitis) is inflammation in the left side of the colon (rectum and sigmoid and descending colon) and symptoms include diarrhea, bloody stools, weight loss, loss of appetite, and occasionally severe left-sided pain.
Pancolitis is inflammation throughout the whole colon and symptoms include diarrhea, cramps, significant weight loss and severe abdominal pain.
Ulcerative proctitis, proctosigmoiditis, and left-sided colitis may all be treated with medicines that are introduced through the anus such as a foam or suppository. Pancolitis must be treated with oral medication in order for the drugs to reach the entire colon and have the best effect.
What causes UC?
Scientists are not certain what causes UC, so it is known as an idiopathic disease, or a disease with unknown cause. However, there are several theories about the origins of UC and conditions that may contribute to its development.
UC (like Crohn’s disease) is an autoimmune disease, a disease that is triggered by the immune system. The medical community has noticed seasonal flare-ups in people with IBD. Some people experience problems only in the spring or autumn seasons. One theory is that this is a IgE-mediated allergic response.
IgE is a type of immunoglobulin isotype, which is a special protein that helps inactivate organisms that may cause disease. The function of IgE is to bind itself to an antigen and inactivate or remove offending toxins, microbes, or foreign substance. However, IgE tends to attach itself to receptors on mast cells which triggers allergy symptoms such as a runny nose. If an antigen binds itself to one of these IgE cells, the mast cells are activated, and release histamine, heparin, cytokines, leukotrines, and other chemicals.
The presense of leukotrines attracts a new type of cell called an eosinophil. These cells fight off the allergic response, but the chemicals that they use to do so are toxic to the body as well as to the invading infection. The connection between eosinophils and IBD is that three of the four toxic compounds that are released by eosinophil cells are found in in the stool of IBD patients.
A similar theory is that UC is caused by the immune system attacking the healthy bacteria found in the colon. Cells in the body called TH1 cells are responsible for initiating the immunologic response–the process that removes foreign bodies or unhealthy bacteria. Cells called TH2 cells tell the body to stop this process of removing any alien materials. In people with UC, the TH2 cells do not do their duty, which causes an attack on the billions of healthy bacteria living in the colon and results in an inflammatory response.
Scientists have also noticed a trend in the epidemiology of IBD. IBD tends to occur most often in Canada, the United States, Australia and western European countries. This leads researchers to think that there may be some connection between IBD and the lifestyles or environment of people living in these countries.
