:: Large intestine

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Some common conditions affecting the Large Intestine.

• Inflammatory Bowel Disease (IBD) Ulcerative colitis and Crohn's disease.
  
  
• Diverticular disease
  
  
• Colorectal Cancer

Inflammatory Bowel Disease (IBD) Ulcerative colitis & Crohn's disease.

Ulcerative colitis and Crohn's disease are two types of inflammatory bowel disease -
a condition which causes the bowel (colon) to become inflamed and red. Both conditions can affect parts of the body outside the bowel and may be associated wit h poor general health.

Inflammatory bowel disease is a totally different condition from irritable bowel syndrome (IBS) where the functioning of the bowel is affected but it looks normal in appearance.

Ulcerative colitis and Crohn's disease are long-term, chronic (ongoing) conditions which can flare up on and off throughout life.

Most commonly, the symptoms of ulcerative colitis include:

• abdominal pain;
• blood, mucus or pus in the stool;
• diarrhoea;
• fatigue and tiredness;
• weight loss; and
• loss of appetite.

People with ulcerative colitis may also develop other symptoms unrelated to the bowel. These can include mouth ulcers, skin problems, joint pains, and eye or liver problems.
Most of the time many people with ulcerative colitis feel well and don't have symptoms. This means the disease is not 'active' at this time, or can be said to be in remission. However, when the disease flares up and causes symptoms, this is known as a relapse.
Most of the time a 'trigger' for a relapse can't be identified, although some people find that stress, infections, some medications or certain foods bring on an attack. It should be remembered that none of these is the cause of the disease itself.

Depending on where the inflammation occurs in the large bowel, ulcerative colitis can also be called proctitis (involving the rectum only), proctosigmoiditis or distal colitis (involving the rectum and sigmoid colon), or universal or pan-colitis, which means the entire colon is affected. Doctors don't know why some people's disease spreads to involve their entire colon yet in others the disease is confined to one area of it.

Causes of Ulcerative Colitis and Crohn's disease

Unfortunately the cause is still unknown despite intensive research. Causative factors that have been suggested include:

• genetic predisposition;
• infectious agents (bacteria and viruses);
• Drugs
• Smoking
• Psychogenic factors
• defects in the immune system; and
• environmental factors.

Some doctors suggest a combination of some or all of these factors may be involved. Psychological stress and food allergies are not thought to play a role in development of the disease, but they may aggravate symptoms in some people.


Diagnosis

Ulcerative colitis and Crohn's disease are sometimes difficult to diagnose because its symptoms can be similar to other conditions such as bowel infections or irritable bowel syndrome. Most people with the disease will generally need a colonoscopy, sigmoidoscopy, barium meal or barium enema to confirm the diagnosis.
Blood tests can reveal whether you have anaemia or any vitamin or mineral deficiencies.

Inflammatory Bowel Disease and cancer

If you have widespread ulcerative colitis, your risk of developing colon cancer is higher than people who do not have ulcerative colitis. This is particularly true if you have had colitis for many years.

Your doctor will probably advise you to have regular examination by colonoscopy. A biopsy (small tissue sample) will probably be taken at the colonoscopy for microscopic examination to detect any changes in bowel tissue that might lead to cancer. Your doctor will advise you on how often you should have these examinations depending on how long you have had the ulcerative colitis.

Diverticular disease

Diverticular disease is a common condition with only a small percentage of those with the disease have symptoms, and even fewer will ever require surgery.
Diverticula are pockets that develop in the colon wall, may involve the entire colon but usually in the sigmoid or the descending colon. Diverticulosis describes the presence of these pockets. Diverticulitis describes inflammation or complications of these pockets.

Symptoms

The major symptoms of diverticular disease are abdominal pain (usually in the lower left abdomen), diarrhoea, cramps, alteration of bowel habit and occasionally, severe rectal bleeding. These symptoms occur in a small percentage of patients with the condition
and are sometimes difficult to distinguish from Irritable Bowel Syndrome.
Diverticulitis - an infection of the diverticula - may cause one or more of the following symptoms: pain, chills, fever and change in bowel habits. More intense symptoms are associated with serious complications such as perforation, abscess or fistula formation.

Causes

Exact cause of the diverticular disease is not known, but there are indications are that a low-fibre diet over the years creates increased colon pressure and results in pockets or diverticula. Diverticular disease is unknown in rural Africans who eat a high fibre diet, but is common in western societies where many people have a low fibre intake. It is much less common in vegetarians.

Treatment

Diverticulosis and diverticular disease are usually treated by diet and occasionally, medications to help control pain, cramps and changes in bowel habits. Increasing the amount of dietary fibre (grains, legumes, vegetables, etc.) - and sometimes restricting certain foods reduces the pressures in the colon, and complications are less likely to arise.

Diverticulitis requires more intense management. Mild cases may be managed without hospitalisation, but this is a decision made by your doctor.
Treatment is aimed at resting the bowel, relieving pain and fighting infection. A low-fibre, or fluid-only diet, is recommended to rest the bowel.

Severe cases require hospitalisation with intravenous antibiotics and strict dietary restraints. Most acute attacks can be relieved with such methods.

Surgery is reserved for recurrent episodes, complications or severe attacks when there's little or no response to medication.
In surgery, usually part of the colon - commonly the left or sigmoid colon - is removed along with a small part of the normal colon and the ends of are hooked up or "anastomosed" again to the rectum. Complete recovery can be expected. Normal bowel function usually resumes in about three weeks.

It is wise to visit a dietitian/nutritionist after being diagnosed with diverticular disease.

Colorectal cancer

Colorectal cancer is currently the second most common internal malignancy affecting 1 in 20 Australians; prostate cancer is more common in men and breast cancer more common in women.
Symptoms:

• Rectal bleeding
• Altered bowel habit
• Iron deficiency anaemia
• Abdominal pain
• Unexplained weight loss

There may be no symptoms until the cancer is advanced.

Colonoscopy is the most appropriate investigation in terms of diagnosis and treatment as nearly all bowel cancers start out as polyps. If these are removed the risk of cancer developing in that polyp is also removed.
Mortality has not changed substantially over the past twenty years and we need to improve awareness of symptoms, the importance of early diagnosis, and the benefits of surgery for early cancer

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