Rectal bleeding and diseases of the colon

Rectal bleeding is a common occurrence in diseases of the colon. Bleeding from the rectum through the anus is a serious symptom that must not be taken lightly. There are some common diseases, which are associated with this condition. Of more important consideration is the fact that these diseases are associated with certain complications of which cancer of the colon is the most deadly.

The colon, also referred to as the large intestine is that portion of the gastrointestinal tract that stretches from the caecum (where the small intestine ends) to the rectum and then the anus which is the outlet. The large intestine is divided into the ascending, transverse and descending colon. This is the portion of the gastrointestinal tract that has to do with the regulation of water in response to the level of hydration in the body. When there is enough water in the body, water is not reabsorbed and the stools, which are stored in the rectum remain soft.

However, when the body is dehydrated, water is reabsorbed from the stools in a bid to improve the hydration status of the body. This leaves the stools hard, slow moving and difficult to pass out. Having reabsorbed water from the stools, the undigested food and waste matter, which make up the stools remain in the rectum until they are passed out. Stools that are stored in the rectum begin to undergo bacterial action with the release of toxins and acids. Depending on the hydration status and how long the stools remain in the rectum a lot of toxins and acids can be released. These toxic substances can cause damage of the lining of the colon locally or can be carried to distant locations where they can give rise to conditions like cancer. More often than not, the local damage that arises as a result of the toxins can lead to bleeding, inflammation and ulcer in the colon.

Causes of rectal bleeding
Common causes of rectal bleeding include hemorrhoids, proctitis, fissures, ulcerative colitis, Crohn’s disease, diverticulosis, ischaemic colitis, rectal trauma and cancer of the colon.

We are going to spend some time looking at these diseases and how the rectal bleeding can help us arrive at a diagnosis. We shall also be looking at the right diet and water that will ensure the wellbeing of the colon. This is very important because, diseases associated with the colon that were foreign to us in Africa are now being encountered here. Not only that, there are some other diseases that are associated with those of the colon and right knowledge of these conditions will assist in making the right diagnosis. We have already discussed hemorrhoids in last Thursday’s edition of The Guardian Newspaper. Today we shall be discussing ulcerative colitis, which together with Crohn’s disease make up the group called inflammatory bowel disease (IBD).

Ulcerative colitis
This is a chronic inflammatory disease of the colon. In patients with ulcerative colitis, the inner lining of the rectum and upper part of the large intestine away from the rectum are usually covered by the inflammatory reaction and ulcers. This condition of the inner lining of the colon gives rise to such symptoms as abdominal pain, rectal bleeding and frequent stooling (diarrhoea). The stools passed are frequently mixed with blood and mucus.

Cause of ulcerative colitis
The cause of ulcerative colitis is unknown. However, there are theories associated with it. These theories connected to the cause(s) of ulcerative colitis include genetic causes, alteration of the normal bacterial flora of the intestines [as seen in too frequent use of antibiotics], diet, environmental factors and hyperactivity of the immune system.