Diverticulosis is the medical description for the presence of diverticula in the colon.
A diverticulum involves a small pouch being formed as a part of the inner intestinal lining pushes through muscular outer layer of the intestine, leading to a narrow-necked pouch.
Diverticula mostly occur in the colon on the lower left side and diverticulosis is the term when many are present in the gut.
What is the cause of diverticula? A diverticulum can occur naturally and this is most likely in the small intestine, with a majority of British people over seventy years of age having diverticula in the large intestine.
Diverticula increase in incidence with the years and are much commoner in later life.
Incidence of diverticula is lower in rural parts of the world such as Africa although the reasons for this are not clear.
Diet may well be an important difference between rural countries and western developed countries due to the colon's function of processing the typical plant foods which are relatively indigestible.
Fibre rich materials form a much smaller proportion of western countries' diets compared to the mostly vegetarian other parts of the world.
The bulk of intestinal contents maintains the shape of the colon if the diet has the right levels of fibrous material to allow it to function well.
Firmer and harder stools result from low levels of dietary fibre and when the colonic walls tighten the reduced contents fail to adequately keep the walls apart.
The ring like contractions move and mix the contents along the colon and there can be closed sections where the pressure is much higher than normal, perhaps leading to pouch formation.
Is there any harm in having diverticula? An appendix is a form of diverticulum in some ways and is not the cause of anxiety.
Many people have a colon with many diverticula protruding from its walls, are unaware of them and they are not problematic in any way.
The appendix can however become inflamed and so can diverticula, often from infection.
This can cause pain locally when it occurs, make someone feel unwell and can be medically risky if it should bleed or perforate.
Diverticulitis is the name given to inflammation of one or many diverticula.
What is diverticular disease? In most people with diverticula the intestinal muscle is normal in appearance and thickness, but in some people it becomes thicker than normal and has an unusual structure under the microscope.
The thickening of the muscle narrows the colon which becomes irregular in outline.
The reason for this is not known but it is important to realise that it is not due to infection and may not be related to diet.
The muscle abnormality can develop when very few diverticula are present and occasionally it occurs without any diverticula.
The combination of abnormal muscle and diverticula is known as diverticular disease.
This is confusing because diverticula and diverticular sound the same, hence the use of the word disease.
Diverticular disease symptoms The symptoms of diverticular disease include an irregularity of bowel habit with pellet like stool, bowel actions with blood passed with them, wind and bloating and pain in the abdomen down the lower left side.
Irritable bowel syndrome has similar symptoms to diverticular disease perhaps secondary to both problems involving functional muscle abnormality.
Is investigation necessary? When conditions such as bleeding rectum or pain in the abdomen are investigated by endoscopy (sigmoidoscopy or colonoscopy) or x-ray barium enemas then diverticula are often discovered as a side effect.
Elderly people who are well typically have diverticula so their importance as to the cause of the symptoms or not is important to establish.
Evidence of inflammation on blood tests and tenderness of the diverticular area indicate the diagnosis is diverticular disease.
The increased folds in the left, lower colon lining which can be present are the abnormal muscle finding in diverticular disease.
Explaining the situation People worry about the presence of a more serious condition so reassurance is important.
Some symptoms are due to infections and others due to muscular contraction abnormalities in the absence of inflammation.
The difference explains the differences in the pros and cons of choosing various treatments.