Diverticulosis

What is diverticulosis?

The colon (large intestine) is a long tube-like structure that stores and then removes waste material. With increasing age in a person, pressure within the colon causes bulging pockets of tissue (sacs) that push out from the colon walls. A small bulging sac pushing outward from the colon wall is called a diverticulum. More than one bulging sac is referred to as diverticula. Diverticula can occur throughout the colon but are most common near the end of the left colon called the sigmoid colon. The condition of having these diverticula in the colon is called diverticulosis, also known as diverticular disease. This condition is uncommon before the age of 40 years, but its incidence increases after this age.

What are the causes?

Although not proven, a low-fibre diet is believed to be the main cause of diverticular disease. Lack of fibre in diet causes constipation, which in turn makes the muscles strain to move stool that is too hard. A diet without sufficient fibre also makes the stools small, requiring the bowel to squeeze harder to remove the smaller stool. This is the main cause of increased pressure in the colon. This excess pressure might cause the weak spots in the colon to bulge out and become diverticula. Diverticular disease is common in developed or industrialised countries—particularly the United States, England and Australia—where low-fibre diets are common. The disease is rare in countries of Asia and Africa, where people eat high-fibre vegetable diets. Fibre is the part of fruits, vegetables and grains that the body cannot digest. Some fibre dissolves easily in water (soluble fibre). It takes on a soft, jelly-like texture in the intestines. Some fibre passes almost unchanged through the intestines (insoluble fibre). Both kinds of fibre cause stools to retain more water and become easier to pass (either soluble or insoluble fiber will do this). Thus, we can broadly outline the factors that can cause diverticular disease as follows:

• A diet low in fibre content or high in fat
  
• Increasing age
  
• Constipation
  
• Connective tissue disorders, which can weaken the colon wall

What are the symptoms?

Whereas most patients with diverticular disease have no or few symptoms, some patients do develop bleeding, infection (diverticulitis), changes in bowel movements (diarrhoea or constipation), bloating, cramps (often in the left lower abdomen) after meals or otherwise and even colon obstruction.

Sometimes, symptoms include nonspecific chronic discomfort in the lower left abdomen, with occasional acute episodes of sharper pain. The discomfort is sometimes described as a general feeling of pressure in the region, or pulling sensation. A tickling sensation may be felt as the small pockets fill and unfill; a feeling like gas may be moving in areas outside the colon. At the first occurrence of bleeding, a doctor should be contacted.

How is it diagnosed?

Since most people do not have symptoms, diverticulosis is often found through tests ordered for another ailment. Colonoscopy is the most used test for diagnosis. Other tests include abdominal x-ray, barium enema, CT scan or MRI.

How is it treated?

Most often, diverticulosis requires no treatment. Increase in hydration by increasing fibre content in the diet or removing factors resulting in constipation helps decrease the incidence of new diverticula or possibly keep them from bursting or inflating. However, if there is an infection (diverticulitis), surgery is required to decrease relapse or other complications.