As a person grows older, pouches of tissue may form outside the walls of the large intestine, or colon. These are referred to as diverticula, or diverticulum in singular form. These sacs are the defining characteristic of two colon diseases or intestinal disorders: diverticulosis and diverticulitis. Although they share several similarities, they also have a few differences.

The diverticula occur at the sigmoid colon, which is the lower region of the large intestine. The very presence of diverticula denotes diverticulosis. It is only when the diverticula become inflamed that the condition develops into diverticulitis. Still, diverticulosis and diverticulitis are lumped together under the term "diverticular disease."

The cause of diverticulosis and diverticulitis is yet to be determined. The prevailing theory, however, is that people with low-fiber diets are more likely to develop colon pouches. Diverticulosis and diverticulitis are prevalent in the Western world, which is dominated by low-fiber diets. It is less so in Africa and Asia, where the cuisine usually consists of a high level of fiber.

Although there might be some signs such as bloating, constipation and faint cramps, people with diverticulosis do not typically show any significant symptoms. Those with diverticulitis, however, will experience sharp pains in the abdomen. Some patients may experience bleeding as well, if blood vessels in the diverticula burst, although this is a rare occurrence.

Diverticulitis is considered a more serious condition than diverticulosis, especially if an infection is involved. In such cases, other signs occur, such as cramping, vomiting, nausea and a false feeling of fever. This indicates a progression of the infection, marked by a development of accumulations of pus from the colon. This condition, known as peritonitis, could kill the patient if not promptly attended to.

Physicians diagnose diverticulosis and diverticulitis using medical imaging techniques such as ultrasound and computerized tomography (CT) scan. Regarding patients who have diverticulosis, doctors focus on preventing the condition from developing into diverticulitis by recommending a diet high in fiber. The dietary regimen may also consist of fiber products that contain chemical compounds such as methylcellulose to fight constipation.

Diverticulitis, however, requires the reduction of the colon's inflammation and infection. Additionally, the patient may be restricted to a liquid diet for a certain period of time. In the most extreme instances, the doctor would have to administer intravenous (IV) antibiotics, demand a hospital stay, cut off the patient from ingestion of food and drink for a few days, or perform surgery to remove the affected area of the colon.