New hope for those with diverticular disease

New Hope for Those with Diverticular Disease

As the U.S. population grows older,experts have warned, Americans can expect to suffer from an increasing number of health problems. In recent years, however, attention has turned to the possibility that most Americans--by changing their lifestyles--may be able to avoid or control many of the diseases traditionally associated with aging, if they act in time.

One condition associated with agingfor which new hope has emerged in recent years is diverticular disease--inflammation or infection of the large intestine, or colon. Diverticular disease rarely touches people under 40. But more than half of Americans have it by the time they reach 60.

Most people with a milder form of diverticulardisease--a condition called diverticulosis --aren't aware they have it because they experience no symptoms. However, when it progresses to diverticulitis, they may suffer a variety of symptoms, including severe pain. Diverticulitis may lead to dangerous bowel complications requiring hospitalization and even major surgery. Though the disease itself is rarely fatal, complications from diverticulitis can cause death.

Diverticular disease consists of smallsacs of grape-like protrusions formed when the lining of the intestine is forced out through the gut's muscular wall. The lesions may occur anywhere in the gut, but are found mostly in the colon. Doctors call them diverticula--or a diverticulum when there is only one. (It's from the Latin verb divertere, which means to turn aside.) These small, self-contained hernias of the colon wall vary in size from a fraction of an inch to slightly over an inch in diameter.

The small hernias in the gastrointestinaltract that give rise to diverticula usually occur in the last segment, called the sigmoid (for S-shaped), or descending, colon. So, to understand how diverticula develop, it's helpful to see how the large intestine functions.

The colon--five to seven feet long andthree to four inches in diameter--is composed, in part, of two sets of muscles. One set runs lengthwise in three roughly parallel lines. The other encircles the colon in parallel rings, giving the organ a bumpy appearance like that of a long balloon ringed by strings that partially restrict its cross-section every inch or so.

The colon receives watery, undigestedmaterial from the small intestine. Acting in concert, the two sets of muscles push this residue from one end to the other in wave-like, squeezing motions. In the process, the colon wall may contract and expand up to 10 times a minute. As the undigested material moves through the colon, some vitamins, water and minerals are absorbed into the bloodstream. Finally, bacteria break down the residue before it is expelled through the rectum.

In diverticulosis, the colon contractsand its walls tend to thicken. This is particularly true of the sigmoid, the narrowest and most muscular section. The normally pillow-like external convolutions may take on a corrugated appearance instead. This process of constriction occurs as the sigmoid exerts more pressure on its contents. This added pressure is probably one of the causes of diverticula, although researchers are far from certain about how diverticulosis begins.

Weak spots often form in the intestinalwall--particularly along the corrugated ridges of the colon. At these weak spots, diverticula made up of mucous membrane and connective tissue may balloon through the muscle wall like bubblegum from the mouth of a child. They usually occur where arterioles--small arteries-- enter the colon through small gaps in the muscle wall. Occasionally these arterioles balloon out with the diverticula.

According to one estimate, of the millionswho harbor diverticula, only one in five will develop symptoms or become sick. Those with symptoms may complain of occasional nausea, constipation, gas, bloating and, sometimes, pain. (These same symptoms can arise from other diseases, such as irritable bowel syndrome, gastric ulcer, hiatal hernia, and liver disease.)

Physicians have two ways to diagnosediverticular disease: the diverticula can be seen on a barium enema X-ray of the lower digestive tract, and the tiny telltale hernias inside the colon wall often can be detected by examination with an endoscope --a flexible fiber device for seeing inside hollow organs of the body.

Physicians use such diagnostic proceduresto follow up many gastrointestinal complaints. For example, sigmoidoscopy, an endoscopic examination of the sigmoid colon, is often part of routine physical checkups, particularly in middle-aged men, who tend to suffer a higher incidence of colon cancer. So diverticula may be discovered during routine physical examinations or as physicians diagnose other problems of the digestive tract.

When diverticula become inflamed,diverticulosis turns into diverticulitis. The likelihood of developing this inflammatory complication rises if diverticula are numerous or widely distributed in the colon, if they appear at an early age, or if they have been present 10 years or longer.