November 30, 2009
Dr. Dustin Smith
Many people have small pouches in the lining of the colon that bulge outward through weak spots. Each pouch is called a diverticulum. Multiple pouches are called diverticula. The condition of having diverticula is called diverticulosis. About 10 percent of Americans older than 40 have diverticulosis. The condition becomes more common as people age. About half of all people older than 60 have diverticulosis.
When the pouches become inflamed, the condition is called diverticulitis. Ten to 25 percent of people with diverticulosis get diverticulitis. Diverticulosis and diverticulitis together are called diverticular disease.
Most people with diverticulosis do not have any discomfort or symptoms. However, some people may experience crampy pain or discomfort in the lower abdomen, bloating and constipation. Other conditions such as irritable bowel syndrome and stomach ulcers cause similar problems, so the symptoms do not always mean a person has diverticulosis. People with chronic symptoms should visit their doctor or health care provider.
The most common symptom of diverticulitis is abdominal pain. The most common sign on examination is tenderness in the lower left side of the abdomen. Usually, the pain is severe and comes on suddenly, but it also can be mild and become worse over several days. The intensity of the pain can fluctuate. A person may experience cramping, nausea, vomiting, fever, chills or a change in bowel habits.
Diverticulitis can lead to bleeding, infections, small tears or blockages in the colon. These complications always require treatment to prevent them from progressing and causing serious illness.
What causes diverticular disease?
Although not proven, the dominant theory is that a low-fiber diet causes diverticular disease. The disease was first noticed in the United States in the early 1900s, around the time processed foods were introduced into the American diet. Consumption of processed foods greatly reduced Americans' fiber intake.
Diverticular disease is common in developed or industrialized countries—particularly the United States, England and Australia—where low-fiber diets are consumed. The disease is rare in Asia and Africa, where most people eat high-fiber diets.
Fiber is the part of fruits, vegetables and grains the body cannot digest. Some fiber, called soluble fiber, dissolves easily in water. It takes on a soft, jelly-like texture in the intestines. Insoluble fiber passes almost unchanged through the intestines. Both kinds of fiber help prevent constipation by making stools soft and easy to pass.
Constipation—or hard stool—may cause people to strain when passing stool during a bowel movement. Straining may cause increased pressure in the colon, which may cause the colon lining to bulge out through weak spots in the colon wall. These bulges are diverticula.
Lack of exercise also may be associated with a greater risk of forming diverticula, although the reasons for this are not well understood. Doctors are not certain what causes diverticula to become inflamed. The inflammation may begin when bacteria or stool are caught in the diverticula. An attack of diverticulitis can develop suddenly and without warning.
To diagnose diverticular disease, the doctor asks about medical history, does a physical exam, and may perform one or more diagnostic tests. Because most people do not have symptoms, diverticulosis is often found through tests ordered for another ailment. For example, diverticulosis is often found during a colonoscopy done to screen for cancer or polyps or to evaluate complaints of pain or rectal bleeding.
A high-fiber diet and pain medications help relieve symptoms in most cases of diverticulosis. Uncomplicated diverticulitis with mild symptoms usually requires the person to rest, take oral antibiotics, and be on a liquid diet for a period of time. Sometimes an attack of diverticulitis is serious enough to require a hospital stay, intravenous antibiotics and possibly surgery.
Increasing the amount of fiber in the diet may reduce symptoms of diverticulosis and prevent complications such as diverticulitis. Fiber keeps stool soft and lowers pressure inside the colon so that bowel contents can move through easily. The American Dietetic Association recommends consuming 20 to 35 grams of fiber each day. The doctor may also recommend taking a fiber product one to three times a day.
Avoidance of nuts, popcorn, and sunflower, pumpkin, caraway, and sesame seeds has been recommended by physicians out of fear that food particles could enter, block or irritate the diverticula. However, no scientific data support this treatment measure. Eating a high-fiber diet is the only requirement highly emphasized across the medical literature. Eliminating specific foods is not necessary. The seeds in tomatoes, zucchini, cucumbers, strawberries and raspberries, as well as poppy seeds, are generally considered harmless. People differ in the amounts and types of foods they can eat. Decisions about diet should be made based on what works best for each person. Keeping a food diary may help identify what foods may cause symptoms.
If cramps, bloating and constipation are problems, the doctor may prescribe a short course of pain medication. However, some pain medications actually cause constipation.
Treatment for diverticulitis focuses on clearing up the inflammation and infection, resting the colon, and preventing or minimizing complications. Depending on the severity of symptoms, the doctor may recommend bed rest, oral antibiotics, a pain reliever, and a liquid diet. If symptoms ease after a few days, the doctor will recommend gradually increasing the amount of high-fiber foods in the diet.
Severe cases of diverticulitis with acute pain and complications will likely require a hospital stay. Most cases of severe diverticulitis are treated with IV antibiotics and a few days without food or drink to help the colon rest. In some cases, surgery may be necessary.
If symptoms of diverticulitis are frequent, or the patient does not respond to antibiotics and resting the colon, the doctor may advise surgery. The surgeon removes the affected part of the colon and joins the remaining sections. This type of surgery—called colon resection—aims to prevent complications and future diverticulitis. The doctor also may recommend surgery for complications such as a fistula or partial intestinal obstruction.
Immediate surgery may be necessary when the patient has other complications, such as perforation, a large abscess, peritonitis, complete intestinal obstruction or severe bleeding. In these cases, two surgeries may be needed because it is not safe to rejoin the colon right away. During the first surgery, the surgeon cleans the infected abdominal cavity, removes the portion of the affected colon, and performs a temporary colostomy, creating an opening, or stoma, in the abdomen. The end of the colon is connected to the opening to allow normal eating while healing occurs. Stool is collected in a pouch attached to the stoma. In the second surgery several months later, the surgeon rejoins the ends of the colon and closes the stoma.