Diverticulitis Overview

Diverticula are small pouches in the wall of the digestive tract. They occur when the inner layer of the digestive tract bulges through weak spots in the outer layer. (This is similar to what happens when an inner tube bulges through a tire.)

  • Although these pouches can occur any place from the mouth to the anus, most occur in the large intestine (colon), especially the left (lower) portion of the colon just before the rectum.
  • These marble-sized pouches usually occur where the blood vessels run through the intestinal wall.
  • Individuals who have these pouches are said to have diverticulosis.
  • Because this condition typically does not cause symptoms, most people are unaware that they have diverticulosis.
Picture of Diverticular Disease
Picture of Diverticular Disease

Diverticulitis vs diverticulosis

Diverticulitis is inflammation of diverticula. Diverticulitis occurs when one or more of these pouches becomes inflamed or infected. Some people with diverticulosis become aware of the condition only when acute diverticulitis occurs.

Diverticulosis is a very common condition in the United States.

  • Diverticulosis is mainly a condition of older people.
  • A smal percentage of Americans over the age of 40 have diverticulosis. As we age, the condition becomes more prevalent. Over half of people older than 60 years of age develop the condition, and about two-thirds of individuals older than 80 years of age are believed to have diverticulosis.
  • Only a few people with diverticulosis will develop diverticulitis.

Diverticulosis is more common in developed or industrialized countries.

  • In places such as the United States, England, and Australia, where the typical diet is low in fiber and high in highly processed carbohydrates, diverticulosis is common. The current theory is that a low-fiber diet may cause increased incidence of diverticular disease.
  • Diverticulosis first appeared in the United States in the early 1900s. This was about the same time when processed foods were first introduced into the U.S. diet.
  • Diverticulosis is much less common in countries of Asia and Africa, where the typical diet is high in fiber.

Most people recover from diverticulitis without complications if they receive appropriate treatment. Diverticulitis can lead to some very serious conditions if it is not detected and treated promptly. To a great extent, diverticulosis and diverticulitis can be prevented by changes in lifestyle and habits.

Diverticulitis Causes

Diverticulosis is thought to be caused by increased pressure on the intestinal wall from inside the intestine.

  • As the body ages, the outer layer of the intestinal wall thickens. This causes the open space inside the intestine to narrow. Stool (feces) moves more slowly through the colon, increasing the pressure.
  • Hard stools, such as those produced by a diet low in fiber or slower stool "transit time" through the colon can further increase the pressure.
  • Frequent, repeated straining during bowel movements also increases the pressure and contributes to the formation of diverticula.

Diverticulosis in developed countries is blamed largely on a diet low in fiber.

  • Fiber is found in fruits and vegetables, whole grains, and legumes (dried beans, peas, and lentils).
  • There are two types of fiber, soluble (dissolves in water) and insoluble.
  • Soluble fiber forms a soft gel-like substance in the digestive tract.
  • Insoluble fiber passes through the digestive tract nearly unchanged.
  • Both are necessary to keep stool soft and moving easily through the digestive tract, which helps prevent constipation.
  • This is how fiber prevents constipation.

Diverticulitis Symptoms

Most people with diverticulosis have no symptoms. When symptoms do occur, they are usually mild and include the following:

  • pain in the belly (abdomen),
  • bloating,
  • constipation (less often, diarrhea), and
  • cramping.

These symptoms are nonspecific. This means that similar symptoms are seen in many different digestive disorders. They do not necessarily mean that a person has diverticulosis. If an individual has these symptoms, he or she should see a health care practitioner.

Diverticulitis is a more serious condition and causes symptoms in most people with the condition that include:

  • pain in the abdomen, usually in the lower left side;
  • bleeding, bright red or maroon blood may appear in the toilet, on the toilet paper, or in the stool. Bleeding is often mild and usually stops by itself; however, it can become severe;
  • fever;
  • nausea;
  • vomiting;
  • chills; and
  • constipation (less often, diarrhea).

If diverticulitis is not treated promptly it can develop some very serious complications. A complication is suggested by any of the following symptoms:

  • worsening abdominal pain;
  • persistent fever;
  • vomiting (no food or liquid can be tolerated);
  • constipation for an extended period of time;
  • burning or pain during urination; and
  • bleeding from the rectum.

When to Seek Medical Care

If a person should see a health care practitioner if he or she has any of the following symptoms, which may indicate a serious condition:

  • persistent abdominal pain, often in the lower-left area of the abdomen;
  • persistent unexplained fevers;
  • persistent diarrhea;
  • persistent vomiting; or
  • persistent or recurring urinary tract infection.

Any time a person has bleeding from the rectum, he or she should see a health care practitioner as soon as possible.

  • Seek medical care even if the bleeding stops on its own.
  • Bleeding may be a sign of diverticulitis or other serious diseases.
  • If there is a lot of blood or a steady flow of blood, go to a hospital emergency department immediately.

The following symptoms suggest a complication and warrant an immediate visit to an emergency department:

  • worsening abdominal pain;
  • persistent fever with abdominal pain;
  • vomiting so severe that food or liquids cannot be tolerated;
  • swelling or distention of the abdomen;
  • persistent constipation for an extended period of time; or
  • severe pain or other symptoms that you had before when you had diverticulitis.

A person should not attempt to drive themselves to receive medical help, they should have someone else drive them, or call 911 for emergency medical transport. Calling for an ambulance often speeds the trip to the hospital when there is an emergency.

Diverticulitis Diagnosis

The health care practitioner will ask the patient questions about his or her symptoms, lifestyle and habits, and medical and surgical history.

  • The physical exam will probably include a "digital rectal examination" in which a health care practitioner inserts a gloved finger into the rectum to try to find a cause for bleeding or pain.
  • Blood tests may be performed to access signs of blood loss or infection, evaluate the function of the kidneys and liver, or to rule out other medical conditions that could be causing similar symptoms.
  • X-rays of organs in the abdomen may be ordered to assist in identifying the cause of the patient's symptoms.
  • CT scans are similar to an X-ray except they are able to visualize the organs better and often provide the health care practitioner with more useful information. One drawback with CT scans is that they are more expensive, and take longer to perform.
  • A colonoscopy is a procedure performed using a flexible tube with a tiny camera at the end, called an endoscope. The endoscope is inserted into the rectum and further up into the colon. The endoscope provides a direct view of the inner lining of the colon and rectum. The procedure is relatively painless and usually takes 30 to 45 minutes. Patients may be given a sedative medication to relax during the procedure.
  • A flexible sigmoidoscopy is a procedure performed with a flexible sigmoidoscope that has a tiny camera at the end of the sigmoidoscope. The patient lays on his or her left side while the instrument is inserted through the anus and advanced through the rectum and colon. This procedure is relatively painless and takes about five minutes.

Sometimes diverticulosis is discovered during a screening colonoscopy. The American Cancer Society and the United States Multi-Society Task Force on Colorectal Cancer recommend colonoscopies every 10 years for people older than 50 years to detect early signs of colon cancer. If an individual's family medical history includes a close relative diagnosed with colon cancer, they may need to begin screening at an earlier age. Consult a gastroenterologist for guidelines.

Diverticulitis Self-Care at Home

These measures may help and prevent new diverticula from forming.

  • Eat a high-fiber diet. High-fiber foods include fruits, vegetables, whole grains, and dried beans, peas, and lentils. These foods contain elements that your body cannot digest and are passed through your colon.
  • Drink plenty of fluids to help keep stools soft and prevent constipation.
  • Get plenty of physical activity to keep bowels functioning properly.

Diverticulitis Medical Treatment

Diverticulosis with symptoms is usually treated as follows. This therapy is designed to soften stools and help them pass faster, which removes the conditions that cause diverticula in the first place.

  • High-fiber diet: Some health care practitioners recommend a fiber supplement to prevent constipation.
  • Clear fluids
  • Mild pain medications

Treatment for diverticulitis depends on the severity of the condition.

  • Simple cases can be treated by a health care practitioner at his or her office.
  • Treatment for uncomplicated cases usually consists of antibiotics and bowel rest. This usually involves two to three days of bowel rest, taking in only clear fluids (no food at all), so the colon may heal without having to work.
  • Complicated cases typically involve severe pain, fever, or bleeding. If an individual has any of these symptoms, he or she will probably be admitted to the hospital. Treatment consists of IV antibiotics, bowel rest, and possibly surgery.

Diverticulitis Surgery

If diverticulitis attacks are frequent or severe, the doctor may suggest surgery to remove a part of the patient's colon.

  • As with any surgery, there are risks that the patient should discuss with his or her physician.
  • Sometimes the operation requires at least two separate surgeries on different occasions.

Diverticulitis Diet

A high-fiber diet is the mainstay of diverticulosis and diverticulitis prevention.

  • Starting a high-fiber diet may not make the diverticula a person has go away, but it will decrease the risk of complications and the accompanying symptoms.
  • Foods high in fiber include whole-grain cereals and breads, fruits (apples, berries, peaches, pears), vegetables (squash, broccoli, cabbage, and spinach), and dried beans, peas, and lentils.
  • Drinking plenty of fluids will also help the stool stay soft and pass quickly, decreasing the risk for diverticulosis.

There has been debate over whether those with diverticulosis or diverticulitis should be advised to avoid foods such as nuts, corn, and popcorn. A 2008 study published in the The Journal of the American Medical Association found these foods may actually lower risk of the condition because of their high fiber content. Consult a health care practitioner for the dietary recommendations.

Diverticulitis Follow-Up

Eating a high-fiber diet will not only decrease a person's chance of getting diverticulitis; it will benefit health in other ways such as by lowering the risk of colon cancer and possibly heart disease.

In a significant number of people, diverticulitis recurs after it has been treated. The second episode may be worse than the first. See a health care practitioner at the first sign of recurring symptoms.

Diverticulitis Prevention

As mentioned previously, a high-fiber diet is the mainstay of diverticulosis and diverticulitis prevention.

Diverticulitis Prognosis

Most people recover fully after treatment. If not treated promptly, however, diverticulitis can lead to the following more serious conditions:

  • Perforation: A hole in the intestine caused when the diverticular pouch bursts because of increased pressure and infection within the intestine.
  • Peritonitis: A more serious infection of the abdominal cavity that often occurs after perforation, when the contents of the intestine leak out into the abdominal cavity (peritoneum) outside of the intestine.
  • Abscess: A pocket of infection that is very difficult to cure with antibiotics.
  • Fistula: An abnormal connection between the colon and another organ that occurs when the colon damaged by infection comes in contact with another tissue, such as the bladder, the small intestine, or the inside of the abdominal wall, and sticks to it. Fecal material from the colon can then get into the other tissue. This often causes a severe infection. If fecal material gets into the bladder, for example, the resulting urinary tract infection can become recurrent and very difficult to cure.
  • Blockage or obstruction of the intestine
  • Bleeding in the intestine

Individuals younger than 40 years of age who have depressed immune systems from medications or other illnesses have a greater chance of having complications and having to undergo surgery.

Approximately one-half of people who have diverticulitis will have a relapse within seven years after the condition is treated and in remission.

Of the people who are admitted to a hospital for diverticulitis, some develop complications that require surger

Topic Overview

Lower digestive system

What is diverticulitis?

Diverticulosis happens when pouches (diverticulaClick here to see an illustration.) form in the wall of the colonClick here to see an illustration.. If these pouches get inflamed or infected, it is called diverticulitis. Diverticulitis can be very painful.

What causes diverticulitis?

Doctors aren't sure what causes diverticula in the colon (diverticulosis). But they think that a low-fiber diet may play a role. Without fiber to add bulk to the stool, the colon has to work harder than normal to push the stool forward. The pressure from this may cause pouches to form in weak spots along the colon.

Diverticulitis happens when feces get trapped in the pouches (diverticula). This allows bacteria to grow in the pouches. This can lead to inflammation or infection.

What are the symptoms?

Symptoms of diverticulitis may last from a few hours to a week or more. Symptoms include:

  • Belly pain, usually in the lower left side, that is sometimes worse when you move. This is the most common symptom.
  • Fever and chills.
  • Bloating and gas.
  • Diarrhea or constipation.
  • Nausea and sometimes vomiting.
  • Not feeling like eating.

How is diverticulitis diagnosed?

Your doctor will ask about your symptoms and will examine you. He or she may do tests to see if you have an infection or to make sure that you don't have other problems. Tests may include:

How is it treated?

The treatment you need depends on how bad your symptoms are. You may need to have only liquids at first, and then return to solid food when you start feeling better. Your doctor will give you medicines for pain and antibiotics. Take the antibiotics as directed. Do not stop taking them just because you feel better.

For mild cramps and belly pain:

  • Use a heating pad, set on low, on your belly.
  • Relax. For example, try meditation or slow, deep breathing in a quiet room.
  • Take medicine, such as acetaminophen (Tylenol, for example).

You may need surgery only if diverticulitis doesn't get better with other treatment, or if you have problems such as long-lasting (chronic) pain, a bowel obstruction, a fistula, or a pocket of infection (abscess).

How can you prevent diverticulitis?

You may be able to prevent diverticulitis if you drink plenty of water, get regular exercise, and eat a high-fiber diet. A high-fiber diet includes whole grains, fresh fruits, and vegetables.