Diverticulosis and Diverticulitis

Diverticulosis and Diverticulitis Overview

What Is Diverticulosis?

Diverticulosis refers to the presence of small out-pouching’s (called diverticula) or sacs that can develop in the wall of the intestinal tract. They sort of resemble “pot-holes” in the lining. While diverticula can be present anywhere in the intestines, they are most common on the left side of the large intestine, or near the last part, in an area known at the descending and sigmoid colon.
How common is diverticulosis?

Diverticulosis is a common problem, especially in older people. The condition is uncommon in people under the age of 30, and is most common in those over 60.

Causes

What causes diverticulosis?

No one knows for sure why diverticulosis occurs; however, a few ideas have been suggested. Some experts believe that high pressure in the colon due to muscle spasm or straining may cause diverticula to form at weak spots in the colon wall. There appears to be a genetic predisposition to diverticulosis; that is, if your parent or brother or sister has diverticulosis, you may be more likely to develop it. Fiber in your diet may or may not play a role. Fiber is food such as fruits, vegetables and grains.

Symptoms

What are the symptoms of diverticulosis?

Most patients with diverticulosis have no problems or difficulties, and will never know they have the condition. They can be found during a procedure with a scope, or long flexible tube with a light and camera on the end, or an x-ray study. Some individuals may experience pain or discomfort in the left lower abdomen, gassy feeling, and/or a change in bowel habits, such as constipation or diarrhea.

Diagnosis

How is diverticulosis diagnosed?
Diverticulosis is generally discovered through one of the following examinations:
- Barium enema: This x-ray test involves putting liquid material into the colon through a tube placed in the rectum. The x-ray image shows the outline of the colon, and can identify if diverticula or abnormal growths are present.
- Colonoscopy: This test uses a thin, flexible tube with a light and camera to view the inside of the colon. Diverticula as well as other growths and other changes can be seen with this instrument.
- CT scan: This x-ray test takes multiple pictures of the body. It is not generally performed to locate diverticulosis, but it can see them.

Prevention

Can diverticulosis be prevented or eliminated?

It is not known whether diverticulosis can be prevented. Individuals who are overweight are more likely to have diverticulosis. Smoking may also increase the chance of developing diverticulosis. Therefore, maintaining a healthy weight and not smoking may prevent diverticulosis. Once diverticula have formed, they do not go away.
Can diverticulitis be prevented?

People with diverticulosis are sometimes asked to avoid foods such as popcorn, nuts, and seeds. However, a large study found that people who frequently ate nuts or popcorn were NOT more likely to experience diverticulitis, which is swelling and infection of the “pot-holes”, than those who did not eat these foods. Therefore, it is no longer recommended that people with diverticulosis or diverticulitis avoid these foods.

People who eat a diet high in fiber are less likely to develop diverticulitis than those who eat little fiber. Reducing the amount of red meat in the diet may also decrease the possibility of diverticulitis.
Studies show that people who maintain a healthy weight and exercise regularly are less likely to develop diverticulitis and diverticular bleeding than those who are overweight or who do not exercise. Not smoking is also likely to help prevent diverticulitis.
Decreasing the use of non-steroidal anti-inflammatory drugs, such as ibuprofen and aspirin, may decrease the chances of developing diverticulitis. However, if you take aspirin for your heart or blood vessels, you should not stop aspirin without talking to your doctor. Narcotic pain medicine and a type of steroid also appear to predispose to diverticulitis.
People who eat a diet high in fiber are less likely to develop diverticulitis than those who eat little fiber (although, as noted above, a high-fiber diet does not appear to decrease the chances of developing diverticulosis). Reducing the amount of red meat in the diet may also decrease the possibility of diverticulitis.
Studies show that people who maintain a healthy weight and/or exercise regularly are less likely to develop diverticulitis and diverticular bleeding than those who are overweight or who do not exercise. Avoiding smoking is also likely to help prevent diverticulitis, especially perforated diverticulitis.

Minimizing the use of non-steroidal anti-inflammatory drugs, such as ibuprofen and aspirin, may decrease the chances of developing diverticulitis. However, if you take aspirin for your heart or blood vessels, you should not stop aspirin without talking to your doctor. Opiate narcotics and corticosteroids also appear to predispose to diverticulitis.

Several different medications have been studied in hopes of preventing recurrent diverticulitis in patients who have had one or more attacks. Unfortunately, the best studied drug, mesalamine, has not reduced the likelihood of recurrent diverticulitis. There are only a few small studies on the use of probiotics (healthy bacteria) or rifaximin (a kind of antibiotic), so it isn’t clear if these medications might help reduce recurrent diverticulitis.

Complications

What are the complications of diverticulosis?
Diverticulitis is inflammation of one or a few diverticula in the colon. Diverticulitis occurs in less than 5 out of 100 people who have diverticulosis. People with diverticulitis typically have pain in the abdomen, usually on the lower left side. Other symptoms include fever, diarrhea and/or constipation, decreased appetite, nausea and fatigue.

People with diverticulitis can develop related complications including:
- Abscess – a collection of infected fluid outside of the intestine wall.
- Stricture –a narrowing of the colon in the area of diverticulitis.
- Fistula – a connection between the bowel and nearby organs including the bladder.
- Perforation – a hole in the colon that allows bowel contents, such as stool, to leak into the abdomen. This is the most serious complication of diverticulitis.
This occurs when a blood vessel that lines a diverticulum breaks open. Patients with this condition typically pass a large amount of red or maroon blood from the rectum. The bleeding tends to occur without warning and there is usually no abdominal pain. Most bleeding will stop on its own. However, examination of the colon with a scope may be necessary to diagnose and treat the bleeding. X-ray bleeding scans can also be used to identify the site of the diverticular bleeding if endoscopy does not or if bleeding is very severe. Occasionally, additional x-rays may be needed to identify and treat diverticular bleeding. In rare cases in which endoscopic or x-ray management fails to control the bleeding, surgery may be necessary.

Treatment

How is diverticulitis Treated?

Diverticulitis is typically treated with antibiotics and a liquid or light diet until symptoms improve. Some studies suggest that patients with mild diverticulitis who do not have complications, and are otherwise healthy, can be managed without antibiotics. People with severe diverticulitis (high fever, signs of severe infection) or with complications, require antibiotics and are usually treated in the hospital. X-ray guided drainage (via a tube placed in the abdomen) may be needed to drain large pus collections. Surgery may be needed for cases that do not respond to medical management or for patients with perforation.

Author(s) and Publication Date(s)

Ernst Bontemps, MD and Peter M. Pardoll, MD, FACG, Center for Digestive Diseases, South Pasadena, FL – Published June 2004, Updated September 2008.

Lisa L. Strate, MD, MPH, FACG, University of Washington School of Medicine, Seattle, WA – Updated 2016

John DeBanto, MD , Glendale, CA – Updated August 2022

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