Illness & Conditions - Health Conditions
What is diverticulitis?
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:
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:
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.
Frequently Asked Questions
Diverticulitis develops when feces become trapped in pouches ( diverticula ) that have formed along the wall of the large intestine. This allows bacteria to grow and cause an infection or inflammation and pressure that may lead to a small perforation or tear in the wall of the intestine. Peritonitis , an infection of the lining of the abdominal wall, may develop if infection spills into the abdominal (peritoneal) cavity.
The reason diverticula form in the wall of the large intestine (colon) is not completely understood. Doctors think diverticula form when high pressure inside the colon pushes against weak spots in the colon wall. Uncoordinated movements of the colon can also contribute to the development of diverticula.
Normally, a diet with adequate fiber (also called roughage) produces stool that is bulky and can move easily through the colon. If a diet is low in fiber, the colon must exert more pressure than usual to move small, hard stool. A low-fiber diet also can increase the time stool remains in the bowel. This adds to the high pressure. Pouches may form when the high pressure pushes against weak spots in the colon where blood vessels pass through the muscle layer of the bowel wall to supply blood to the inner wall.
It is not known why some people who have these diverticula (a condition called diverticulosis ) develop diverticulitis and others do not.
Symptoms of diverticulitis may last from a few hours to several days. These symptoms may include:
Complications also can cause symptoms. If an abnormal opening (fistula) develops between the colon and the vagina or the colon and the urethra , you may pass air or stool from the vagina or the urethra.
Diverticulitis occurs when pouches ( diverticula ) that have developed in the wall of the large intestine (colon) become inflamed or infected. It is not clearly understood why 20 out of 100 people who have these pouches—a condition called diverticulosis —develop diverticulitis and the others do not.
In Western countries (North America and Europe), diverticulitis usually affects the left side of the colon (sigmoid colon).
Mild attacks of diverticulitis, with few symptoms or signs of infection or inflammation, sometimes heal without treatment. In most cases, a doctor recommends oral antibiotics to resolve an infection and a clear liquid diet to rest the bowel until inflammation goes away.
When infection and symptoms are severe, diverticulitis is treated in the hospital. Treatment includes antibiotics given in a vein (intravenous, or IV) and resting the bowel with IV fluids. If severe diverticulitis is not treated, complications such as an abscess or fistula may develop. Surgery often is needed to treat complications.
It is common to have lower abdominal pain after recovering from an attack of diverticulitis. But this pain is not always a return of diverticulitis. Less than half of people ever have a second diverticulitis attack. Of those who do have another attack, about half have the second attack within 1 year of their first one. 1
What Increases Your Risk
The possibility of having diverticulitis increases with age.
You may be more likely to develop diverticulitis if you:
When To Call a Doctor
Call 911 or other emergency services immediately if the person has been bleeding from the anus and has signs of shock , which could mean that a diverticular pouch is bleeding ( diverticular bleeding ). Signs of shock include passing out, or feeling very dizzy, weak, or less alert.
Call your doctor immediately if you have pain in the abdomen that is in one spot (as opposed to general pain in the abdomen), especially if you also have:
Call your doctor immediately if you have:
Call your doctor if you:
Call your doctor if you are treating mild diverticulitis at home and:
It is not uncommon to have bloating, gas pressure, or mild abdominal (belly) pain. These can be caused by eating certain foods or by stress. Home treatment usually will take care of these symptoms. If home treatment does not help or if the symptoms become worse, see your doctor.
Who to see
Health professionals who can diagnose and prescribe treatment for diverticulitis include:
If further tests are needed, if your symptoms do not respond to treatment, or if you may need surgery, your doctor may refer you to a:
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
Your doctor will take a history and do a physical exam if diverticulitis is suspected. Depending on your symptoms, you may have one or more tests to rule out other medical problems that could be causing your symptoms. The extent of testing will depend on how bad your symptoms are and how long they have lasted.
These tests may be done any time you see your doctor about abdominal pain or other symptoms.
Tests done as needed
Depending on your symptoms, your doctor may want to do one or more of these tests.
If you are having serious bleeding from the intestine, a condition called diverticular bleeding, your doctor may want to do:
See the topic Diverticular Bleeding for more information.
You may have a brief (acute) bout of diverticulitis that goes away after treatment with antibiotics and a liquid diet. But in some cases the condition occurs off and on (intermittently) over the long term (chronic). Treatment is the same in both cases, unless complications occur.
Treatment for diverticulitis depends on how bad your symptoms are. If the pain is mild, you are able to drink liquids, and you have no signs of complications, treatment may include:
If the pain is severe, you are not able to drink liquids, or you have complications of diverticulitis, a hospital stay is needed. Treatment will include:
Treatment may also include:
Most cases of promptly treated diverticulitis will improve in 2 to 3 days. If your doctor prescribed antibiotics, take them as directed. Do not stop taking them just because you feel better.
Treatment after recovery from an attack of diverticulitis is aimed at preventing another attack. Treatment may include:
Treatment if the condition gets worse
In some cases, complications of diverticulitis, such as an abscess, perforation, or bowel obstruction, can occur. Surgery to remove the affected part of the intestine usually is needed to treat these conditions.
Nonurgent (elective) surgery also may be done for diverticulitis if you have had two or more severe attacks, are younger than age 40, or have an impaired immune system .
To help prevent diverticulitis:
Some people avoid nuts, seeds, berries, and popcorn, believing that these foods might get trapped in the diverticula and cause pain. But there is no evidence that these foods cause diverticulitis or make it worse. 4
Home treatment may help you control symptoms of diverticulitis or reduce the chance of having additional attacks of diverticulitis.
To reduce abdominal pain caused by mild diverticulitis:
When you are feeling better, you can do some things to help prevent another attack. You may want to:
Do not use laxatives or enemas unless your doctor prescribes them. If you use laxatives too often, you can become dependent on them for bowel movements. If you are having a sudden (acute) attack of diverticulitis, laxatives or enemas can make the pain worse.
Medicines to stop infection and to control symptoms often are used to treat attacks of diverticulitis.
What to think about
Medicines are not used to prevent future attacks of diverticulitis. Prevention depends on increasing the amount of fiber in your diet and practicing healthy bowel habits.
Surgery for diverticulitis involves removing the diseased part of the colon. You may decide to have surgery for diverticulitis if you have:
Surgery for diverticulitis, in which the infected part of the colon is removed, may be required if you have complications, including:
Overall, fewer than 6 out of 100 people who have diverticulitis need surgery. 3
Surgical treatment involves removing the diseased part of the large intestine ( partial colectomy ) and reconnecting the remaining parts. Depending on the severity and nature of the symptoms, more than one surgery may be needed to correct the problem. When multiple surgeries are needed, the person usually has a colostomy during the time between surgeries. A colostomy is a surgical procedure in which the upper part of the intestine is sewn to an opening made in the skin of the abdomen. Stool passes out of the body at this opening and into a disposable bag. Usually the colostomy is removed at a later time and the intestine is reconnected.
Surgical treatment of diverticulitis, called bowel resection, involves the removal of the diseased part of the large intestine.
What to think about
People who have mild, brief attacks and who are willing to try long-term dietary changes may be able to avoid surgery. See the Prevention section of this topic for more information on diet.
If you have multiple attacks of diverticulitis, surgery may be appropriate.
Draining an abscess
In some cases of diverticulitis, a pocket of infection ( abscess ) in the abdomen heals on its own. At other times it can be drained without surgery. A needle is passed through the skin into the abscess, and the liquid containing the infection is drained. A computed tomography (CT) scan is used to help the doctor guide the needle into the abscess. Sometimes a plastic drain is placed temporarily in the abdomen to drain the abscess.
A blocked colon can sometimes be treated with bowel rest. You are not given anything to eat but instead receive fluids and nutrients through a tube connected to a vein. Suction through a tube placed in the nose and down into the stomach may be needed to keep the stomach emptied of digestive juices.
After 2 to 3 days of bowel rest, you are given something to eat. If the obstruction has cleared up, no surgery is needed. If the obstruction remains, bowel rest may be continued. If repeated periods of bowel rest fail to clear up the obstruction, surgery to remove the diseased part of the colon may be considered.
Other Places To Get Help
Last Revised: July 19, 2012
Author: Healthwise Staff
Humes D, et al. (2011). Colonic diverticular disease, search date May 2010. BMJ Clinical Evidence. Available online: http://www.clinicalevidence.com.
Strate LL, et al. (2011). Use of aspirin or nonsteroidal anti-inflammatory drugs increases risk for diverticulitis and diverticular bleeding. Gastroenterology, 140(5): 1427–1433.
Harford WV (2010). Diverticulosis, diverticulitis, and appendicitis. In EG Nabel, ed., ACP Medicine, section 4, chap. 12. Hamilton, ON: BC Decker.
Davis BR, Matthews JB (2006). Diverticular disease of the colon. In M Wolfe et al., eds., Therapy of Digestive Disorders, 2nd ed., pp. 855–859. Philadelphia: Saunders Elsevier.
To learn more visit Healthwise.org
© 1995-2013 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.