Diverticulitis is a complication that can affect people with diverticulosis, small pockets on the inside of their colon. If one of the pockets becomes injured or infected, it can cause inflammation inside. If you have a sharp pain in your lower left abdominal quadrant, it might be diverticulitis.
Diverticulitis is inflammation in your diverticula, which are small pockets that can develop on the inside of your colon. Having diverticula is called diverticulosis. It’s common as you get older, and most people never have any problems with it. But if one of your diverticula becomes inflamed, it can cause acute pain and other symptoms. It might mean that it has an infection, which needs medical attention.
Although diverticulosis is common, diverticulitis is an uncommon complication. It affects about 4% of people with diverticulosis. Once you’ve had it, you have a 20% chance of getting it again.
Healthcare providers classify diverticulitis as acute or chronic and as complicated or uncomplicated.
Diverticulitis begins as an acute problem, which means that it comes on suddenly and goes away shortly with treatment. But some people have recurring (repeat) episodes of diverticulitis, and some people develop chronic inflammation. There are different theories about why this happens. It may be because an acute episode didn’t heal completely, or it may be related to another chronic condition in your colon.
Most of the time, diverticulitis is uncomplicated, which means that inflammation and possible infection are the extents of the problem. It heals easily with the right treatment. Diverticulitis becomes complicated when the inflammation begins to cause secondary problems. For example, severe acute inflammation may cause a diverticulum (singular of diverticula) to rupture. Chronic inflammation may cause scarring.
Symptoms may include:
Whether you’re having an acute diverticulitis attack or a flare-up of chronic diverticulitis, the pain will be similar. An acute attack may come on more suddenly, while a chronic flare-up may build up over a few days. You should be able to locate it in the precise spot where your diverticulum has become inflamed. It may feel sharp and penetrating or have a burning quality. The pain is usually moderate to severe.
In people of European descent, diverticula most often occur in the last part of the colon, called the sigmoid colon. This segment begins on your lower left side and tilts slightly to the right to meet your rectum. For this reason, most people feel diverticulitis pain in the lower left quadrant of their abdomen. Occasionally, lower abdominal pain may also spread to your pelvis or radiate to your back.
However, in people of Asian descent, it’s more common to have diverticulosis in the first part of the colon, which is in your upper right quadrant. Diverticulitis here might cause upper abdominal pain.
Inflammation in your diverticula often involves a tear in the lining and infection, though it’s not always clear which came first. On one hand, diverticula make great hiding places for bacteria to set up camp and multiply. This might happen if, for example, some poop gets stuck in one of them. A bacterial infection might trigger inflammation, and inflammation might cause a diverticulum to swell and tear.
On the other hand, if a diverticulum tears for another reason, it can easily become infected by normal levels of bacteria living in your colon. It might tear if hard poop stretches it while passing through, or if it’s been affected by general colitis (inflammation in your colon). Some studies have suggested that cytomegalovirus (CMV) infection in your colon might be a significant factor in triggering diverticulitis.
Diverticulitis seems to occur incidentally (by chance). But genetics might be partly involved in getting diverticulosis. Although you aren’t born with diverticulosis, you’re more likely to develop it in a certain part of your colon if you’re of European or Asian descent. It’s also possible that genetics could influence your likelihood of developing chronic inflammation. More research is needed on this subject.
Diverticulitis is uncomplicated 80% of the time. But severe or persistent diverticulitis can lead to complications such as:
You might’ve developed complications if you notice:
If you and your healthcare provider already know that you have diverticulosis, they might recognize your symptoms as possible diverticulitis. But people often don’t know, and the symptoms of diverticulitis can resemble many other conditions. Your healthcare provider may begin with some routine tests to rule out other causes, such as a blood test (comprehensive metabolic panel), stool test or urine test.
When your provider suspects diverticulitis, they’ll look for it on imaging tests. A CT scan works well: it’s quick and can show the extent of the inflammation as well as any related complications. In some cases, your provider might need to look inside your colon with a lighted scope to investigate further. This is called a colonoscopy. They might be able to treat some complications during the colonoscopy.
If it’s mild and uncomplicated, it can go away on its own. But you should still go to a healthcare provider to have it evaluated. They might need to give you antibiotics for an infection, and some people might need prescription pain medications. Your provider will also tell you how to care for yourself at home while you’re recovering. It takes about a week. They’ll want you to keep in touch during this time.
If your healthcare provider has given you the go-ahead, you can treat diverticulitis at home with:
Healthcare providers suggest that you avoid NSAIDs when you have diverticulitis, as they can increase your risk of bleeding. NSAID stands for “nonsteroidal anti-inflammatory drugs.” These include:
You may not need treatment if you have a mild and uncomplicated case. But it’s important to see a healthcare provider about diverticulitis. If you don’t, you may end up with a more severe and complicated case. Certain infections may need to be treated with antibiotics or antivirals to go away. Inflammation that doesn’t go away may begin to cause secondary problems. Pain may also worsen.
If conservative at-home treatment hasn’t worked, or if you have severe, chronic or complicated diverticulitis, you may need to stay in the hospital for treatment. Treatment may include:
Healthcare providers don’t know enough about why diverticulitis happens or why it returns to know definitively how to prevent it. But they suspect that general bowel wellness can help. Eating more plants and fewer animal fats, drinking enough water and getting some regular exercise can help keep your bowel movements healthy. For some people, they might recommend fiber supplements or probiotics.
In the past, people with diverticulosis were told to avoid seeds and nuts, in case one might get stuck in a diverticulum and cause diverticulitis. This risk is considered mostly a myth today. Seeds and nuts are great sources of fiber and plant-based protein, and they tend to appear in healthy meals. It’s much better for your bowels to maintain a healthy diet overall than to worry about the rare chance of a seed going awry.
Only a small percentage of people will have complicated diverticulitis, and only a small percentage of those will need surgery. In most cases, even complicated diverticulitis resolves quickly and completely with treatment. Diverticulitis shouldn’t affect your overall life expectancy. Only in the unlikely event of a bowel perforation or a ruptured abscess would you be at risk of life-threatening complications.
If diet and lifestyle improvements haven’t prevented diverticulitis from recurring, there might be other factors involved that put you more at risk. People with weakened immune systems are more prone to frequent infections and slower to recover. People with autoimmune diseases are more likely to have chronic inflammation. Even the balance of different bacteria living in your gut may affect your gut immunity.
Healthcare providers don’t always know why diverticulitis continues to return in some people. But if it’s returned more than once, and if it’s brought complications at least once, they might suggest an elective bowel resection to resolve it. That means removing the small section of your colon that’s causing the trouble. If it’s not an emergency, you can probably do this as a one-step surgery without a colostomy.
A note from Cleveland Clinic
Diverticulitis is an uncommon complication of diverticulosis. Diverticulitis that causes its own complications is even less common. But if it happens to you, you might need urgent care. See a healthcare provider right away for symptoms of diverticulitis. They’ll figure out what kind of treatment you need and whether you can treat it safely at home, or if you need to stay in the hospital for treatment.
Last reviewed by a Cleveland Clinic medical professional on 04/10/2023.
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