What Is Diverticulitis? Symptoms, Causes, Diagnosis, Treatment, and Prevention
Diverticulitis is an infectious inflammatory condition that occurs when small pouches, called diverticula, develop in the inner layers of the colon and protrude out through weak spots in the colon’s muscular outer layer.
The development of these diverticula pouches is known as diverticulosis, which on its own may not cause any issues. But diverticulitis happens when the diverticula become inflamed, and it can lead to serious complications if not treated.
While diverticulosis doesn’t always present symptoms, there are clear warning signs of diverticulitis, the inflamed form of the condition, including:
Although many of these symptoms overlap with other gastrointestinal problems, including peptic ulcers and irritable bowel syndrome (IBS), consult your doctor if you have any of these symptoms and the risk factors of diverticulitis apply to you.
What Does Diverticulitis Pain Feel Like?
During the digestive process, the colon (also called the large intestine or large bowel) is responsible for absorbing liquid from food and breaking down any remaining material to move it to the rectum. The rectum acts as a storage space for this waste, and its muscles help your body remove stool through the anus.
The sigmoid colon is the S-shaped lower section of your colon, which links the descending colon to your rectum. In Western countries, most diverticula develop in the sigmoid colon (the lower left part of your abdomen).
When diverticulosis becomes inflamed and progresses to diverticulitis, you may feel persistent pain in the area of the sigmoid colon and potentially develop fever and chills.
The pain can come on suddenly and severely, or it may increase in severity over a period of days. It can also fluctuate in intensity.
Ultimately, the degree of pain you experience from a flare-up of diverticulitis depends on its severity and whether it is localized, caused by an abscess (pus pocket), or has spread throughout the abdomen.
Advanced Symptoms of Diverticulitis
If you experience any of these advanced symptoms, a diverticulitis complication may have developed:
Fever over 100 degrees F (38 degrees C)
Worsening or severe abdominal pain
Inability to tolerate fluids
Feeling light-headed, dizzy, or showing other signs of low blood pressure.
If you have any of these symptoms, get in touch with your doctor as soon as possible.
Diverticula form when the inner soft-tissue layer of the intestine passes through the outer muscular layer, forming a pocket or pouch-like, marble-size bulge. This happens most often where the muscles of the intestine are weakest, particularly in the sigmoid colon.
It’s unclear why diverticula form, but they’re linked with these factors:
Aging People older than 40 are more likely to be diagnosed with diverticulitis.
Smoking People who smoke cigarettes are more likely to get diverticulitis.
Inactivity Vigorous exercise appears to ward off diverticulitis. Regularly aim for 150 minutes of moderate-intensity aerobicexercise (such as brisk walking) each week.
Certain Medications Steroids, opioids, and nonsteroidal anti-inflammatory drugs (NSAIDs) increase the risk of diverticulitis.
Can Nuts and Seeds Increase Your Risk of Diverticulitis?
This theory explains why, for decades, doctors advised people with diverticulosis (the presence of diverticula) not to eat nuts, seeds, or popcorn, which they believed could block the openings of the diverticula and lead to flare-ups of diverticulitis.
But research has never proved that these foods lead to diverticulitis, so doctors no longer warn their patients away from such foods.
Can a Low-Fiber Diet Cause Diverticula to Form?
Research suggests that the link between a low-fiber diet and an increased risk of diverticulitis is simply that — a link without a causal relationship, at least for now.
Scientists long believed that lack of fiber could increase the risk of diverticulosis, but research suggests that’s not necessarily the case.
If you are experiencing any of the symptoms of diverticulitis, your doctor will likely take the following actions:
Gather information about your full medical history, including preexisting conditions and risk factors
Examine your abdomen to check for tenderness
Perform a rectal exam to check for rectal bleeding
Perform a blood test to check your white blood cells and determine if you have active inflammation
Order a diagnostic test to get a picture of your colon and determine if diverticula are present and whether they are inflamed or infected
The most common test used to diagnose diverticulitis is a CT scan. A CT scan uses both X-rays and computer technology to create three-dimensional images of your colon.
Prognosis of Diverticulitis
While some people with diverticulitis will require intravenous antibiotics or even surgery, many can be treated at home.
If you experience increasing pain, fever, or an inability to tolerate fluids, you may need to be hospitalized, as these symptoms may indicate severe diverticulitis.
Your doctor may recommend hospitalization if you have the following characteristics or symptoms:
You are older.
You are unable to take oral fluids.
You have other existing health conditions.
The inflammation or infection you are experiencing is particularly severe.
With home treatments, symptoms of diverticulitis usually clear up within 7 to 10 days. Your doctor will likely schedule several follow-up visits to assess your condition.
If you are generally in good health and the inflammation or infection you are experiencing is not severe, your doctor will likely proceed with nonsurgical, at-home treatments for diverticulitis.
Diet Options
For mild cases, doctors prescribe a light or low-residue diet. Sometimes a clear liquid diet for a few days is required to treat diverticulitis. This allows your digestive tract to rest and begin healing and will also keep you hydrated.
Foods and drinks to consume might include:
Clear broths
Clear soups
Juices without pulp, such as apple juice
Plain gelatin
Ice chips
Water
Tea without milk
As you begin to feel better, you can start reintroducing foods into your diet, including:
Canned or cooked fruit and vegetables with no skin or seeds
Eggs, fish, and poultry
White bread
Low-fiber cereal
Milk, yogurt, and cheese
White rice, pasta, and noodles
Medication Options
In the past, oral antibiotics were considered the first line of therapy for uncomplicated diverticulitis. Recent guidance from the American College of Physicians states that low-risk cases can be treated without antibiotics.
For most patients, bowel rest and a liquid diet should be enough to manage uncomplicated diverticulitis.
The guidance states that doctors may prescribe antibiotics for some patients, including those who are immunocompromised or medically frail.
These broad-spectrum antibiotics are commonly used:
metronidazole (Flagyl)
sulfamethoxazole and trimethoprim (Bactrim)
ciprofloxacin (Cipro)
amoxicillin and clavulanate (Augmentin)
OTC pain relievers used to treat diverticulitis include acetaminophen (Tylenol). Narcotics are not recommended because they can increase pressure in the colon.
Surgery Options
If you have two or more repeated episodes of diverticulitis, you may need surgery.
In more complicated cases of diverticulitis — an abscess or gross peritonitis (a leakage or hole in the intestines) you may need surgery to remove the diseased part of your colon. Primary bowel resection, which reconnects the healthy sections of your colon after removing the diseased part, is one option. A bowel resection with colostomy is another option.
Alternative and Complementary Therapies
There is very little evidence that alternative therapies and complementary supplements are useful treatments for diverticulitis. Glutamine (an amino acid that aids in digestion), fish oil (high in omega-3 fatty acids), flaxseed, and probiotics (which help maintain intestinal health) have all been studied as treatment options, but the results have been inconclusive.
It’s also recommended to eat a diet high in fiber. Fiber-rich foods like whole grains, fruits, and vegetables soften stool and help it pass more easily.
Left untreated, diverticulitis can lead to life-threatening complications.
About 25 percent of people with diverticulitis develop complications. Some of these include:
Abscess
Fistula
Peritonitis
Rectal bleeding
Intestinal obstruction
As with many diseases, age is a risk factor for diverticulitis complications, but simply having one attack can put you at about a 50 percent risk of having a second in 5 to 10 years.
You can help prevent diverticulitis complications by maintaining a healthy weight, eating enough fiber, not smoking, exercising regularly, and visiting the doctor on a regular basis.
Even though diverticulosis is harmless and usually doesn’t cause any symptoms, some research suggests people with this condition have a 10 to 25 percent lifetime risk of developing diverticulitis.
Other research, however, finds that less than 5 percent of people with diverticulosis go on to develop diverticulitis.
In the United States, an estimated 30 percent of people between ages 50 and 59 have diverticulosis, and that number rises to more than 70 percent for people over age 80.
Each year, about 200,000 people are hospitalized for diverticulitis and about 70,000 people are hospitalized for diverticular bleeding.
Diverticulitis affects people differently, with complications and hospitalization occurring more commonly among certain races and ethnic groups — namely Black, Hispanic, and Native Americans.
Black Americans and Diverticulitis
According to research, there were about 30 hospitalizations for diverticulitis per 100,000 Black Americans between 2000 and 2010. Diverticular bleeding was more prevalent in Black people during this 10-year period, too. This may be related to hypertension and diabetes (both risk factors for diverticular hemorrhage), which are more common in Black Americans.
But bleeding isn’t the only concern — surgery is another. Research examining the charts of 327 people with diverticulitis found that Black participants were “more likely than any other racial group to require surgery for recurrent diverticulitis after at least one medically managed hospital admission for the condition.”
Hispanic Americans and Diverticulitis
The rate of hospitalization among Hispanic Americans with diverticulitis is similar to that of Black Americans, about 32 per 100,000 cases. Hispanic Americans are less likely to have surgery for recurrent diverticulitis, however, and they’re also less likely to have diverticular bleeding, according to research.
Native Americans and Diverticulitis
Native Americans are a smaller population, but research finds the highest prevalence of diverticulitis among this group.
It’s believed that this disparity is largely due to the higher rate of diverticulitis risk factors like smoking, obesity, and physical inactivity among Native Americans.
When left untreated, diverticulitis can cause complications such as a bowel obstruction, perforation, or abscess.
But conditions related to diverticulitis aren’t limited to those affecting the gastrointestinal tract. Diverticulitis has been associated with other ailments, too.
Colorectal Cancer
After hospitalization for diverticular disease, a person’s risk of colorectal cancer, which affects the colon and rectum, may be elevated, according to a research paper. Indeed, the risk of this type of cancer is 40-fold higher in people with acute diverticulitis than in the general population. In general, a colonoscopy is recommended in the United States after a diverticulitis episode to identify potential colorectal cancer.
Heart Disease
One study evaluating the risk of acute coronary syndrome (ACS) in people with and without diverticular disease found that ACS was significantly higher in the group living with diverticular disease. The exact link is unknown, but chronic inflammation likely contributes to both conditions, and they have similar risk factors (obesity, inactivity, smoking, and hypertension).
Type 2 Diabetes
Type 2 diabetes, which weakens the immune system and increases the risk of infections, is another disease that can occur alongside, and may even increase the severity of, diverticulitis.
Dementia
Those with dementia are at a higher risk of developing diverticular disease, but the exact relationship between the two conditions remains unclear.
The Takeaway
Diverticulitis is an inflammatory condition in which small pouches (diverticula) form in the small intestine and become infected or inflamed. Common symptoms include abdominal pain, changes in bowel habits, fever and chills, and nausea and vomiting. The exact causes are not known, however, the risk factors seem to include aging, obesity, a lack of exercise, and some medications such as NSAIDs. Research suggests that there is a link between diverticulitis and a low-fiber diet. Treatment options include a liquid diet, pain medications, and antibiotics. In severe cases, surgery may be needed to remove affected areas of the colon. A doctor or healthcare provider can advise you on the best course of action.
