Understanding Diverticulitis vs. Appendicitis

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Sharp and sudden lower abdominal pain is a common reason for urgent care. The problem can be a symptom of many problems, including diverticulitis and appendicitis.

While both problems are caused by inflammation, they affect these two distinct areas:

  • Appendicitis occurs as a result of an inflamed appendix.
  • Diverticulitis results from inflamed diverticula, small bulging pockets that can form in the colon wall as we age.

This article discusses diverticulitis vs. appendicitis, including symptoms, testing, and recovery.

stomach pain

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Right-Sided Pain From Diverticulitis vs. Appendicitis

Diverticulitis and appendicitis can both cause pain in your abdomen's right side.

Right-sided diverticulitis pain can be confused with the right-sided pain common in appendicitis.

While both conditions affect the colon, the causes and impact of diverticulitis vs. appendicitis are diverse.

Colon Anatomy

Your colon—also called the large intestine—is part of your digestive system. The colon removes water and some nutrients from the food and other substances left after processing in the small intestine. The colon forms the remaining material into stool and passes it to the rectum for removal through the anus.

The colon starts from an enlarged area at the end of the small intestine, called the cecum, and ends at the anus. The appendix is a small, fingerlike tube of intestinal tissue extending from the cecum on the lower right side of your abdomen.

After the cecum, the colon consists of the following five sections:

  • Ascending colon, or right colon (the first section of the colon)
  • Transverse colon (crosses the abdomen)
  • Descending colon (follows down the left abdomen toward the end of the colon)
  • Sigmoid colon (S-shaped, short curving of the colon at the end of the colon)
  • Rectum (last part of the digestive tract before the anus)

Causes Associated With Inflammation

Inflammation occurs when your body responds to a threat. The following causes can trigger this reaction in the intestine:

  • Enlarged tissue caused by infection by a virus, bacterium, or parasite
  • Tissue perforation
  • Hardened stool or growths that cause a blockage
  • Inflammatory bowel disease (inflammation of the lining of the digestive tract that leads to Crohn's disease or ulcerative colitis)
  • Intestinal tumor
  • Injury or trauma

Meckel's Diverticulum

Meckel's diverticulum is the most common congenital (present at birth) anomaly of the digestive system, affecting up to 4% of the population. The condition causes a small pouch to form in the wall of the intestine, near the point where the small and large intestines meet.

Symptoms do not always occur, or they may come and go. Problems can include abdominal pain, cramping, bleeding in the digestive tract, or diverticulitis, usually during childhood.

Pain Location

Pain location can differ between diverticulitis and appendicitis, as follows:

  • Diverticulitis: Usually starts on the lower left side of the abdomen, where the pockets commonly develop within the colon. Diverticulitis pain can also occur on the right side or near the public bone. Pain may radiate to the leg, back, groin, or side.
  • Appendicitis: Usually occurs in the abdomen. It starts around your mid to upper abdomen and then moves to the lower right. About 12 to 24 hours after symptoms begin, the pain usually settles at McBurney's point, an area in the abdomen just above the appendix. This area becomes tender to the touch during appendicitis. If the pain spreads, it may affect your entire abdomen.

Cecal Diverticulitis

Cecal diverticulitis is a rare type of diverticulitis that presents clinically similar to acute appendicitis.

Symptoms include intense tenderness and pain in the lower right side. Research shows that more than two-thirds of people with cecal diverticulitis undergo surgery with a presumptive diagnosis of acute appendicitis.

Pain Sensation

Pain sensation can differ between diverticulitis and appendicitis, as follows:

  • Diverticulitis often begins suddenly and severely. It can also occur as a mild ache that worsens over several days.
  • Appendicitis tends to start mild and progress to more severe pain over several hours. It can also come on suddenly, being so severe that it awakens you from sleep. Coughing, sneezing, moving, or breathing deeply may worsen the pain. Appendicitis pain may feel unlike any other abdominal pain you've had.

When to Seek Immediate Medical Attention

Abdominal pain on either side of your body may signify diverticulitis, appendicitis, or many other serious conditions. These issues can progress to severe and possibly life-threatening without proper care.

Seek immediate care if you have sudden and severe abdominal pain accompanied by any of the following symptoms:


Symptoms of diverticulitis and appendicitis depend on the extent of your condition and whether complications exist. Both conditions affect your colon and the areas surrounding it. Infections can spread and impact other parts of your body, leading to many problems that can quickly become serious.


Symptoms of diverticulitis occur when one of the individual diverticula becomes perforated, causing an inflammation. Symptoms can include the following:

Risk Factors for Diverticulitis

Several modifiable and unmodifiable factors can increase your risk of diverticulitis. The following characteristics can make you more susceptible to this condition:


Symptoms of appendicitis can start mild and then get very severe quickly. Pain may also disappear for a period, then return. These symptoms typically include the following:

  • Abdominal swelling
  • Constipation
  • Diarrhea
  • Loss of appetite
  • Nausea
  • Vomiting

Risk Factors for Appendicitis

Appendicitis can affect anyone at any age. However, people in the following categories have a higher risk of getting appendicitis:

  • Teens and young adults less than age 30
  • Anyone with a family history of appendicitis, especially males
  • Children with cystic fibrosis

Diagnostic Testing

Many of the symptoms of diverticulitis and appendicitis are not unique to these conditions, which can complicate getting a diagnosis. However, delaying a diagnosis or misdiagnosing diverticulitis or appendicitis can increase your risk of an infection spreading and posing serious problems.

Diagnosing the cause of abdominal pain can include the following:


The following diagnostic tests can help your healthcare provider confirm diverticulitis.

  • Abdominal computed tomography (CT) scan: The CT scan is the most precise tool to diagnose diverticular disease. It provides cross-sectional, two- and three-dimensional images of the gastrointestinal tract, including inflamed or infected diverticula and the severity of the condition. A CT scan can also identify other abnormalities in the colon and the surrounding area.
  • Colonoscopy: A colonoscopy allows your physician to view the interior of the entire length of the large intestine. It can help identify colon cancer and sources of abdominal pain, rectal bleeding, or changes in bowel habits.


Imaging techniques can help avoid a delay in diagnosis, possible perforation of the appendix, and unnecessary appendectomy of a healthy appendix. Misdiagnosis can occur when findings are inconclusive. This can occur because the appendix is small and hard to locate.

The following diagnostic techniques are most often used when appendicitis is suspected:

  • CT scan: Studies show that the CT scan is highly sensitive and specific in diagnosing acute appendicitis and alternative causes of abdominal pain. Concerns regarding radiation exposure, risk of contrast administration, and high cost may affect the decision to choose an alternative method to evaluate for appendicitis, especially for children and pregnant women.
  • Abdominal ultrasound: An abdominal ultrasound can be reliable in identifying an abnormal appendix though it may not provide the same accuracy in identifying a normal appendix to rule out appendicitis. As an alternative to a CT scan in diagnosing appendicitis, ultrasound is easy, inexpensive, fast, and easily portable.
  • Magnetic resonance imaging (MRI): Magnetic resonance imaging (MRI) has a high degree of efficiency in diagnosing appendicitis, though it is not commonly used as a first-line diagnostic tool for appendicitis.

Appendicitis Recovery

Recovery from appendicitis varies based on the type of treatment received.

The gold standard for appendicitis treatment is an appendectomy, which is the surgical removal of the appendix. The procedure can be performed using open surgery or less-invasive laparoscopic techniques.

Recovery from open surgery can take from two to four weeks. Since laparoscopic surgery uses smaller incisions, this technique usually has a faster recovery and fewer complications than open surgery. People who undergo an appendectomy via laparoscopic surgery can usually return to work and normal routines within one to three weeks after surgery.

Appendicitis recovery involves avoiding lifting heavy objects and strenuous activities like aerobic exercise or weight lifting until your healthcare provider advises that you are ready to do so.

The rate of recurrence after an appendectomy is virtually nonexistent. In rare circumstances, an infection can develop on the remnant portion of the appendix, called the appendiceal stump,

Antibiotics for Acute Appendicitis

People with acute appendicitis without complications may be eligible to treat their condition without surgery. Results from the Comparison of Outcomes of Antibiotic Drugs and Appendectomy (CODA), a large, randomized study of 25 U.S. centers, reported that treatment with antibiotics was comparable to an appendectomy in the short term.

The antibiotic treatment typically involves receiving intravenous (IV) antibiotics in the hospital for 24 to 72 hours. Upon discharge, patients must continue taking oral antibiotics for seven days at home. Recuperation is faster with antibiotics, with fewer lost workdays and a faster return to normal activities.

However, treating appendicitis with antibiotics does not give you the peace of mind that comes with removing the diseased organ. This therapy leaves you vulnerable to recurrence. The CODA study showed that 30% of participants treated with antibiotics had undergone an appendectomy within 90 days of treatment.

Is Surgery Better?

Research indicates that treating uncomplicated appendicitis with antibiotics delivers results similar to an appendectomy. Whether surgery or antibiotics are better depends on many factors, including age, other medical conditions, and personal preference.

While recovery can take up to a month, surgery gives you peace of mind knowing that the problem is permanently solved. However, antibiotics may be a more favorable option if you are elderly, have a complex medical condition, or have another situation that makes surgery a higher-than-normal risk.

In some cases, there is no choice. Surgery is the only option for treating complicated appendicitis that involves the risk of life-threatening sepsis because of infection from a perforated appendix or abscess.

Diverticulitis Treatment

The type of diverticulitis treatment you receive depends on whether your problem is defined as simple or complicated. Short-term problems are also handled differently from those that occur repeatedly or last a long time.


Simple diverticulitis is treated with antibiotics, though medication is not always necessary. If antibiotics are needed, treatment may be administered at home without hospitalization. A clear liquid diet may be advised to give your colon time to heal.

Without treatment, diverticulitis can become severe and progress to complicated diverticulitis. Diverticulitis is categorized as complicated when one of the following characteristics exists:

  • Abscess, or collection of pus, outside your colon wall
  • Phlegmon, an infection that spreads between muscle fibers and along tissue planes
  • Generalized infection in the lining of the abdominal cavity called peritonitis
  • Perforation, or hole, in the infected diverticula
  • Fistula (an abnormal connection between the large intestine and another organ)
  • Stricture (narrowing of the colon that prevents stool from passing)
  • Bleeding from a diverticular sac
  • Bowel obstruction caused by too much scar tissue

Treatment of complicated diverticulitis typically involves the following steps:

  • Hospitalization with IV antibiotics followed by oral antibiotics after discharge
  • Percutaneous CT guided drainage of abscess over 2 inches (5 centimeters)
  • Potential angiography or colonoscopy to stop bleeding

When diverticulitis causes severe damage or a potentially life-threatening condition like peritonitis or colonic perforation, diverticulitis surgery may be advised. Depending on your condition, surgery may be performed with either traditional open surgery or laparoscopic techniques. It involves one of the following procedures:

  • Partial colon resection with anastomosis: The damaged portion of the colon is removed, and the cut ends are joined so you can eliminate waste normally.
  • Partial colon resection with colostomy: The damaged portion of the colon is removed and the healthy end of the colon is connected to a stoma, a hole in the abdomen. Waste empties into an ostomy bag, an external pouch attached to the stoma.


Chronic diverticulitis describes diverticulitis that occurs with one of the following characteristics:

  • Repeated attacks of diverticulitis
  • One long course of a single diverticulitis attack
  • Stricture and fistula caused by repeated attacks

Treatment of chronic diverticulitis usually involves surgery to remove the inflamed parts of the colon. It can also involve correcting complications, such as stricture or fistula, that occurred due to an acute attack and remain problematic.


There are many causes of stomach pain. Symptoms of diverticulitis and appendicitis can be confused because they can cause pain on one side of the body. Both problems occur when inflammation strikes an area of the colon, or large intestine, in response to damage or disease.

Germs, stool, or a tumor can cause an inflamed appendix. When this occurs, your body reacts with inflammation to protect itself from the problem. Diverticulitis results when diverticula, small bulging pockets that form in the colon, become inflamed. Both issues can be acute or chronic problems that can become severe without treatment.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Anna Giorgi
Anna Zernone Giorgi is a writer who specializes in health and lifestyle topics. Her experience includes over 25 years of writing on health and wellness-related subjects for consumers and medical professionals, in addition to holding positions in healthcare communications.