What Is Appendicitis? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Medically Reviewed

Appendicitis is a painful medical condition in which theappendixbecomes inflamed and filled with pus, a fluid made up of dead cells and inflammatory tissue that often results from an infection.

Appendicitis is one of the leading causes of sudden severeabdominal painrequiring surgery in the United States, according to the National Institutes of Health (NIH). (1)

The appendix is a small, finger-shaped pouch attached to the large intestine on the lower right side of the abdomen.

The Role of the Appendix, and Living Without It

It's not entirely clear what role the appendix plays in the body. It’s long been thought to be a vestigial organ that doesn’t have much of a useful role, but newer research suggests that it may have some immune function, helping our system rebalance itself aftergastrointestinal diseaseoccurs. (2)

A particular type of tissue associated with the infection-fighting lymphatic system is found in the appendix. This tissue encourages certain beneficialgut bacteriato grow, aiding in digestion and immunity. Research has revealed that the lining of the gut has a biofilm — a thin layer of microbes,mucus, and immune system molecules — and this biofilm appears to be most pronounced in the appendix. (3) Some experts theorize that when certain diseases wipe outbeneficial gut bacteriain the GI tract, the bacteria emerge from the appendix biofilm and recolonize the gut. (2)

Still, removing the appendix doesn’t appear to cause any harm or negative health consequences. People can live perfectly normal lives without their appendix. In some cases, removal of an inflamed appendix appears to have a protective effect:Researchhas shown that young people who underwent an appendectomy for appendicitis had a lower risk for developingulcerative colitis.(4)

Learn More About the Appendix

What Happens When the Appendix Ruptures

Inflammation of this abdominal organ can be a serious, life-threatening condition. If not treated promptly, appendicitis may cause the appendix to burst (aruptured appendix), spreading an infection throughout the abdomen. The appendix can burst in as little as 48 to 72 hours after symptoms begin.(5)

When people mention appendicitis, they're typically referring to acute appendicitis, which is marked by severe abdominal pain that quickly spreads and worsens over a matter of hours.

In some cases, however, people may developchronic appendicitis, which causes mild, recurrent abdominal pain that often subsides on its own. These patients usually don't realize they have appendicitis until an acute episode strikes.

Learn More About a Ruptured Appendix

Signs and Symptoms of Appendicitis

Early warning signs of appendicitis include an aching pain that begins around the belly button and then slowly localizes over the lower right abdomen.

Appendicitis pain sharpens over several hours and can worsen when you move, take a deep breath,cough, and sneeze. Other symptoms of appendicitis may follow, including:

  • Nausea
  • Vomiting
  • Constipationor diarrhea
  • Inability to pass gas
  • Loss of appetite
  • Abdominal swelling
  • Low-grade fever
  • The feeling that having abowel movementwill relieve discomfort

The typical symptoms of appendicitis don’t always occur, and sometimes people don’t show the telltale signs. This is more often the case in children and pregnant women. Appendicitis also shares many symptoms with other sources of abdominal pain, which can make it challenging to definitively diagnose.(6)

Learn More About the Symptoms of Appendicitis

Causes and Risk Factors of Appendicitis

It's not always clearwhat causes appendicitis, and while there seems to be some correlation with a family history, there’s no way to know if or when you might get appendicitis. (7,8) The condition often arises from one of two issues: A gastrointestinal infection (viral, bacterial, or fungal) that has spread to the appendix (9) or an obstruction that blocks the opening of the appendix. (10)

In the second case, there can be several different sources of blockage. These include:

  • Lymph tissue in the wall of the appendix that has become enlarged
  • Hardened stool, parasites, or other growths
  • Irritation andulcersin the gastrointestinal tract
  • Abdominal injury or trauma
  • Foreign objects, such as pins, stones, or bullets

Air pollution has also been linked to an increased risk for appendicitis. Scientists suspect that high levels of ozone might increase inflammation in the intestine or increase susceptibility to infection. (11)

When a person's appendix becomes infected or obstructed, bacteria inside the organ multiply rapidly. This bacterial takeover causes the appendix to become infected and swollen with pus.

Learn More About the Causes of Appendicitis

How Is Appendicitis Diagnosed?

There isn’t one specific test to diagnose appendicitis. After learning about a patient's medical history and recent pattern of symptoms, doctors will use a number of tests to gather the information they need to diagnose appendicitis. (10) Your healthcare team may:

Learn More About Abdominal Pain

Appendicitis in Children Can Be Difficult to Diagnose

Approximately 80,000 children get appendicitis each year. Appendicitis is one of the most common reasons kids need emergency abdominal surgery. Up to 30 percent of kids with appendicitis, especially those under age 5 who have difficulty describing their symptoms, will have a perforated (ruptured) appendix. (14)

Symptoms such as nausea, vomiting, and lack of appetite, which can all occur with appendicitis, aren’t necessarily predictive ofappendicitis in children, according to a study published in theJournal of the American Medical Association.(15)

Signs of appendicitis can also look different in very young children. Kids between ages 2 and 5 most often experience stomachaches and vomiting if they have appendicitis. Fever and loss of appetite also frequently occur, while in infants younger than 2, appendicitis usually causes a bloated or swollen stomach.(16)

To confirm a diagnosis of appendicitis in children, doctors use imaging procedures. To lessen radiation exposure in children, the ACR recommends performing an ultrasound first, followed by acomputed tomography(CT) scan only if the ultrasound is inconclusive. (17)

Learn More About Appendicitis in Children

Duration of Appendicitis

Appendicitis pain and other symptoms tend to show up quickly, usually within 24 hours. Signs of appendicitis can appear anywhere between 4 and 48 hours of an infection.

Anyone who suspects appendicitis in themselves or their child should go to the emergency room right away to prevent complications. The earlier appendicitis is treated, the better. (14)

Though rare, the symptoms caused by inflammation of the appendix can sometimes last a long time — chronic appendicitis. In these cases, pain in the lower right abdomen can last for weeks, months, or even years. (19)

Treatment and Medication Options for Appendicitis

In some cases, doctors will treatappendicitis with antibiotics, but the infection needs to be mild and uncomplicated (meaning the appendix hasn’t perforated and the infection hasn’t spread).

Appendicitis is usually considered a medical emergency, and doctors treat the condition with an appendectomy, the surgical removal of the appendix.

Surgeons will remove the appendix using one of two methods: open orlaparoscopic surgery.

Anopen appendectomy(laparotomy) requires a single incision in the appendix region, the lower right area of the abdomen.

During laparoscopic surgery, on the other hand, surgeons insert special surgical tools into several smaller incisions. This option is believed to have fewer complications and a shorter recovery time. (12)

If a person's appendix isn't treated in time, it may burst and spread the infection throughout the abdomen, leading to a life-threatening condition calledperitonitis, an inflammation and infection of the peritoneum(the lining of the abdominal cavity).Symptoms of peritonitisinclude fever, nausea, vomiting,bloating, and severe tenderness in the abdomen. (1) Peritonitis is usually treated with antibiotics, and surgery is often necessary to remove the infected tissue and prevent the infection from spreading. (20)

In other cases of complicated appendicitis, abscesses may form on or around the burst appendix. In both these cases, surgeons will usually drain the abdomen or abscess of pus and treat the infection with antibiotics before removing the appendix.

之前和之后使用抗生素an appendectomy to prevent wound infections.

Doctors might do what’s known as an “interval appendectomy” if a patient has a ruptured appendix: antibiotics are administered first, and once they successfully clear the infection, an appendectomy is performed several weeks later. (12)

Because there’s no perfect test to confirm appendicitis, and other illnesses can cause symptoms similar to those of appendicitis, your doctor might find during appendectomy surgery that the appendix is not actually infected. According to the NIH, this can happen up to 25 percent of the time. If this occurs, your surgeon will often still remove the appendix as a prophylactic measure. (10)

Learn More About Appendectomy

Chronic vs. Acute Appendicitis

Acute appendicitis happens quickly and needs to be treated urgently. But in some cases, the symptoms caused by inflammation of the appendix — especially pain in the lower right abdomen — can last for weeks, months, or even years, subsiding on their own and then later recurring. This is called chronic appendicitis, and it accounts for approximately 1.5 percent of all appendicitis cases. (10)

Chronic appendicitis may be misdiagnosed because the symptoms can mimic those of other conditions, such asCrohn’s diseaseorpelvic inflammatory disease. Once chronic appendicitis is properly diagnosed, an appendectomy resolves symptoms for most patients.(21)

Learn More About Chronic Appendicitis

Antibiotics as a Treatment for Appendicitis

在过去的几年里,研究表明uncomplicated appendicitis — appendicitis without a ruptured appendix, pus-filled abscesses, or peritonitis — can be treated with antibiotics alone. This approach has advantages: Patients whose appendicitis is treated with antibiotics instead of an appendectomy require less pain medication and have fewer complications. It’s also less expensive.(22)

Still, whether antibiotics-only should become the first-line treatment for cases of uncomplicated appendicitis is up for discussion. It can be hard to distinguish complicated appendicitis from uncomplicated; sometimes the complexity can’t be determined until the operation. And there’s a higher chance of recurrence with antibiotics-only treatment: In a study published in 2015 in JAMA,among patients with uncomplicated appendicitis treated only with antibiotics, 27 percent required surgical intervention within a year.(23)

Areview of studies published in October 2017 inWorld Journal of Emergency Surgeryconcluded that while nonoperativeantibiotictreatment is an effective alternative, appendectomy remains the “gold standard of treatment” for uncomplicated appendicitis.(24)

Learn More About Antibiotics and Appendicitis

Prevention of Appendicitis

There is no known way to prevent appendicitis. For example, researchers have not found that any specific diet can lead to or prevent appendicitis.(25)

Complications of Appendicitis

Appendicitis can be a life-threatening condition. If not treated right away, the appendix can burst, spreading an infection throughout the abdomen.

When the appendix bursts, it can produce a pocket of pus called an abscess. A surgeon will need to drain the abscess through a tube placed through the abdominal wall, which is left in place for two weeks while the patient is on antibiotics to clear the infection. Once this happens, an appendectomy can be performed. (6)

Research and Statistics: How Many People Have Appendicitis?

People of any age can get the condition, but appendicitis is most common among teenagers and those in their twenties.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), more than 5 percent of the population will develop appendicitis at some point in their lives. (1)

Related Conditions and Causes of Appendicitis

Other conditions that mimic appendicitis includeCrohn's disease, ulcerative colitis,gallbladder problems,urinary tract infections (UTI), pelvic inflammatory disease,gastritis, intestinal obstruction, abdominal adhesions (bands of fibrous tissue that form between abdominal tissues and organs), and even constipation. (8)

Other conditions that can cause pain in the lower right abdomen area also includeovarian cysts,irritable bowel syndrome(IBS),kidney infection, digestive issues resulting fromlactose intoleranceandfood allergies,hernia, andectopic pregnancy.

Editorial Sources and Fact-Checking

  1. Definition and Facts for Appendicitis.National Institute of Diabetes and Digestive and Kidney Diseases. November 2014.
  2. Kooij IA, Sahami S, Meijer SL, et al. The Immunology of the Vermiform Appendix: A Review of the Literature.Clinical and Experimental Immunology. October 2016.
  3. Bollinger R, Barbas AS, Bush EL, et al. Biofilms in the Large Bowel Suggest an Apparent Function of the Human Vermiform Appendix.Journal of Theoretical Biology. December 2007.
  4. Anderson RE, Olaison G, et al. Appendectomy and Protection Against Ulcerative Colitis.New England Journal of Medicine. March 15, 2001.
  5. Appendicitis.Johns Hopkins Medicine.
  6. Appendicitis: Symptoms and Causes.Mayo Clinic. May 24, 2019.
  7. Gauderer MW, et al. Acute Appendicitis in Children: The Importance of Family History.Journal of Pediatric Surgery. August 2001.
  8. Drescher MJ, et al. Family History Is a Predictor for Appendicitis in Adults in the Emergency Department.Western Journal of Emergency Medicine. December 2012.
  9. Lamps LW. Infectious Causes of Appendicitis.Infectious Disease Clinics of North America.December 2010.
  10. Symptoms and Causes of Appendicitis.National Institute of Diabetes and Digestive and Kidney Diseases. November 2014.
  11. Kaplan G, Tanyingoh D, Dixon E, et al. Ambient Ozone Concentrations and the Risk of Perforated and Nonperforated Appendicitis: A Multicity Case-Crossover Study.Environmental Health Perspectives.August 2013.
  12. Appendicitis: Diagnosis and Treatment.Mayo Clinic. May 24, 2019.
  13. Appendicitis.RadiologyInfo.org. April 21, 2020.
  14. Appendicitis in Children: Overview.Cleveland Clinic. November 17, 2016.
  15. Bundy D, Byerley J, Liles A, et al. Does This Child Have Appendicitis?Journal of the American Medical Association(JAMA). July 2007.
  16. Appendicitis.KidsHealth. July 2018.
  17. Smith MP, Katz DS, Lalani T, et al. ACR Appropriateness Criteria Right Lower Quadrant Pain — Suspected Appendicitis.Ultrasound Quarterly. June 2015.
  18. How to Tell if That Pain Is Your Appendix.Cleveland Clinic. November 12, 2019.
  19. Shah SS, Gaffney RR, Dykes TM, Goldstein JP. Chronic Appendicitis: An Often Forgotten Cause of Recurrent Abdominal Pain.American Journal of Medicine. January 2013.
  20. Peritonitis: Diagnosis and Treatment.Mayo Clinic. June 18, 2020.
  21. Kim D, Butterworth SA, Goldman R. Chronic Appendicitis in Children.Canadian Family Physician. June 2016.
  22. Varadhan K, Neal K, Lobo D. Safety and Efficacy of Antibiotics Compared With Appendectomy for Treatment of Uncomplicated Acute Appendicitis: Meta-Analysis of Randomised Controlled Trials.BMJ.April 2012.
  23. Salminen P, Paajanen H, Rautio T, et al. Antibiotic Therapy vs. Appendectomy for Treatment of Uncomplicated Acute Appendicitis.JAMA.June 16, 2015.
  24. Ho Ting Poon年代,华严李J, Ka NG,等。The Current Management of Acute Uncomplicated Appendicitis: Should There Be a Change in Paradigm? A Systematic Review of the Literatures and Analysis of Treatment Performance.World Journal of Emergency Surgery. October 2017.
  25. Eating, Diet, & Nutrition for Appendicitis.National Institute of Diabetes and Digestive and Kidney Diseases. November 2014.
Show Less
Baidu