The appendix is a long finger-like tube connected to the first part of the large intestine (the colon). When the appendix becomes inflamed and infected, this is called appendicitis. When appendicitis occurs, the appendix can swell and may burst, which can cause infection in the abdomen.
- In the U.S., more than 5% of the population will develop appendicitis at some point in their lives, and it is the most common cause of acute abdominal pain requiring surgery. It most commonly occurs in teenagers and young adults in their twenties but it can occur at any age.
- If the appendix has not burst, it may be possible to treat appendicitis with antibiotics, but without surgery there is a chance appendicitis will return so surgery is usually recommended.
- If the appendix has burst, surgery is usually more complicated and cuts might be larger or the surgery might take longer.
- Some studies have shown that the appendix may act as a storehouse for “good” digestive bacteria, and it may play a role in helping restore the balance of this good bacteria in the gut after a severe case of diarrhea, such as with cholera or dysentery.
- The risk of infection from appendicitis is much more significant than the need to maintain a reserve of good gut bacteria, and removing the appendix does not cause any long-term problems.
Complications of an appendectomy are rare but may include:
- Infection
- Bleeding
- Scarring
- Abscess
- Hernia
- Allergic reaction to anesthesia
What Are Symptoms of Appendicitis?
Symptoms of appendicitis include:
- Severe pain in the lower abdomen, on the right side
- Pain is usually the first symptom
- The pain often starts near the belly button and moves toward the lower right side
- Pain occurs rapidly and gets worse in a matter of hours
- Pain is worse when you take deep breaths, cough, sneeze, or move
- Is often severe
- Loss of appetite
- Nausea and vomiting
- Fever
- Stomach upset
- Increased gas (flatulence) or an inability to pass gas
- Irregular bowel movements
- Abdominal bloating
- Diarrhea
- Feeling ill (malaise)
- Constipation
Call a doctor right away or get to a hospital’s emergency department if you have symptoms of appendicitis. The risk of the appendix bursting increases after the first 24 hours of symptoms, and if the appendix bursts, surgery to treat it is more complicated.
What Causes Appendicitis?
Causes of appendicitis may include:
- Blockage of the lining of the appendix
- Infection in the gastrointestinal (GI) tract or elsewhere in your body that results in swollen tissue in the wall of the appendix
- Inflammatory bowel disease (IBD)
- Stool, parasites, stones or growths that can block the appendiceal lumen
- Abdominal trauma
How Is Appendicitis Diagnosed?
Appendicitis can sometimes be diagnosed with a physical exam. The doctor will press on the abdomen to check for tenderness in the lower right part side and swelling or rigidity.
Tests to confirm appendicitis or rule out other conditions may include:
- Computerized tomography (CT) scan
- Abdominal ultrasound
- Magnetic resonance imaging (MRI)
- X-ray of the abdomen
- Blood tests
- Urine tests to rule out kidney stones or urinary tract infection (UTI)
- Chest X-ray or CT scan to rule out pneumonia
- In women:
- Pregnancy test
- Pelvic exam to rule out ovarian cysts or pelvic inflammatory disease
- Transvaginal ultrasound
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https://www.uptodate.com/contents/appendicitis-in-adults-the-basics?search=Appendicitis&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
https://www.niddk.nih.gov/health-information/digestive-diseases/appendicitis
https://www.nhs.uk/conditions/appendicitis/treatment/
https://wonderopolis.org/wonder/what-does-your-appendix-do