What is appendicitis?

Appendicitis is an irritation, inflammation, and infection of the appendix (a narrow, hollow tube that branches off the large intestine). The appendix functions as a part of the immune system during the first few years of life. After this time period, the appendix stops functioning and other organs continue helping fight infection. Although the appendix does not seem to serve any purpose, it can become infected and, if untreated, can burst, causing more infection and even death.

Illustration of the anatomy of the digestive system, adult

What causes appendicitis?

Appendicitis occurs when the interior of the appendix becomes filled with something that causes it to swell, such as mucus, stool, or parasites. The appendix then becomes irritated and inflamed. The blood supply to the appendix is cut off as the swelling and irritation increase. Adequate blood flow is necessary for a body part to remain healthy. When blood flow is reduced, the appendix starts to die. Rupture (or perforation) occurs as holes develop in the walls of the appendix, allowing stool, mucus, and other substances to leak through and get inside the abdomen. An infection inside the abdomen known as peritonitis occurs when the appendix perforates.

Appendicitis may occur after a viral infection in the digestive tract or when the tube connecting the large intestine and appendix is blocked or trapped by stool. Because of the risk of rupture, which may occur as soon as 48 to 72 hours after symptoms begin, appendicitis is considered an emergency and anyone with symptoms needs to see a doctor immediately.

What are the risk factors for appendicitis?

Appendicitis affects 1 in 1,000 people living in the U.S. and is the most common reason for a child to need emergency abdominal surgery.

Most cases of appendicitis occur between the ages of 10 and 30 years. Having a family history of appendicitis may increase a child's risk for the illness, especially in males, and having cystic fibrosis also seems to put a child at higher risk.

What are the symptoms of appendicitis?

The following are the most common symptoms of appendicitis. However, each individual may experience symptoms differently. Symptoms may include:

  • Pain in the abdomen which:

    • May start in the area around the belly button, and move over to the lower right-hand side of the abdomen, but may also start in the lower right-hand side of the abdomen.

    • Usually increases in severity as time passes.

    • May be worse with moving, taking deep breaths, being touched, and coughing or sneezing.

    • May spread throughout the abdomen if the appendix ruptures.

  • Nausea and vomiting

  • Loss of appetite

  • Fever and chills

  • Constipation

  • Diarrhea

  • Inability to pass gas

  • Abdominal swelling

It is important that people with symptoms of appendicitis not take laxatives or enemas to relieve constipation, as these medications and procedures can cause the appendix to burst. In addition, people should also avoid taking pain medication, as this can mask other symptoms the doctor needs to be aware of.

The symptoms of appendicitis may resemble other medical conditions or problems. Always consult your doctor for a diagnosis.

How is appendicitis diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for appendicitis may include the following:

  • Blood tests (to check for signs of infection such as elevated white blood cell count)

  • Urine tests (to rule out a urinary tract infection)

  • Imaging procedures, including the following:

    • Abdominal ultrasound. A diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.

    • Computed tomography scan of the abdomen, with or without barium (also called a CT or CAT scan). A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce horizontal, or axial,images (often called slices)of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.

    • Lower GI (gastrointestinal) series (also called barium enema). A procedure that examines the rectum, the large intestine, and the lower part of the small intestine. A fluid called barium (a metallic, chemical, chalky, liquid used to coat the inside of organs so that they will show up on an X-ray) is given into the rectum as an enema. An X-ray of the abdomen shows strictures (narrowed areas), obstructions (blockages), and other problems.

Treatment for appendicitis

Specific treatment for appendicitis will be determined by your doctor based on:

  • Your age, overall health, and medical history

  • Extent of the condition

  • Your tolerance of specific medicines, procedures, or therapies

  • Expectations for the course of the condition

  • Your opinion or preference

Because of the likelihood of the appendix rupturing and causing a severe, life-threatening infection, doctors will recommend that the appendix be removed with an operation.

Illustration of laparoscopic appendectomy

The appendix may be removed in two ways:

  • Open method. Under anesthesia, an incision is made in the lower right-hand side of the abdomen. The surgeon finds the appendix and removes it. If the appendix has ruptured, a small drainage tube may be placed to allow pus and other fluids that are in the abdomen to drain out. The tube will be removed in a few days, when the surgeon feels the abdominal infection has subsided.

  • Laparoscopic method. This procedure uses several small incisions and a camera called a laparoscope to look inside the abdomen during the operation. Under anesthesia, the instruments the surgeon uses to remove the appendix are placed through several small incisions, and the laparoscope is placed through another incision. This method is not usually performed if the appendix has ruptured.

Generally, without a rupture, recovery after an appendectomy is just a few days. If the appendix has ruptured, recovery is longer and antibiotics are necessary.

People can live a normal life without their appendix. Changes in diet, exercise, or other lifestyle modifications are usually not necessary.