Kids Health Info

Appendicitis 1 - infected appendix

  • Pronounced:
    Appendicitis - uh-pen-deh-sye-tus
    Appendix - uh-pen-diks
    Appendicectomy - uh-pen-da-sect-a-me

    The appendix sits in the bottom right hand side of the large intestine. It is quite small and looks a bit like a little finger. It is on the right side of the abdomen (tummy). The appendix is part of the bowel but it doesn't have a helpful role in the body. If it is removed it is not missed. However, the appendix needs to be removed if it gets infected. 

    An infection of the appendix is called appendicitis. An appendicectomy is an operation (surgery) where the appendix is taken out. See Kids Health Info fact sheet: Appendicitis (2) - appendicectomy.

    Anyone can get appendicitis but it tends to be most common in people aged from 10 - 30 years.

    What happens to the appendix when you get appendicitis?

    When a person gets appendicitis, their appendix will swell. The swelling may be caused by:

    • An infection which may cause the appendix to burst.
    • A small hard piece of faeces (poo) getting stuck in the tube of the appendix (this is called faceolith).

    Either of these will cause the appendix to:

    Appendix- what happens

    Diagnosis of appendicitis needs to be made quickly. A burst appendix will make your child very sick.

    Signs and symptoms

    In children there are many variations of the symptoms, but they can include:

    • Pain that starts around the belly button.
    • Pain that moves to the right side of the abdomen. You may hear this called right iliac fossa pain.
    • Pain can be very bad, and normally is made worse by moving or touching the tummy.
    • High temperature (above 38º C).
    • Nausea (feeling sick) and vomiting.
    • Loss of appetite (don't feel like eating).
    • Diarrhoea/constipation (runny or hard poo).

    What causes the pain?

    Sometimes it can be hard to tell what the cause of the pain is. Younger children might not be able to say what they are feeling. Sometimes the pain can be caused by another medical problem such as gastroenteritis (a tummy bug). Sometimes, if the doctor is not sure what is causing a child's pain, they will keep them in hospital and watch them just in case it is appendicitis. Sometimes, even if they are not sure of the exact problem, doctors decide to perform a small operation to look at the appendix to make sure that appendicitis is not causing the tummy pain.

    How is appendicitis diagnosed?

    • The doctor will ask for your child's history of the symptoms and illness. The doctor will want to know when and where the pain began, and how bad the pain is.
    • The doctor will also give your child a physical examination by checking the site of the pain and feeling the abdomen. This may be done many times and your child may 'guard' - or protect - the area by tensing up the abdominal muscles, because it may be painful.
    • If the doctor is not sure if it is appendicitis, he or she might do an ultrasound or x-ray to take pictures of the abdomen. The doctor may also do a blood test to look for signs of infection.


    If the appendix is infected it is usually necessary to remove it with an operation called an appendicectomy.  Please read the Kids Health Info fact sheet: Appendicitis (2) - appendicectomy for more information.

    Developed in consultation with the RCH Department of Surgery. Many thanks to the parents involved in fact sheet development. First published Mar 2006. Updated September 2012.

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This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital, Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.