If appendicitis is not treated, the appendix can burst and cause potentially life-threatening infections.

Call 999 for an ambulance if you have abdominal (tummy) pain that suddenly gets much worse and spreads across your abdomen. These are signs that your appendix may have burst.

Peritonitis

If your appendix bursts, it releases bacteria into other parts of the body. This can cause a condition called peritonitis if the infection spreads to the peritoneum (the thin layer of tissue that lines the inside of the abdomen).

Symptoms of peritonitis can include:

• severe continuous abdominal pain
• feeling sick
• being sick
• a high temperature (fever)
• a rapid heartbeat
• shortness of breath with rapid breathing
• swelling of the abdomen

If peritonitis is not treated immediately it can cause long-term problems and may even be fatal. Treatment for peritonitis usually involves antibiotics and the surgical removal of the appendix (appendectomy).

Read more about treating peritonitis.

Abscesses

Sometimes an abscess forms around a burst appendix. This is a painful collection of pus that occurs as a result of the body’s attempt to fight the infection. It can also occur as a complication of surgery to remove the appendix in about 1 in 500 cases.

Abscesses can sometimes be treated using antibiotics, but in the vast majority of cases the pus will need to be drained from the abscess. This can be carried out under ultrasound or computerised tomography (CT) guidance using local anaesthetic and a needle inserted through the skin followed by placement of a drain.

If an abscess is found during surgery, the area is carefully washed out and a course antibiotics is given.

Read more about treating abscesses.