What is peritonitis?

Peritonitis refers to the inflammation of the abdominal lining (known as the peritoneum), which covers the inner surface of abdominal wall and organs such as the stomach, liver and intestines.

Peritonitis is classified based on the cause and extent of this inflammation. The two types include:1

  • Primary (spontaneous) peritonitis – occurring primarily due to a bacterial infection, without other causes within the abdomen
  • Secondary peritonitis – develops when an organ within the abdomen becomes infected, which spreads throughout the peritoneum

Causes of secondary peritonitis include diseases within the digestive system and pelvis or trauma to the abdominal organs (e.g. perforated viscus, inflammatory bowel disease, appendicitis, pancreatitis or gynaecologic infection) and surgery.1

Signs and symptoms of peritonitis

Symptoms of peritonitis can vary according to the cause of inflammation. However, they commonly include:1,2

  • Severe pain within the abdomen
  • Fever
  • Constipation
  • Nausea and vomiting
  • Inability to pass gas


Peritonitis is a severe condition that can be fatal. It’s important that medical attention is sought immediately, with hospitalisation likely. Diagnosis may involve examination by a surgical specialist and a variety of tests and scans.

  • Blood tests – which checks white blood cell count and culture to guide the use of antibiotics
  • Imaging tests – an x-ray may be undertaken to check for perforations in the gastrointestinal tract, while an ultrasound or CT scan can help determine the cause of the peritonitis
  • Peritoneal fluid analysis – analyses peritoneal fluid to reveal presence of bacteria or infection


Treatment for peritonitis will depend on the type and the severity of the inflammation. The most common treatment is surgery to remove infected tissue, repair the organ or abdominal area affected, along with antibiotics to treat the infection.1,2 

Other treatments may include pain killers, intravenous fluids, blood transfusions or abscess (pus-filled collection of fluid) drainage with a needle, depending on your signs and symptoms.


For a full list of references, please click here.
  1. healthdirect. (2018). Peritonitis. Retrieved on 20 November 2019 from
  2. National Kidney Foundation. (2019). Peritonitis. Retrieved on 20 November 2019 from

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