Peritonitis is inflammation (the body's way of reacting to injury and/or infection) of the peritoneum. The peritoneum is the tissue that lines the abdomen and covers the internal organs.


  • Conditions or injuries cause organs to leak stool, bacteria, fungi or chemicals (such as bile or other digestive juices) into the abdomen. When these substances come into contact with the peritoneum, they may cause irritation or infection.

  • Many conditions can cause peritonitis, including:

  • Pancreatitis.

  • Diverticulitis.

  • Appendicitis.

  • Ulcers.

  • Crohn's disease or ulcerative colitis.

  • Other infections inside the abdomen or pelvis.

  • Abdominal injury.

  • Injury to the stomach or esophagus (food pipe).

  • Cancer.

  • Liver disease.

  • Peritoneal dialysis (a procedure used to cleanse the blood when the kidneys are unable to do so).

  • Tuberculosis.


Symptoms of peritonitis may include:

  • Severe pain.

  • Abdominal swelling.

  • Fever and chills.

  • Nausea and vomiting.

  • Poor or no appetite.

  • Inability to pass gas or stool.


Diagnosis begins with a complete physical exam. The abdomen may be tender or hard and board-like. Testing may include:

  • Blood tests.

  • Urinalysis

  • Stool analysis (if there is associated diarrhea).

  • Paracentesis: a procedure where a very thin needle may be used to take a sample of fluid from within the abdomen. This fluid can be examined for signs of infection.

  • X-ray.

  • Ultrasound.

  • CT scans.


This must be treated quickly, to avoid a severe, life-threatening infection that involves the whole body (sepsis). This must be done in the hospital.

Treatment for peritonitis may include:

  • Antibiotics.

  • Surgery to remove infected fluid and tissue.

  • Surgery to treat conditions that cause peritonitis (such as an appendectomy for appendicitis).


Even after successful treatment in the hospital, treatment and recovery will continue at home. It is important to:

  • Take medicines (such as antibiotics) exactly as prescribed by your caregiver.

  • If you were taking prescription medicines for other problems before you developed peritonitis, ask about when you should re-start these medicines.

  • Only take over-the-counter or prescription medicines for pain, discomfort or fever as directed by your caregiver.

  • Follow your prescribed diet. You might need a higher fiber diet to help avoid constipation.

  • Drink extra water.

  • Use a stool softener or laxative, if recommended.

  • Get extra rest.


  • You have increased abdominal pain or tenderness, or abdominal swelling.

  • You develop an unexplained oral temperature above 102° F (38.9° C).

  • You start to have the chills.

  • You have new problems with passing urine.

  • You develop chest pains and/or shortness of breath.

  • You experience nausea, vomiting or diarrhea.

  • You are unable to pass gas or stool.

  • You have had surgery and notice the healing incision has become hot, red, swollen or is leaking pus or blood.