Peritonitis is swelling (inflammation) of the peritoneum -- the tissue that lines the wall of the abdomen and covers the abdominal organs.

Spontaneous peritonitis is usually caused by ascites, a collection of fluid in the peritoneal cavity. This usually occurs from liver or kidney failure.

Risk factors for liver disease include alcoholic cirrhosis and other diseases that lead to cirrhosis, such as viral hepatitis (Hepatitis B or C).

Spontaneous peritonitis also occurs in patients who are on dialysis for kidney failure.

• Abdominal pain and bloating
• Abdominal tenderness
• Fever
• Fluid in the abdomen
• Low urine output

Other symptoms include:

• Chills
• Joint pain
• Nausea and vomiting

Tests that show infection:

• Blood culture
• Cell studies (cytologic examination) of peritoneal fluid
• Chemical examination of peritoneal fluid
• Culture of peritoneal fluid
• Peritoneal fluid analysis (paracentesis)

Other tests:

• Abdominal imaging studies (to rule out other causes of abdominal pain)
• WBC (nuclear) scan

Treatment depends on the cause of the peritonitis.

• Surgery may be needed if peritonitis is caused by a foreign object, such as a catheter used in peritoneal dialysis.
• Antibiotics may control infection in cases of spontaneous peritonitis with liver or kidney disease.
• Intravenous therapy can treat dehydration.

You may need to stay in the hospital so health care providers can rule out other causes of peritonitis, such as appendicitis and diverticulitis.

The infection can usually be treated. However, kidney or liver disease may limit recovery.

• Abscess
• Hepatic encephalopathy
• Hepatorenal syndrome
• Intestinal obstruction from scar tissue
• Sepsis

Call your health care provider if you have symptoms of peritonitis. This can quickly become an emergency situation.

Patients with peritoneal catheters should be treated with sterile techniques. In cases of liver failure, antibiotics may help prevent peritonitis from coming back.

Runyon BA. Ascites and Spontaneous Bacterial Peritonitis. In: Feldman M, Friedman LS, Sleisenger MH, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2006: chap 88.