Signs and symptoms of peritonitis include:

• Abdominal pain or tenderness
• Bloating or a feeling of fullness (distention) in your abdomen
• Fever
• Nausea and vomiting
• Loss of appetite
• Diarrhea
• Low urine output
• Thirst
• Inability to pass stool or gas
• Fatigue

If you're receiving peritoneal dialysis, peritonitis symptoms may also include:

• Cloudy dialysis fluid
• White flecks, strands or clumps (fibrin) in the dialysis fluid

Infection of the peritoneum can happen for a variety of reasons. In most cases, the cause is a rupture (perforation) within the abdominal wall. Though it's rare, the condition can develop without an abdominal rupture. This type of peritonitis is called spontaneous peritonitis.

Common causes of ruptures that lead to peritonitis include:

• Medical procedures, such as peritoneal dialysis. Peritoneal dialysis uses tubes (catheters) to remove waste products from your blood when your kidneys can no longer adequately do so. An infection may occur during peritoneal dialysis due to unclean surroundings, poor hygiene or contaminated equipment. Peritonitis also may develop as a complication of gastrointestinal surgery, the use of feeding tubes or a procedure to withdraw fluid from your abdomen (paracentesis) and rarely as a complication of colonoscopy or endoscopy.
• A ruptured appendix, stomach ulcer or perforated colon. Any of these conditions can allow bacteria to get into the peritoneum through a hole in your gastrointestinal tract.
• Pancreatitis. Inflammation of your pancreas (pancreatitis) complicated by infection may lead to peritonitis if the bacteria spread outside the pancreas.
• Diverticulitis. Infection of small, bulging pouches in your digestive tract (diverticulitis) may cause peritonitis if one of the pouches ruptures, spilling intestinal waste into your abdominal cavity.
• Trauma. Injury or trauma may cause peritonitis by allowing bacteria or chemicals from other parts of your body to enter the peritoneum.

Peritonitis that develops without an abdominal rupture (spontaneous peritonitis) is usually a complication of liver disease, such as cirrhosis. Advanced cirrhosis causes a large amount of fluid buildup in your abdominal cavity (ascites). That fluid buildup is susceptible to bacterial infection.

Factors that increase your risk of peritonitis include:

• Peritoneal dialysis. Peritonitis is common among people undergoing peritoneal dialysis therapy.
• Other medical conditions. The following medical conditions increase your risk of developing peritonitis: cirrhosis, appendicitis, Crohn's disease, stomach ulcers, diverticulitis and pancreatitis.
• History of peritonitis. Once you've had peritonitis, your risk of developing it again is higher than it is for someone who has never had peritonitis.

Left untreated, peritonitis can extend beyond your peritoneum, where it may cause:

• A bloodstream infection (bacteremia).
• An infection throughout your body (sepsis). Sepsis is a rapidly progressing, life-threatening condition that can cause shock and organ failure.