Peritonitis is inflammation of the peritoneum, the thin layer of tissue covering the inside of your abdomen and most of its organs.
The inflammation is usually the result of a fungal or bacterial infection. Infection can be caused by an abdominal injury, an underlying medical condition, or a treatment device, such as a dialysis catheter or feeding tube.
Types of peritonitis include:
- spontaneous bacterial peritonitis (SBP)
- secondary peritonitis
- aseptic (or sterile) peritonitis
SBP is the result of an infection of the fluid in your peritoneal cavity. Secondary peritonitis is usually due to an infection that’s spread from your digestive tract.
Aseptic peritonitis isn’t associated with infection.
Peritonitis is a serious condition that requires immediate medical attention. The infection can spread and become life threatening if it isn’t treated promptly.
Symptoms will vary depending on the underlying cause of your infection. Common symptoms of peritonitis include:
- tenderness in your abdomen
- pain in your abdomen that gets more intense with motion or touch
- abdominal bloating or distention
- nausea and vomiting
- constipation or the inability to pass gas
- minimal urine output
- anorexia, or loss of appetite
- excessive thirst
- fever and chills
The following conditions can lead to peritonitis:
- an abdominal wound, such as a surgical wound
- an abdominal injury
- a ruptured appendix
- a stomach ulcer
- a perforated colon
- liver disease, such as cirrhosis of the liver
- infection of the gallbladder, intestines, or bloodstream
- pelvic inflammatory disease (PID)
- Crohn’s disease
- invasive medical procedures, including treatment for kidney failure, surgery, or the use of a feeding tube
The first step in treating peritonitis is determining its underlying cause.
If you have an intestinal infection, an abdominal abscess, or a ruptured appendix, you may need surgery to remove the infected tissue.
If you’re on kidney dialysis and have peritonitis, you may have to wait until the infection clears up to receive more dialysis. If the infection continues, you might need to switch to a different type of dialysis.
Your treatment must begin promptly to avoid serious and potentially fatal complications.
If you have symptoms of peritonitis, seek medical attention right away. Delaying your treatment could put your life at risk.
A doctor will ask you about your medical history and perform a complete physical exam. This will include touching or pressing on your abdomen, which will probably cause some discomfort.
Several other tests can help a doctor diagnose peritonitis:
- Blood tests. A blood test, called a complete blood count (CBC), can measure your white blood cell (WBC) and red blood cell (RBC) count. A high WBC count usually signals inflammation or infection. A low RBC count may indicate intra-abdominal bleeding. A blood culture can help to identify the bacteria causing the infection or inflammation.
- Imaging tests. Imaging tests, such as CT scans and X-rays, can show any perforations or holes in your peritoneum.
- Fluid analysis. If you have a buildup of fluid in your abdomen, a doctor can use a needle to remove some and send it to a laboratory for fluid analysis. Culturing the fluid can also help them identify bacteria.
If you’re on dialysis, the doctor may diagnose peritonitis based on the appearance of cloudy dialysis fluid.
If it’s not treated promptly, the infection may enter your bloodstream, causing shock and damage to your other organs. This can be fatal.
The potential complications of SBP include:
- hepatic encephalopathy, which is a loss of brain function that occurs when the liver can no longer remove toxic substances from your blood
- hepatorenal syndrome, which is progressive kidney failure in people with advanced liver disease
- sepsis, which is a severe reaction that occurs when the bloodstream becomes overwhelmed by infectious agents
The potential complications of secondary peritonitis include:
In many cases, you may be able to prevent peritonitis by taking steps to prevent the infections or conditions that can lead to it.
If you’re on dialysis:
- wash your hands and fingernails before touching your catheter
- clean the skin around the catheter daily
- follow your doctor’s instructions regarding the care and storage of your medical supplies
If you have severe abdominal pain or an abdominal injury, such as a knife wound, take one of the following actions:
- see a doctor
- go to an emergency room
- call 911 or your local emergency services
You can also consider:
- seeking help for alcohol use disorder, if you’re concerned about your alcohol intake or are at risk for cirrhosis
- using condoms or other barrier methods to avoid contracting the sexually transmitted infections (STIs) that can lead to PID
- limiting your use of nonsteroidal anti-inflammatory drugs (NSAIDs), which are associated with stomach ulcers
- getting prompt treatment if you have symptoms of appendicitis or a diagnosed case of appendicitis
If you have peritonitis, your outlook will depend on the cause of your infection and how far it progressed before treatment began. Medications and surgery are usually able to treat the infection.
If treatment doesn’t begin early, the infection can spread. If other organs are damaged, your recovery will depend on your overall health and how much damage was done.