What Are the Symptoms, Types, Causes, and Treatment Options of Peritonitis?

Medically Reviewed By Darragh O'Carroll, MD
Was this helpful?

Peritonitis refers to inflammation of the peritoneum, usually due to an infection. It is a medical emergency. Call a doctor for any symptoms of peritonitis, such as appetite loss, abdominal discomfort, nausea, or vomiting. The peritoneum is the lining that covers your intestines, liver, kidneys, and other abdominal organs. If this lining becomes inflamed from fluid in the abdomen or an infection, peritonitis can develop. Without treatment, it can spread throughout the body, leading to a life threatening illness called sepsis.

Keep reading to learn more about what peritonitis is, including its symptoms, types, causes, and treatment options.

What is peritonitis?

a nurse is setting up an IV line
PER Images/Stocksy United

Peritonitis involves the inflammation of your peritoneum, which is the lining that covers your abdominal organs. This inflammation is usually from an infection originating in one of the abdominal organs.

Peritonitis is a medical emergency. Seek immediate medical attention if you or someone you are with has any of the symptoms of peritonitis.

Without antibiotics and sometimes surgery, the infection in your abdomen could spread throughout your body and become a life threatening, full body infection called sepsis.

What are the symptoms of peritonitis?

Because the peritoneum covers the abdominal organs, the symptoms are primarily gastrointestinal.

If you notice any of these symptoms, seek medical treatment immediately:

If you receive peritoneal dialysis, you may notice cloudy dialysis fluid due to peritonitis.

You should also seek emergency medical care if you experience any of these symptoms after having had abdominal surgery, a traumatic injury to your abdomen, or peritoneal dialysis, or if you have liver or kidney failure.

Learn what else could cause lower left abdominal pain here.

Is there more than one type of peritonitis?

There are three different types of peritonitis:

  • Spontaneous bacterial peritonitis: This develops as a result of liver or kidney disease or failure. Fluid builds up in the abdominal cavity, called ascites, leading to an infection of unidentifiable origin. This type is also known as primary peritonitis.
  • Secondary peritonitis: This develops as a result of an infection starting elsewhere in the body, such as appendicitis, or due to an abdominal perforation. The primary infection source can be identifiable. Sometimes, surgery — such as appendectomy — is needed to treat the source of the infection.
  • Tertiary peritonitis: This is the least common but most severe type of peritonitis. It is a recurrent infection that occurs in the abdomen less than 48 hours after a controlled event of secondary peritonitis.

Can I have complications from peritonitis?

Sepsis is a serious complication of peritonitis. Without treatment, sepsis can lead to multiple organ failure followed by death. Peritonitis is the second leading cause of sepsis in intensive care units.

Peritonitis is, therefore, a medical emergency. Call a doctor if you or someone you are with develops any symptoms of the condition.

What causes peritonitis?

The most common cause of peritonitis is an infection that begins due to trauma and spreads to your abdominal cavity. In less common scenarios, the inflammation originates in the peritoneum. Peritoneal dialysis is another common way infection occurs.

Possible causes of peritonitis include:

  • abdominal surgery, injury, or trauma, as bacteria can enter the abdomen on anything penetrating the abdominal wall
  • infections, including appendicitis, diverticulitis, pancreatitis, stomach ulcers, and pelvic inflammatory disease, which can spread to the peritoneum
  • liver or kidney failure, which can lead to a buildup of fluid in the abdomen and cause an infection
  • peritoneal dialysis, which is a way to clean your body of impurities if your kidneys no longer function as they should
  • contamination of any part of the dialysis equipment, including the fluid instilled into the abdomen, which can lead to an infection

Learn about bowel perforation here.

What are the risk factors for peritonitis?

Bacteria and other infectious or irritating substances in the abdominal cavity can spread to the abdomen’s lining and lead to peritonitis.  

Some risk factors for peritonitis include:

  • appendicitis
  • an infection in the abdomen
  • liver failure
  • kidney failure
  • Crohn’s disease
  • abdominal organ rupture
  • perforated intestine
  • the use of feeding tubes
  • pancreatitis
  • peritoneal dialysis
  • recent abdominal surgery

What is the outlook for peritonitis?

Early diagnosis is key to the effective management of peritonitis. Call your doctor or go to an emergency room if you notice any symptoms of peritonitis, especially if you have any of the risk factors mentioned above. Early symptom recognition, diagnosis, and treatment can lead to optimal outcomes. 

Without treatment, peritonitis can lead to very serious complications, such as sepsis and death.

How do clinicians diagnose peritonitis?

When you arrive at the hospital with symptoms of peritonitis, a healthcare professional will perform a physical checkup. They will also order certain tests, including blood and urine tests, and scans, such as an X-ray, a CT scan, or an ultrasound scan.

The healthcare professional may also recommend abdominocentesis, which is a procedure that removes fluid from your abdomen to test for infection.

On occasion, exploratory surgery to find the original cause of the inflammation may be necessary. 

How do clinicians treat peritonitis? 

If the healthcare professional determines that you have peritonitis, they will very likely admit you to the hospital. The standard treatments are IV antibiotics and fluids. Some cases of peritonitis also require abdominocentesis.

Abdominocentesis is exploratory surgery to locate the source of the infection or surgery to fix the original problem, such as appendectomy if the infection started in your appendix.

You will also receive medications for sepsis (if appropriate), pain medications, antinausea medications, and any other treatments you need for symptom management.

Learn what to expect during appendectomy here.


Peritonitis describes inflammation of the peritoneum, which is the lining that covers your abdominal organs. Common symptoms include pain, tenderness, nausea, vomiting, and appetite loss. Call a doctor if you have any symptoms of peritonitis, especially if you have recently had abdominal surgery, an abdominal injury, an infection in your abdomen, liver or kidney failure, or peritoneal dialysis.

With quick recognition, assessment, diagnosis, and treatment, you can expect to recover from peritonitis.

Was this helpful?
Medical Reviewer: Darragh O'Carroll, MD
Last Review Date: 2022 May 16
View All Symptoms and Conditions Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.