Peritonitis

What Is Peritonitis? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Cathy Cassata
By Medically Reviewed by 
Reviewed:
Medically Reviewed

Peritonitis is a bacterial or fungal infection of the peritoneum, the thin, silklike membrane that lines your inner abdominal wall.

The peritoneum protects the organs within your abdomen, such as your liver, stomach, and intestines.

Peritonitis results in pain, inflammation, and irritation, and requires immediate medical attention to treat the infection and any underlying condition that may have caused it.

Signs and Symptoms of Peritonitis

Numerous symptoms are linked to peritonitis, including:

  • Abdominal pain or tenderness
  • Bloating or feeling full
  • Fever
  • Nausea and vomiting
  • Loss of appetite
  • Diarrhea
  • Inability to pass stool or gas
  • Low urine output
  • Thirst
  • Fatigue
  • Chills
  • Joint pain
  • Dizziness or weakness

Causes of Peritonitis

Peritonitis often comes from a problem in another part of the abdomen that allows blood, pus, or other body fluids into the abdominal cavity, such as an abscess or perforation in an organ. That’s known as secondary peritonitis. Reasons this might happen include:

Spontaneous bacterial peritonitis happens without an outside cause. It’s usually associated with an abnormal buildup of fluid inside the abdomen called ascites. Some conditions that can cause this include advanced liver disease, kidney disease, certain cancers, and congestive heart failure.

Peritonitis is a potential complication of peritoneal dialysis, a treatment for kidney failure.

Premature babies who have a serious gastrointestinal problem called necrotizing enterocolitis are also susceptible.

How Is Peritonitis Diagnosed?

Your doctor will most likely start with a physical exam of your abdomen to feel if it is unusually tender or firm.

They may also conduct one or more of these tests:

Blood tests can reveal if you have a high white blood cell count, and a blood culture can determine if there are bacteria in your blood.

Imaging tests, such as an X-ray, ultrasound, or computerized tomography (CT) scan, can check for fluid, gas, masses, or abscesses in your abdomen or other perforations in your gastrointestinal tract.

Peritoneal fluid analysis is done by using a thin needle to take a sample of the fluid in your peritoneum. An elevated white blood cell count in the fluid may indicate an infection or inflammation, and a culture of the fluid may also indicate if bacteria are present.

Treatment and Medication Options for Peritonitis

Once the cause of peritonitis is identified, treatment usually begins immediately, although in cases related to diverticulitis, watchful waiting may be considered. If left untreated, peritonitis can lead to severe, life-threatening conditions.

Treatment may include antibiotics to help fight the infection and keep it from spreading.

Emergency surgery may be necessary to remove infected tissue, treat the underlying cause of the infection, and prevent the infection from spreading.

Other treatments, such as pain medications, intravenous (IV) fluids, supplemental oxygen, and a blood transfusion may be used if you are hospitalized for peritonitis.

Prevention of Peritonitis

Your doctor may prescribe antibiotics as a preventive measure if you have a history of peritonitis or have peritoneal fluid buildup as a result of a medical condition like liver cirrhosis.

When peritonitis is associated with peritoneal dialysis, it is often caused by germs around the catheter that is used to remove waste from the body. If you’re receiving peritoneal dialysis, there are steps you can take to prevent peritonitis. These include:

  • Frequent hand washing, especially before touching the catheter
  • Cleansing skin around the catheter daily with an antiseptic
  • Wearing a surgical mask when dialysis fluids are exchanged
  • Storing supplies in a sanitary area

Complications of Peritonitis

If left untreated, peritonitis can cause the following complications:

  • Dehydration
  • Bacteremia, or a bacterial infection of the bloodstream
  • Sepsis, a fast-moving and life-threatening condition in which the body’s response to an infection is out of balance, leading to inflammation over a large part of the body
  • Hepatic encephalopathy, which is the loss of brain function caused by the liver’s inability to remove toxins from the blood
  • Hepatorenal syndrome, which occurs when there’s progressive kidney failure in people with cirrhosis of the liver

  • Organ failure and death

Research and Statistics: How Many People Have Peritonitis?

Little research exists examining the total number of peritonitis cases that occur each year.

Still, a 2014 paper suggested that the rate of peritonitis associated with peritoneal dialysis has declined over the past few decades. According to the researchers, incidence of peritonitis in this patient population in the United States in the 1980s and early 1990s averaged 1.1 to 1.3 episodes per year of treatment. After the year 2000, many centers have reported 0.2 to 0.6 episodes per year of treatment.

The researchers say the improvement in rates can be attributed to advances in technology in peritoneal dialysis, as well as standardization of antibiotic therapy.

Related Conditions of Peritonitis

Certain conditions increase the risk of peritonitis, including necrotizing enterocolitis and being on peritoneal dialysis for kidney failure.

Necrotizing enterocolitis is a serious intestinal disease in premature babies in which the lining of the intestinal wall becomes infected and inflamed. This can ultimately lead to the death of the tissue in the intestine. These babies may show the following signs and symptoms, which usually develop in the first two weeks after birth:

  • Bloating or swelling in the abdomen
  • Not feeding well
  • Frequent vomiting that might be greenish
  • Bloody stool, constipation, or diarrhea
  • A redness or abnormal color to the abdomen
  • Lack of energy
  • Fever
  • Low or unstable body temperature, slowed heart rate, or low blood pressure
  • Pauses in breathing (apnea)
Treatment for the disease includes discontinuing feedings, removing air and fluid from the stomach and intestines, and administering intravenous fluids and antibiotics. In more severe cases, surgery may be needed to remove dead bowel tissue.

Peritoneal dialysis is a treatment for kidney failure, a condition in which the kidneys lose the ability to function properly and cannot remove waste and balance fluids in the body. During peritoneal dialysis, a cleansing fluid flows through a catheter placed in the belly and the lining of the abdomen — called the peritoneum — and acts as a filter to remove waste from the blood. These treatments can be done at home, at work, and even while traveling.

If you develop peritonitis related to peritoneal dialysis, you may notice the following symptoms:

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

While you’re being treated, you may need to receive dialysis in another way until your body heals from the infection.

If peritonitis persists or recurs, you may need to permanently switch to a different form of dialysis.

Resources We Love

Favorite Organizations for Information on Peritonitis

National Kidney Foundation (NKF)

NFK is a nonprofit organization dedicated to scientific research and innovation, as well as educating the public and advocating for all people with kidney disease. Get essential facts about peritonitis and find ways to get involved by volunteering or joining events to raise awareness and fundraise to fight kidney disease.

Mayo Clinic

The Mayo Clinic provides everything you need to know about causes, symptoms, treatment, and prevention of peritonitis.

Favorite Online Support Group

Renal Support Network (RSN)

RSN offers monthly virtual support group meetings via Zoom at no charge to people living with kidney disease and their families. Topics include diet, exercise, hobbies, and more. The organization also offers annual patient education meetings free of charge.

Favorite Resource for Becoming an Advocate

Dialysis Patient Citizens (DPC)

This nationwide, nonprofit organization is led by patients and provides a number of resources for dialysis and predialysis patients and their families. With DPC’s help you can volunteer to become a patient ambassador and represent the organization in your local community. DCP provides monthly newsletters, as well as multiple teleconference calls per year, with instructions for ways you can take action. This can range from writing a letter to inviting a local member of Congress to your facility.

Additional reporting by Ashley Welch.

Editorial Sources and Fact-Checking

Show Less