Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at March 15, 2016

Peritonitis is an infection involving the abdominal cavity. This infection has many potential causes and symptoms that are treatable with proper medical care.


Definition & Facts

Peritonitis refers to a range of infections that often cause inflammation of the peritoneum. The peritoneum is a thin lining of tissue that surrounds and protects most of the abdominal organs. Because of this, there are a number of types of peritonitis.

The disease has the potential to be chronic or acute, as well as generalized or localized. Most types are identified by a large accumulation of cells, pus, and blood in the body cavity. Some peritonitis infections are caused by bacterial infections or fungal infections and some are caused by complications of other medical conditions.

All types of peritonitis are characterized by abdominal pain and should be dealt with by a medical professional as soon as possible in order to fight infection. If peritonitis is left diagnosed or untreated, the infection of the abdomen can lead to a potentially fatal full body infection.

Symptoms & Complaints

Peritonitis has a wide range of symptoms and signs. This list ranges from mild to extremely painful. Mild symptoms that often go unnoticed are low levels of energy and a low urine output. Because these are potential symptoms of many diseases they are not the best markers of peritonitis.

The most common and extreme symptom is pain localized to the abdominal area. This pain can range from slight tenderness at the touch to extreme discomfort. Often times abdominal pain, slight or severe, is made worse by movement. Because the abdominal area is large, pain may be centered in a small area, but it can extend throughout the abdomen over time.

A patient with peritonitis will often also complain of bloating or abdominal distension. Diarrhea or constipation and inability to pass gas are expected. With this disease, loss of appetite has been seen in patients and is usually followed by nausea and vomiting.

A fever may also occur. With the many symptoms of peritonitis, muscle spasms are possible. These spasms will cause the muscles to contract and feel rigid or hard to the touch. Some patients show only one or two symptoms and others show many, so it is important to seek medical attention at the first signs of discomfort.


The most common cause of peritonitis is a rupture in an organ covered by the lining. The list of organs includes the stomach, small intestine, large intestine, spleen, liver, pancreas and adrenal glands. Perforations, or tears, of these organs can occur from physical trauma.

When a tear in an organ occurs, bodily fluids leak into the body cavity. This accumulation of fluid contains bacteria which is then held in the body cavity by the peritoneum. The peritoneum reacts to this bacteria by trying to fight it, resulting in inflammation and peritonitis.

Peritonitis can also occur with other medical problems. Peritonitis can result as a complication from an appendicitis, diverticulitis, or pelvic inflammatory disease. If peritonitis is not identified and goes untreated, it can cause an infection of the bloodstream or sepsis. Sepsis is a full body response to infection and is life-threatening.

Diagnosis & Tests

A medical professional may diagnose peritonitis after a physical examination and medical history. Palpation, or touching, of the abdomen to determine a patient’s level of pain is common. A medical professional may also check for rigidity or bloating of the abdomen while examining a patient. Sometimes a cough test is administered. A physician may ask a patient to force a cough in order to assess the level of pain after coughing.

There are a number of medical tests that can confirm a diagnosis after a physical examination. Usually, this includes a blood test to check for infection. This test would allow a physician to see a patient’s white blood cell count. A high level of white blood cells is the body’s reaction to an infection.

A blood culture could also be used to determine if bacteria is present in the blood stream. Abdominal X-rays, ultrasound or CT scan, can be used to check for perforation in the gastrointestinal tract.

For patients who receive peritoneal dialysis, a peritoneal fluid analysis is common. This procedure requires a physician to take a sample of fluid from the peritoneum with a needle. The fluid is then tested to determine a white blood cell count. A culture may also be performed to assess the level of bacteria in the fluid.

Treatment & Therapy

Hospitalization is possible with peritonitis. If the infection is mild, patients are often given a round of antibiotics to help fight the infection. These antibiotics are helpful too in preventing an infection from spreading to other parts of the body. The length of a round of antibiotics will vary depending on the level of infection and cause of a patient’s peritonitis.

If antibiotics prove to be ineffective, surgery becomes necessary. A surgical team may remove infected tissue or repair a perforation that may be causing the infection. This is most common in patients who suffer from appendicitis, or a ruptured stomach. As with most hospital stays the use of intravenous fluids, pain medications and supplemental oxygen are standard.

Prevention & Prophylaxis

Because peritonitis results more commonly from abdominal trauma, it is important to receive medical attention soon after injury. If abdominal pain becomes strong enough that sitting or moving is difficult, or other symptoms like nausea, bloating, or fever occur, call 911.

For patients who have pancreatitis, diverticulitis or liver disease, it is important to be watchful and aware of the potential for infection in order to treat peritonitis quickly and effectively.