Peritonitis is an inflammation (irritation) of the peritoneum. This is the thin tissue that lines the inner wall of the abdomen and covers most of the abdominal organs.
Peritonitis is caused by a collection of blood, body fluids, or pus in the belly (abdomen).
One type is called spontaneous bacterial peritonitis (SPP). It occurs in people with ascites. Ascites is the buildup of fluid in the space between the lining of the abdomen and the organs. This problem is found in people with long-term liver damage, certain cancers, and heart failure.
Peritonitis may be a result of other problems. This is known as secondary peritonitis. Problems that may lead to this type of peritonitis include:
- Trauma or wounds to the belly
- Ruptured appendix
- Ruptured diverticula
- Infection after any surgery in the belly
The belly is very painful or tender. The pain may become worse when the belly is touched or when you move.
Your belly may look or feel bloated. This is called abdominal distention.
Other symptoms may include:
- Fever and chills
- Passing little or no stools or gas
- Excessive fatigue
- Passing less urine
- Nausea and vomiting
- Racing heartbeat
- Shortness of breath
Exams and Tests
The health care provider will perform a physical exam. The abdomen is usually tender. It may feel firm or "board-like." People with peritonitis usually curl up or refuse to let anyone touch the area.
Blood tests, x-rays, and CT scans may be done. If there is a lot of fluid in the belly area, the provider may use a needle to remove some and send it for testing.
The cause must be identified and treated right away. Treatment typically involves surgery, antibiotics, or both.
Peritonitis can be life threatening and may cause complications. These depend on the type of peritonitis.
When to Contact a Medical Professional
Go to the emergency room or call 911 or the local emergency number if you have symptoms of peritonitis.
Acute abdomen; Spontaneous bacterial peritonitis; SBP; Cirrhosis - spontaneous peritonitis
Bush LM, Levison ME. Peritonitis and intraperitoneal abscesses. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 74.
Kuemmerle JF. Inflammatory and anatomic diseases of the intestine, peritoneum, mesentery, and omentum. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 133.
Review Date 2/28/2022
Updated by: Debra G. Wechter, MD, FACS, General Surgery Practice Specializing in Breast Cancer, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.