What is peritonitis?

Causes and Symptoms

Peritonitis is an acute condition that typically results from a bacterial infection
of the membrane lining the abdominal organs or the abdominal cavity itself, known as the peritoneum. Primary bacterial peritonitis occurs because of a generalized infection, usually with Streptococcus pneumoniae with peritoneal seeding and is usually seen in adolescent girls. Secondary bacterial peritonitis, on the other hand, is caused by the rupture and perforation of a hollow organ of the gut, such as the appendix or a gastric ulcer. Other causes of peritonitis include postsurgical complications, catheter contamination in dialysis patients, and infection with enteric bacteria from the gut that cause pelvic inflammatory disease (PID) in women. A type called spontaneous bacterial peritonitis is a complication of ascites seen in chronic liver or kidney failure.

The clinical presentation of peritonitis may vary depending on the severity and source of infection and may range from no symptoms to severe abdominal pain, fever and chills, diarrhea, inability to pass feces and urine, shock, worsening of renal failure, or encephalopathy. Typical bacterial peritonitis may be manifested by an extremely still patient who finds that even slight movement aggravates the pain. Physical examination may reveal tenderness over the abdomen with positive rebound tenderness, fluid in the abdominal cavity, and other signs of liver or kidney failure.

For diagnosis, needle aspiration (paracentesis) of the fluid from the abdominal cavity can be done for biochemical and microbiological analyses, including cell count, gram stain, and culture; ultrasound guidance may help in locating the abdominal fluid. Blood cultures may be helpful in some cases. If rupture of a hollow organ is the cause, an x-ray of the abdomen shows the presence of air under the diaphragm. Blood cultures are useful in diagnosing spontaneous bacterial peritonitis and primary peritonitis. Ultrasound examination is used to detect fluid in the abdomen.

Treatment and Therapy

The treatment of peritonitis depends on its presentation and cause. Supportive measures to secure adequate respiration and circulation are used for patients who are in critical condition. A ruptured internal organ is usually treated surgically after the patient is stabilized. Infection is managed with antibiotics. Inadequate or improper management of peritonitis may lead to abscess formation, intestinal obstruction, hepatorenal syndrome, encephalopathy, sepsis, and ultimately death.

Peritonitis is an emergency situation, and it is of utmost importance that the condition be diagnosed and treated at an early stage in order to avoid fatal complications. Any case of significant abdominal pain must be examined thoroughly and investigated to rule out peritonitis. The prognosis depends directly on the promptness of treatment.

Bibliography

Augustin, Rolf. Peritonitis in CAPD. New York: Karger, 1987.

Badash, Michelle. "Peritonitis." Health Library, October 31, 2012.

Conn, Harold O., Juan Rodés, and Miguel Navasa. Spontaneous Bacterial Peritonitis: The Disease, Pathogenesis, and Treatment. New York: Marcel Dekker, 2000.

Fry, Donald E., ed. Peritonitis. Mount Kisco, N.Y.: Futura, 1993.

Fry, Donald E. Surgical Infections. London: JP Medical Ltd., 2013.

Icon Health. Peritonitis: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References. San Diego, Calif.: Author, 2004.

Kasper, Dennis L., et al., eds. Harrison’s Principles of Internal Medicine. 16th ed. New York: McGraw-Hill, 2005.

"Peritonitis." Mayo Clinic, July 9, 2011.