peritonitis

Peritonitis 

Definition

Peritonitis is an inflammation of the membrane which lines the inside of the abdomen and all of the internal organs. This membrane is called the peritoneum.

Description

Peritonitis may be primary (meaning that it occurs spontaneously, and not as the result of some other medical problem) or secondary (meaning that it results from some other condition). It is most often due to infection by bacteria, but may also be due to some kind of a chemical irritant (such as spillage of acid from the stomach, bile from the gall bladder and biliary tract, or enzymes from the pancreas during the illness called pancreatitis). Peritonitis has even been seen in patients who develop a reaction to the cornstarch used to powder gloves worn during surgery. Peritonitis with no evidence of bacteria, chemical irritant, or foreign body has occurred in such diseases as systemic lupus erythematosus, porphyria, and familial Mediterranean fever. When the peritoneum is contaminated by blood, the blood can both irritate the peritoneum and serve as a source of bacteria to cause an infection. Blood may leak into the abdomen due to a burst tubal pregnancy, an injury, or bleeding after surgery.

Causes and symptoms

Primary peritonitis usually occurs in people who have an accumulation of fluid in their abdomens (ascites). Ascites is a common complication of severe cirrhosis of the liver (a disease in which the liver grows increasingly scarred and dysfunctional). The fluid that accumulates creates a good environment for the growth of bacteria.

Secondary peritonitis most commonly occurs when some other medical condition causes bacteria to spill into the abdominal cavity. Bacteria are normal residents of a healthy intestine, but they should have no way to escape and enter the abdomen, where they could cause an infection. Bacteria can infect the peritoneum due to conditions in which a hole (perforation) develops in the stomach (due to an ulcer eating its way through the stomach wall) or intestine (due to a large number of causes, including a ruptured appendix or a ruptured diverticulum). Bacteria can infect the peritoneum due to a severe case of pelvic inflammatory disease (a massive infection of the female organs, including the uterus and fallopian tubes). Bacteria can also escape into the abdominal cavity due to an injury that causes the intestine to burst, or an injury to an internal organ which bleeds into the abdominal cavity.

Symptoms of peritonitis include fever and abdominal pain. An acutely ill patient usually tries to lie very still, because any amount of movement causes excruciating pain. Often, the patient lies with the knees bent, to decrease strain on the tender peritoneum. There is often nausea and vomiting. The usual sounds made by the active intestine and heard during examination with a stethoscope will be absent, because the intestine usually stops functioning. The abdomen may be rigid and boardlike. Accumulations of fluid will be notable in primary peritonitis due to ascites. Other signs and symptoms of the underlying cause of secondary peritonitis may be present.

Diagnosis

A diagnosis of peritonitis is usually based on symptoms. Discovering the underlying reason for the peritonitis, however, may require some work. A blood sample will be drawn in order to determine the white blood cell count. Because white blood cells are produced by the body in an effort to combat foreign invaders, the white blood cell count will be elevated in the case of an infection. A long, thin needle can be used to take a sample of fluid from the abdomen in an effort to diagnose primary peritonitis. The types of immune cells present are usually characteristic in this form of peritonitis. X-ray films may be taken if there is some suspicion that a perforation exists. In the case of a perforation, air will have escaped into the abdomen and will be visible on the picture. When a cause for peritonitis cannot be found, an open exploratory operation on the abdomen (laparotomy) is considered to be a crucial diagnostic procedure, and at the same time provides the opportunity to begin treatment.

Treatment

Treatment depends on the source of the peritonitis, but an emergency laparotomy is usually performed. Any perforated or damaged organ is usually repaired at this time. If a clear diagnosis of pelvic inflammatory disease or pancreatitis can be made, however, surgery is not usually performed. Peritonitis from any cause is treated with antibiotics given through a needle in the vein, along with fluids to prevent dehydration.

Prognosis

Prognosis for untreated peritonitis is poor, usually resulting in death. With treatment, the prognosis is variable, dependent on the underlying cause.

Prevention

There is no way to prevent peritonitis, since the diseases it accompanies are usually not under the voluntary control of an individual. However, prompt treatment can prevent complications.

Resources

Books

Isselbacher, Kurt J., and Alan Epstein. "Diverticular, Vascular,and Other Disorders of the Intestine and Peritoneum." In Harrison's Principles of Internal Medicine, edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1997.

Key terms

Ascites — An accumulation of fluid within the abdominal cavity.

Cirrhosis — A progressive liver disease in which the liver grows increasingly more scarred. The presence of scar tissue then interferes with liver function.

Diverticulum — An outpouching of the intestine.

Laparotomy — An open operation on the abdomen.

Pancreatitis — An inflammation of the pancreas.

Perforation — A hole.

Peritoneum — The membrane that lines the inside of the abdominal cavity, and all of the internal organs.

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peritonitis /peri·to·ni·tis/ (-to-ni´tis) inflammation of the peritoneum, which may be due to chemical irritation or bacterial invasion.

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per·i·to·ni·tis (pr-tn-ts)

n.

Inflammation of the peritoneum.

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peritonitis

[per′itənī′tis]

Etymology: Gk, peri + teinein, to stretch, itis

an inflammation of the peritoneum. It is produced by bacteria or irritating substances introduced into the abdominal cavity by a penetrating wound or perforation of an organ in the GI tract or the reproductive tract. Peritonitis is caused most commonly by rupture of the appendix but also occurs after perforations of intestinal diverticula, peptic ulcers, gangrenous gallbladders, gangrenous obstructions of the small bowel, or incarcerated hernias, as well as ruptures of the spleen, liver, ovarian cyst, or fallopian tube, especially in ectopic pregnancy. In some cases, peritonitis is secondary to the release of pancreatic enzymes, bile, or digestive juices of the upper GI tract, and there are reports of postoperative peritonitis caused by cornstarch used to powder surgical gloves. The bacteria most frequently identified as causative agents in peritonitis are Escherichia coli, Bacteroides, Fusobacterium, and anaerobic and aerobic streptococci. Pneumococci occasionally found in peritonitis in girls are thought to enter the abdominal cavity via the vagina and fallopian tubes. See also acute diffuse peritonitis, adhesive peritonitis.

observations Characteristic signs and symptoms include abdominal distension, rigidity and pain, rebound tenderness, decreased or absent bowel sounds, nausea, vomiting, and tachycardia. The patient has chills and fever; breathes rapidly and shallowly; is anxious, dehydrated, and unable to defecate; and may vomit fecal material. Leukocytosis, an electrolyte imbalance, and hypovolemia are usually present, and shock and heart failure may ensue.

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peritonitis (per´itnī´tis),

n an inflammation of the peritoneum produced by bacteria or irritating substances introduced into the abdominal cavity by a penetrating wound or perforation of an organ in the gastrointestinal (GI) tract or the reproductive tract. Peritonitis is caused most commonly by rupture of the vermiform appendix.

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peritonitis

inflammation of the peritoneum. The cause may be infectious or chemical. Typical signs are rigidity and pain on palpation of the abdominal wall, absence of feces, severe toxemia and fever. In horses there is a mild colic and in dogs and cats there is often effusion. Paracentesis may show evidence of inflammation.

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acute diffuse peritonitis

in the early stages pain is evident all over the abdomen. There is soon a disappearance of pain, a profound toxemia develops and the disease may go undetected.

acute local peritonitis

added to the usual signs there is a sharp pain response over the site of the lesion.

adhesive peritonitis

peritonitis characterized by adhesions between adjacent serous structures.

aseptic peritonitis

see chemical peritonitis (below).

biliary peritonitis, bile peritonitis

that due to the presence of bile in the peritoneum; choleperitoneum. Is detected by the color of the fluid withdrawn by paracentesis. See also bile peritonitis.

chemical peritonitis

may be caused by leakage of bile, urine, gastric juices or pancreatic enzymes in acute pancreatitis. Infusion of irritant materials can cause a similar chemical irritation.

chronic peritonitis

is manifested by chronic toxemia, bouts of colic due to adhesions and an accumulation of exudate which may cause a visible distention of the abdomen. See also retroperitoneal abscess.

chylous peritonitis

an uncommon result of abdominal trauma or tumors, intestinal obstruction or lymphangiectasia.

egg peritonitis

peritonitis in birds due to release of an egg into the peritoneal cavity with subsequent infection by Escherichia coli which have ascended via the oviduct.

feline infectious peritonitis (FIP)

see feline infectious peritonitis.

idiopathic peritonitis

one caused by a primary infection of the peritoneal cavity, e.g. feline infectious peritonitis, or hematogenous spread from a noncontiguous site.

post-stripping peritonitis

fatal peritonitis occurring in cultured salmonid fish soon after stripping, sometimes before. Caused by a number of gram-positive cocci and coccobacilli; Carnobacterium piscicola considered to be the most important infection.

primary peritonitis

see idiopathic peritonitis (above).

septic peritonitis

secondary to disruption of the abdominal cavity or a hollow viscus, particularly leakage from the gastrointestinal tract.

silent peritonitis

asymptomatic peritonitis.

starch granulomatous peritonitis

talcum powder, and to a lesser extent, other powders used on surgical gloves can cause a granulomatous reaction on the peritoneum.

traumatic peritonitis

perforation of the gut wall or abdominal wall introducing infection into the peritoneal cavity. May result from stake or bite wound, inexpert passing of urinary or insemination catheter, sadistically by a broom handle in the vagina, or stabbing of the rumen as an emergency measure in acute ruminal tympany. See also traumatic reticuloperitonitis.

urine peritonitis

prolonged exposure of the peritoneum to urine, usually due to leakage from the bladder or a ureter, results in a peritonitis and the development of uremia. Bacterial infection may also be introduced.

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peritonitis

Inflammation of the peritoneum, often due to infection–especially bacteria, but also post-traumatic, injury and bleeding, or disease–eg, SLE. See Bile peritonitis, Dialysis-associated peritonitis, Idiopathic sclerosing peritonitis, Sclerosing metanephric peritonitis, Spontaneous bacterial peritonitis, Vernix caseosa peritonitis.