Inflammation of the peritoneum, the membranous lining of the abdomen

  • More common in males
  • Age, genetics, and lifestyle are not significant factors

Inflammation of the peritoneum, the membrane that surrounds the organs in the abdomen and lines the abdominal cavity, is called peritonitis. The condition is more common in men. It usually occurs as a complication of another abdominal disorder, such as appendicitis. Severe peritonitis may be fatal if not treated rapidly.

What are the causes?

The most common cause of peritonitis is a bacterial infection that has spread from elsewhere in the abdomen. For example, bacteria from the intestine may escape into the abdominal cavity if the intestine is perforated. Possible causes of a perforation include a severe flare-up of a long-term inflammatory disorder, such as ulcerative colitis; intestinal obstruction; a wound such as a stab injury; or surgery.

A less common cause of peritonitis is irritation of the peritoneum. For example, stomach acid may leak into the abdominal cavity and cause irritation if a peptic ulcer perforates the wall of the stomach or the duodenum (the first part of the small intestine). Peritonitis may also develop if bile leaks out from an inflamed gallbladder (see Cholecystitis). Occasionally, the condition is caused by leakage of digestive enzymes into the abdominal cavity as a result of acute pancreatitis.

What are the symptoms?

The symptoms of peritonitis usually develop rapidly. They may include:

  • Severe, constant abdominal pain.

  • Fever.

  • Abdominal swelling.

  • Nausea and vomiting.

In severe cases, dehydration and shock may also occur. Rarely, after an attack of peritonitis, adhesions may develop, in which bands of scar tissue grow between loops of intestine, causing the loops to stick together. Adhesions may cause abdominal pain months after the attack of peritonitis. Another complication may be intestinal obstruction.

If you believe that you may have peritonitis, you should seek medical attention without delay.

What might be done?

It is important that peritonitis is diagnosed and treated as soon as possible. If your doctor suspects that you have peritonitis, he or she will have you admitted to hospital immediately. In hospital, a doctor will examine your abdomen to check for pain or tenderness and you will have X-rays of the abdomen. In addition, you may need a procedure called a laparoscopy, in which the abdominal cavity is examined for abnormalities.

If peritonitis is the result of a bacterial infection, you will be given antibiotics. You may also need intravenous fluids to treat dehydration and shock. Your doctor will treat the underlying cause of the peritonitis. For example, a perforated peptic ulcer will be repaired or a ruptured appendix removed.

If peritonitis is treated immediately, recovery is usually rapid and long-term problems, such as adhesions, are rare.

Treatment: Colectomy

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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