Peritonitis natural history

Overview
With treatment, patients usually do well. Without treatment, the outcome is usually poor. However, in some cases, patients do poorly even with prompt and appropriate treatment.

Natural History
If properly treated, typical cases of surgically correctable peritonitis (e.g. perforated peptic ulcer, appendicitis, and diverticulitis) have a mortality rate of about <10% in otherwise healthy patients, which rises to about 40% in the elderly, and/or in those with significant underlying illness, as well as in cases that present late (after 48h). If untreated, generalised peritonitis is almost always fatal.

Complications

 * Sequestration of fluid and electrolytes, as revealed by decreased central venous pressure, may cause electrolyte disturbances, as well as significant hypovolaemia, possibly leading to shock and acute renal failure.
 * A peritoneal abscess may form (e.g. above or below the liver, or in the lesser omentum).
 * Sepsis may develop, so blood cultures should be obtained.


 * The fluid may push on the diaphragm and cause breathing difficulties