Peritonitis in childhood: aspects of pathogenesis and therapy

The pathogenesis of peritonitis due to hollow-viscus perforation is currently accepted as being mainly based on the local and systemic release of pro- and antiinflammatory mediators triggered by the presence of bacteria and bacterial products in the abdominal cavity. Therefore, treatment consists in focal restoration, intraoperative debridement and lavage, and postoperative measures such as drainage, continuous peritoneal lavage, or scheduled reoperation aiming at the removal of infectious agents from the peritoneal cavity to prevent persisting peritonitis and sepsis. In order to evaluate the pathophysiologic relevance of the bacterial and endotoxin load of the peritoneal exudate, we examined the peritoneal fluid of 20 children with perforated appendicitis for qualitative and quantitative analysis of bacteria, antibiotic concentrations, and endotoxin content. The time period ranged in 12-h intervals from intraoperatively to day 5. Eighteen of 20 fluid specimens (90%) showed endotoxin levels above 1.5 endotoxin units EU/ml (standard <0.1 EU/ml). The most common bacterial species isolated was Escherichia coli, mostly in high concentrations. Despite persisting high endotoxin concentrations and bacterial loads in the peritoneal cavity during the 5 postoperative days, the children recovered uneventfully and the systemic signs of infection disappeared rapidly. In conclusion, neither the bacterial nor the endotoxin load of the peritoneal cavity proved to be associated with the clinical course. Therefore, we hypothesize that during peritonitis compartmentalization of the focus of infection prevents further systemic reactions and ultimately leads to removal of the infectious agents by endogenous mechanisms. At least in peritonitis due to perforated appendicitis in children, adjuvant surgical measures in addition to appendectomy and intraoperative debridement are not necessary.