Influence of septic peritonitis on circulating fibronectin, immunoglobulin, and complement: relationship to reticuloendothelial phagocytic function.

This study was designed to quantify the changes in the major serum opsonins--ie, fibronectin, IgG, and C3--during Staphylococcus aureus and Escherichia coli peritonitis as they may functionally relate to RES phagocytic function. Both forms of peritonitis were characterized by acute depletion of fibronectin, IgG, and C3 within 6 h. By 24 h, C3 levels had returned to control levels in both groups. IgG levels remained depressed 24 h following the induction of E coli peritonitis but had normalized by 24 h after Staph aureus challenge. In contrast, fibronectin was markedly elevated by 24 h with both E coli and Staph aureus peritonitis. Hepatic RES phagocytic function was significantly stimulated following induction of either Staph aureus or E coli peritonitis. The rapid increase in fibronectin as well as RES activation during septic peritonitis may represent a generalized host-defense response.