Defective Opsonic Activity of Peritoneal Effluent during Continuous Ambulatory Peritoneal Dialysis (CAPD): Importance and Prevention

To evaluate peritoneal immunological defenses and to find a way to prevent peritonitis we have studied the capacity of peritoneal dialysis effluent (PDE) to opsonize bacteria, and the phagocytic activity of peritoneal macrophages (PM). The subjects were 40 uremic patients followed for a mean period of 36 months and 40 normal women who underwent laparoscopy (controls).

Opsonic capacity for Staphylococcus epidermidis of undiluted PDE from CAPD patients with low peritonitis incidence (LPI) proved to be similar to that of 10% control serum. However, the capacity of effluent from patients with a high peritonitis incidence (HPI) was noticeably inferior. In these cases, IgG concentration in PDE was lower than in LPI patients.

There was a significant correlation between opsonization capacity for bacteria and IgG concentration values in PDE. We found inverse correlations between opsonic capacity of PDE and number of episodes of peritonitis.

Phagocytic capacity of PM from CAPD patients was similar to that of control PM when micro-organisms were preopsonized by control serum.

Treatment with intraperitoneal intmunoglobulin raised PDE opsonization capacity and lowered the incidence in those with previous HPI, thus demonstrating the importance of abnormal opsonization in CAPD peritonitis and the possibility of preventing infection by prophylaxis with intraperitoneal immunoglobulin. Intravenous immunoglobulin does not reduce the incidence of infection.