Peritonitis prevention in CAPD.

In 12 CAPD patients with frequent peritonitis episodes (1.6 vs 0.5/year in controls), low IgG concentrations in the effluent and reduced opsonic capacity of the dialysate were observed. Intermittent intraperitoneal IgG (dosage: 12 g/3 weeks, duration: 24 months) increased the opsonic capacity for Staphylococcus epidermidis of the effluent 3-fold, while the peritonitis rate fell to 0.2/year. During the treatment interval the effluent IgG levels and opsonic capacity of the dialysate were initially high and fell progressively thereafter. However, even at trough levels it still remained higher than in controls. Interleukin-1 levels increased 2.5-fold from the third to the eighth day. In those patients with lower clinical response, IgG levels and opsonic capacity of the dialysate were only transiently elevated; their macrophages were shown to be deficient in Fc-receptors. Intraperitoneal human recombinant interferon-alpha was able to improve Fc-receptor expression, oxygen metabolite generation of macrophages and bactericidal capacity of the dialysate in these patients. In conclusion, an unusually high peritonitis rate in CAPD patients may be treated by intraperitoneal IgG-application; in poor responders intraperitoneal interferon should be considered.