Serial peritoneal macrophage function studies in CAPD patients with peritonitis.

Abstract

Continuous ambulatory peritoneal dialysis, peritoneal macrophage, IL-1, IFN-r, TNF, phagocytosis. Peritoneal macrophages (PM) perform first-line defense activity against peritonitis, the most important complication in CAPD therapy. Our longitudinal study compared the PM function in 14 patients in a low peritonitis occurrence group (LPOG) and 6 in a high peritonitis occurrence group (HPOG) before and during peritonitis; all started CAPD therapy after January 1988. The results show that at the onset of peritonitis, PM function including bactericidal killing (BA) activity, phagocytosis index (PI), H2O2 release, interleukin-1 (IL-1) and tumor necrosis factor (TNF) secretion can increase rapidly in the LPOG. However, this was absent in the HPOG. Both groups had a decrease of PM immunological function in the initial 7 to 10 days after onset of peritonitis, then PM functions began to return toward their pre-peritonitis state. However, in the HPOG, the recovery of PM function was very slow, resulting in significantly lower PM functions. In vitro, when normal PM were put into peritonitis dialysate, IL-1, TNF production and PI, BA activity of PM were decreased. This suppressor activity was absent in the peritonitis-free dialysate. These results suggest a suppressor factor(s) in the HPOG peritoneal dialysate may decrease the function of PM rather than cause easy peritonitis development.