Biocompatibility of a 1.1% amino acid-containing peritoneal dialysis fluid compared to a 2.27% glucose-based peritoneal dialysis fluid.

The biocompatibility of a 1.1% amino acid-containing peritoneal dialysis fluid (AA-PDF) was compared to that of a 2.27% glucose-based peritoneal dialysis fluid (G-PDF). Peritoneal macrophages (PMO), isolated from the peritoneal dialysis (PD) effluents of 10 chronic ambulatory PD patients, were tested for their phagocytosis capacity and peak chemiluminescence response. A subset of PMO was cultured for 24 h with and without lipopolysaccharide (LPS) to study the release of interleukin-1 beta (IL-1 beta) and 8 (IL-8). As control, the interleukin release by blood monocytes of healthy donors was tested. The opsonic activity of the PD effluent was tested as well. Compared to PMO isolated from G-PDF, PMO from AA-PDF showed a significantly better phagocytosis capacity. There was no difference in the peak chemiluminescence response between PMO from AA-PDF and G-PDF. The release of IL-1 beta by unstimulated PMO isolated from the two fluids did not differ. Compared to control monocytes, however, PMO from both fluids showed a considerable spontaneous release of IL-1 beta. When stimulated with LPS, IL-1 beta production by PMO from G-PDF exceeded that of PMO from AA-PDF (p < 0.002). The release of IL-8 by PMO from G-PDF was significantly higher in comparison with PMO from AA-PDF, both spontaneously and after stimulation with LPS (p < 0.02). The opsonic activity of undiluted and to 75% diluted effluents was significantly higher for G-PDF than for AA-PDF (p < 0.01). Thus, compared to the regularly used G-PDF, the phagocytosis capacity as measure for PMO function seems to be better preserved after in vivo exposure to AA-PDF. In addition, the higher release of IL-1 beta and IL-8 by PMO isolated from G-PDF suggests a stronger intra-abdominal activation of PMO, with G-PDF acting as a chemical inflammatory agent. Whether the lower opsonic activity of the AA-PDF is more important for biocompatibility than the other parameters is not clear. Therefore, it is concluded that, although macrophage function is better preserved, it is not proven that the 1.1% AA-PDF studied has an improved biocompatibility compared to 2.27% G-PDF.