Influence of pH-neutral peritoneal dialysis solution

We evaluated the influence of a neutral peritoneal dialysis solution (PDS) on the peritoneum. The subjects were 10 stable PD patients using conventional PDS. We substituted pH-neutral PDS (PD Solita A: Shimizu Medical, Tokyo, Japan) for conventional PDS (Gambrosol A: Shimizu Medical). Effluent from 4-hour dwells was collected, and the appearance rate of cancer antigen 125 (CA125-AR) was calculated using the method of Pannekeet et al and corrected to body surface area. The dialysate-to-plasma creatinine (D/P Cr) was obtained, and personal dialysis capacity (PDC) was evaluated at 3-month intervals. Mean daily ultrafiltration volumes did not significantly change when pH-neutral PDS was used. The mean CA125-AR obtained 1 month after substitution was twice as high as that before substitution (139.2 +/- 47.3 U/min/1.73 m2 before substitution vs. 286 +/- 126.2 U/min/1.73 m2 1 month later). However, mean values of CA125-AR were maintained at higher levels and did not significantly vary for 7 months after PD fluid substitution. When the change in CA125-AR (delta CA125-AR) was calculated as the ratio of the CA125-AR value before substitution to that after substitution at the respective measurement points, delta CA125-AR negatively correlated with D/P Cr. However, none of % area, % absorption, or % plasma loss significantly correlated with the delta CA125-AR obtained 6 months later. Although mesothelial cell viability may increase with the use of pH-neutral PDS, the level of the increase may differ depending on the severity of peritoneal damage. In addition, the use of a neutral PD fluid did not improve the endothelial cell system. In the future, development of a novel osmotic pressure-regulating substance substituting for glucose is essential to the development of PD fluids with higher biocompatibility.