Cytotoxicity of Continuous Ambulatory Peritoneal Dialysis (CAPD) Solutions. A Biocompatibility Study Involving Human Polymorphonuclear Granulocytes Rather than Laboratory Animals

Continuous amulatory peritoneal dialysis (CAPD) is a well-established treatment for renal failure. Peritonitis is the most important and serious complication to CAPD. The predisposition of patients to contract peritonitis has been attributed to functional impairment of immunoactive cells in the peritoneal cavity due to cytotoxicity of the dialysis solutions used.

A model for biocompatibility studies of CAPD solutions is presented, in which the migration and phagocytotic capacity of normal isolated human polymorphonuclear granulocytes (PMN) were examined after exposure to the test solutions. The methods proved to be highly reproducible.

The commercially-available lactate-based CAPD solutions tested reduced PMN function, mostly due to their low pH. Cell function was improved by elevation of pH, but not to the control level, when the cells were exposed to RPMI — a standard cell culture medium. A new bicarbonate-based CAPD solution proved to be less cytotoxic than the lactate-based ones, and is at present undergoing clinical evaluation.