Peritoneal dialysis adequacy: not just small-solute clearance.

Two indices of small-solute clearance, Kt/V urea and creatinine clearance, are widely used as markers of peritoneal dialysis (PD) adequacy. It has become clear, however, that increasing the small-solute clearance above a minimum level does not result in improved long-term PD outcomes. Several other factors may affect optimal dialysis outcome. These include, but are not limited to, ultrafiltration, inflammation, malnutrition, and mineral metabolism. In the present article, we briefly review data regarding the relationships between the foregoing factors and survival on PD.