How to measure residual renal function in patients on maintenance hemodialysis.

Many patients with end-stage renal disease who are on maintenance hemodialysis still have significant residual renal function. Exogenous markers such as inulin and radionuclides, and endogenous markers such as creatinine and urea are commonly used to quantify this residual function. These various methods are described in detail and compared with one another. Residual renal function needs to be considered when the dialysis prescription is written. This contribution of residual renal function to dialysis adequacy and its importance are discussed.