When should commence dialysis: focusing on the predialysis condition.

The prevalence of chronic kidney disease (CKD), as defined by the NFK-KDOQI (the national kidney foundation kidney disease outcomes quality initiative) guidelines, is a glomerular filtration rate less than 60 mL/min/1.73 m(2) or the presence of microalbuminuria. CKD is increasing worldwide, leading to an increased risk of cardiovascular disease. There is general agreement on the importance of an early referral to a nephrologist and predialysis educational programs. Establishing the protocol for an early approach may assist in preventing the progression, and the most common complications of renal disease. Predialysis education helps patients in order to choose a renal replacement therapy (hemodialysis, peritoneal dialysis, transplantation) and improve their quality of life. Furthermore, adequate predialysis care allows the nephrologist to promptly prepare for vascular or peritoneal treatment. Regrettably, patients are often referred to the nephrologist when renal failure is already fall in the advanced stage. This is caused primarily by non-nephrologists failing to identify patients at risk for imminent renal failure. Furthermore, they may be defining the patient's degree of renal failure according to the KDOQI classification. To further complicate matters, the serum creatinine alone does not provide an adequate estimate of renal function; however, both the MDRD (the modification of diet in renal disease) equation and the Cockcroft-Gault formula permit the more reliable and accurate estimation of the all-important glomerular filtration rate (GFR). Using the MDRD equation, the KDOQI guidelines recommend referral when GFR is less than 30 mL/min/1.73 m(2). Late nephrology referral is an independent risk factor for early death while on dialysis; it is also associated with a more frequent use of temporary catheters, particularly in the elderly individuals. This subject underlines the importance of a multidisciplinary predialysis approach that may bring additional benefits - beyond referral to a nephrologist - including a reduced hospitalization period and a lower mortality rate. The KDOQI guidelines recommend evaluating the benefits and risks of starting renal replacement therapy when patients reach stage 5 (estimated GFR less than 15 mL/min/1.73 m(2)), although the ideal period for initiation of the replacement therapy remained a source of debate.