Magnesium in dialysis patients: serum levels and clinical implications.

Magnesium is the fourth most abundant cation in the body and is involved in many cell functions. Serum magnesium concentration is maintained within a narrow range by the kidney and digestive tract. Patients with chronic renal failure have an increased body magnesium content. In subjects on hemodialysis and peritoneal dialysis the serum magnesium concentration parallels the dialysate magnesium level. Hypermagnesemia in these patients is frequent, usually mild (serum magnesium lower than 1.5 mmol/l) and asymptomatic, but severe and symptomatic hypermagnesemia can be induced by exogenous magnesium administration. The last section of this review briefly summarizes the clinical implications of hypermagnesemia in dialysis population with special interest on the influence of magnesium on bone disease and parathyroid gland function.