[Levels erythrocyte and plasma magnesium in patients in chronic dialysis]

We studied 46 patients on chronic hemodialysis and 6 patients on peritoneal dialysis not taking Mg containing drugs. A colorimetric method was used to measure Mg in plasma and erythrocytes. Corresponding concentrations obtained in 40 healthy volunteers were 0.78 + 0.08 and 2.06 + 0.25 mmol/l. Plasma and erythrocyte Mg concentrations were 1.07 + 0.16 and 2.89 + 0.42 mmol/l in chronic hemodialysis patients and 1.38 + 0.19 and 3.04 + 0.34 mmol/l in peritoneal dialysis patients (p less than 0.0005 against controls). A significant correlation between plasma and erythrocyte Mg concentration was found only in volunteers. A negative correlation between plasma Mg and plasma PTH concentration was obtained in uremic patients. No correlation of plasma PTH and plasma Ca or erythrocyte Mg concentration was found in this group.